Home

Packaged Water Chiller with Screw Compressors

Contents

1. 3 31 EE 5s NA 0 T EE ____ 1 31 E A8 Jone 3 31 318 NA 0 T NA8 cw eL 3s 0 A8 E E E 95s 0 T 000001 ER ER 3 31 gt bae NA 0 T 13 5 ___ A8 m De 1 31 LLL 28 LL 56 IM 549 M enu 28 Service test 1 REEGELE ___ 9 E 5 1102 S E89 10 9 Output 7 Off 10 Output 8 Off 11 Output 9 Off 12 Output 10 0 13 Output 11 0 14 Output 12 0 15 Output 13 0 16 Output 14 0 17 Ou
2. PVM1 IM 549 61 Control Cabinet Layout ALS 300A 380A 62 Keypad High voltage wireway DB2 m 1 EXVB2 Mech relays F1CB F2 AOX DIOX NB Low voltage wireway High voltage wireway gt E 8 MCB280 ADI 8 E e 5 5 8 gt c m Low voltage wireway D TB4 TB5 Low voltage wireway Low voltage wireway N m 4 HUN 141 5 12 LJ LI colo 178 amp T7 PE BE 3 84 8 T6 2 14 ER FB FB 12 13 14 31 32 33 34 35 FB FB FB FB FB 6 7 8 10 11 111112 1113 15 23 25 211 22 14 24 T DL1 DL2 CB2 M1 M2 DL3 CB3 IM 549 Wiring legend 0704352C 01 Standard Standard ALARM BELL BACK OR SIDE OF CTRL BOX PSI PS3 PUMPDOWN SWITCHES CTRL BOX SWITCH PA
3. Xr 81 ma 5 2 808 vy 08 OE WO4 4110490 901491 80 24 NOLI NOS sin 5 0 803 NOIL23NNOS AIOS WID 1000 325 021 AV 14510 Gvaaan W300N 3NOHg 08908 BAIA ND ISNVdX3 2150812373 AYM3OVH M Sue 1004 2074 1 310N 1 M L zs Sf Ce S 009 5 JS 0712 L ss s ooi 99 111 099 qs 005 4431 4 039 405 T W3OnOSNYMI 755384 1 205 2 dida UIONISNVUL 755384 206 0 um 1005 14 299 T 755384 OC 20 6 0 18 1995 Ze m 55384 205 0 TER 0 EI NOS 84 339 et sm 08908 104100 062 08 8 7041409 510481 791120 A Noua 015 dPI31 alen M35N30NO2 0N02 15 44013 538 01 Soe LINN 1N32H3d 901vNY IS Le DUD 4831 NOIL2nS CUS Ce 290 AMAL 011205 SindNti PIS Le 347 ONO 615 Z 2ul2 ont INI 0902 341 3479205 1041405 jen FIS M3NUOJSNY
4. 38 puro Day 9 20 0 dur 0days 2 ipse wA 0 T ai Dur 0days Wzoxe NAo T 25 fis Date WAO NA8 Cane 25 ___ M enu 22 Service test 1 Output T 1 Output 1 0 2 EXV 1 3 EXV Pos 2 xxx 4 Output 4 0 5 Output 5 0 6 Output 6 0 7 Output 7 0 8 Output 8 0 9 Output 9 0 0 760 0 760 0 0 0 2 a aan WE UNE 5 __ _ 2 2 2 2 42 10 Output 1020 11 Output 1120 12 Output 12 0 13 Output 13 0 14 Output 14 0 15 Output 15 0 16 Output 16 0 17 Output 1720 18 Output 18 0 19 Output 19 0 20 DH1 00000000 21 DH2 00000000 22 5 x xx Vdc ojojo 21212 ojo 0 0 0 0 0 Digital Input 0 Open Digital Input 0 1 Closed 1 Closed Actual vdc Value IM 549 M enu 23a Alarm 5 valuesfor R 22 refrigerant D isplay Factory Set Point StpPumpDn xxpsi kPa 34 234 2 54 13 372 FullPumpDownz No No No yes FreezStat xxpsi kPa 54 372 FreezH20 xx x F C 36 0 2 3 Hi Press xx
5. E 88 06000250 RetumSpt xx F C OatMaxRst oct Note the minus sign is not displayed with three digit numbers indicates Centigrade values M enu 20b Lvg evap spts valuesfor 134a refrigerant ERR REES PY Not Changeable 3 CntiBand x x F C 4 StartUpD T x x F C 0030 0 016 peu S5 EE 6 ResetO pt None 7 4 40 Ma Network Ice 8 Not Changeable ENSE DENEN Not Changeable 150 83 RetumSpt F 540 123 750 032 OatMaxRst 60 0 155 500 1155 30 0 11 Note the minus sign is not displayed with three digit numbers indicates Centigrade values M enu 21 Soft load spts D isplay Factory Set Point i 0 SoftLdM axStg x LoadDelay 2 Softtoad xx min IER d 54 IM 549 M enu 22 Compressor at D isplay Factory Set Point Lead Auto 1 gt 2 gt 3 gt 4 1 gt 3 gt 2 gt 4 2 gt 1 gt 4 gt 3 2 gt 4 gt 1 gt 3 Auto 3 gt 4 gt 1 gt 2 3 gt 1 gt 4 gt 2 4 gt 3 gt 2 gt 1 4 gt 2 gt 3 gt 1 CHE Pain PS M enu 23a H ead presspt valuesfor R 22 refrigerant Range 1 foa 6 60 2 Mini 096 ox 3 149 66 100140 90965 5 0
6. 35 Level 1 Controller 35 Level 2 Controller 35 Keypad Key Functions 36 Keypad PaSSWOMd 36 Category ter o 36 Menu Le KEE 37 Item Group EE 37 Action GTOUD ssec te 37 Example of Keypad Operation sees 37 Personal omputer Specification 37 MicroT ech M enu Structure 38 Status Menge nee te Rr REESE 38 Control Mengs occ rh ern Ee en 38 Alarm 5 etre ra LR nas 38 Schematics And D 60 Control Cabinet Layout 60 Wiring Eegend xti 63 PES Unit Control niente 64 5 8 5 OUTPUT reni 65 PFS MiCrOTech ite eed ete genres 66 AES pe I Pede 67 ALS 8 Stage Output 68 5 n i ceca co t ees 69 ALS Field Wiring ioni enel 70 3 Introduction This manual provides installation setup and troubleshooting information forthe M icroTech controller provided on McQuay screw compressorchillers Please referto installation manual IM 548 for unit application information as well as w
7. 5 NA8 LI LLL 9 Bate NAO 9 H E 2 iz Date NAO a ur Odays 5 E 48 IM 549 M enu 25 Service test o o o d 00 5 LIE _ Output o 10 0 0 N e ef e 2 N elo win On 0 Digital Input 0 Open 1 Closed Digital Input 0 Open 1 Closed 331 DH3 00000000 Digital Input 0 Open 1 Closed 33 Vd M enu 26a Alarm 5 values for R 22 refrigerant 1 SisPumpDn kPa 2 FwPumpbown No Ps RE ERR 99 469 E1753 380062 280 426 9322938 Note indicates Centigrade values On O M enu 26b Alarm spts
8. WART D Keng STANDARD UNT gek INCOMING FELD POWER 24V OR 120V 6071 270 TT 510 549 ALS 8 Stage O utput 0716996D 01 LINE 120VAC460 1 FROM UNIT CTRL SCHEM SVOC REG FROM _ MCB250 AUX OUT SEE MCROTECH SCHEM 400 OUTPUT LINE 401 43 p E 8250 873 SEE MCROTECH 402 5 M SCHEMATIC Get 107 881 35 40 SEE UNT CTRL SCHEMATIC Lacs CHILLED WATER PUMP RELAY 4 y OPEN USED FOR EXV CONTROL m SEE MICROTECH SCHEMATIC AUX OUT as HOT GAS BYPASS HGRI L 7 185 7 e 134 9 4 COMPR 1 SOL FEED We 175 185 7 52 kr E en Tee COMPR 9 BOT RIGHT SOL FEED 24 ser UNIT CTRL 173 SCHEMATIC Ht 26 77 COMPRESSOR 1 Fu 76 uw COMPR 1 BOT LEFT SOL LVENT eR UNT 33 34 HOT GAS BYPASS CONTROL 0 e 231 273 SEE UNT CTRL 21 70 7 1 278 SCHEMATIC COMPR 2 CONTACTORS SCHEMATIC 2222 35 277 24 COMPR 2 SOL FEED 295 37 275 28 COMPR 2 BOT RICHT SOL FEED COMPRESSOR 72 276 2056 C
9. WII LN 27 IVA 021 uh e eze i I OT RES e 22 A ue Wach z 13 43 z wu SE 34 18 2541 vze E L 2WO NOSMJS 39252544 a H 5 E wa nu E 9 H 7666905 YOSNIS TIAIT WO mad oe A 9 oce KIT ege eg 553 EECH D ERE irae E 598 ue gl k 8 Ko D MS FER 2005 BRE EN 168 18 912 H co Av ldSIQ 0628on IMS 4015 MONM OL 310N gt ap QvdA33 Wilms 4015 310938 wiv 795 m An L MOIS AO WAT ese e SUA 558 AYM ONU SAY E e ENOJ 00 Seti 13LON v f 06 32 9 9 9 999 j at ETE lt 19 f onm 6 9 av S 069 ug wl 49 mg 034 34 FER cza IM 549 ALS Field Wiring 0719740C 01 Disconnect Unit main by others terminal block GND lug 3phase 2 00 SE EES To compressor s power WE and fan motors supply 9 4 1 ee cue Fused control circuit trans
10. Liquid Ln xxx x F C N A SubC oolg xxx x F C C N A F Dscharge2oo x F Open F Short F C 39 M enu 8 Circ 2 temp s Satur Evap xxx F C N A C SuctLine xxx x F Open F Super Ht xxx x F C F Satur Cond xxx F C N A C Liquid Ln xxx x F C N A F SubCoolgz xxx x F C N A F Dscharge xxx x F Open F Short F C M enu 9 Chiller amps Screen Display 1 Percent LA axx M enu 13 Control mode M enu 10 Comp run hours Screen Pt 3 4 50 000K S s 1 75 6 2 25 ___8 2050 2 75 M enu 11 Compr sarts CL M enu 12 Air temp Screen Display 1 OutDoor xxx x F C D isplay Factory Set Point Manual Unit Off Automatic Manual Staging Service Testing Manual Unit Off 3 EEE 181 M enu 14a Lvg evap spts valuesfor R 22 refrigerant Actv Spt xxx x F C D isplay Factory Set Point __ Evap xxx x F C CntriBand x x F C 44 6 7 10 80 12 2 26 7 3 0 1 1 0 5 0 0 5 2 7 StartUpD T x x F C 3 0 1 1 0 5 0 0 5 2 7 ShutDn D T2 x x F 1 5 0 0 0 3 0 0 0 1 6 M
11. botes 13 o tee dr tape 15 Analog O iie ote 16 Digital QUtpUts 17 Installation 18 Controller C altbration 18 Field Wiring Ee 18 Analog Sensors and Transducers 18 Digital Input Signals 18 Digital 18 Interlock Wiring 18 External Alarm Circuit 18 Power Wiring testo e memi 18 Power Supplies ENEE 18 Demand Limit and Chilled Water Reset Signals 18 Communication 18 Modem oe iet 19 Telephone Line for Remote Modem Access 19 U nit Sequence of peration 19 Off Conditions cca nna penat 19 Start Up xiu tee xe di Gace 19 Waiting for tete ee Des pid 19 Start Requested 19 e ette rm 19 Opened EXV 20 Low AmbientStart e ee ip e dence 20 Cool Stage 0 through Bi 20 Compressor Control 20 Normal Compressor Staging Logic 20 Project Ahead Calculation 21 Interstage Timer 21 Anti Cycle Timer ai iet e een d n 21 Compressor Heater Control 21 Lead Lag Of Refrigerant 22 Automatic Lead Lag ER Manual Lead Lag
12. 4 8 3 BLK 5232 RC port A direct PC connection Q 5 GND GND 52 Connection to RMS 4 Bar 3 BLK 85485 c remote monitoring sequence ommunication orto NMP 1 4 CLR RS485 port network master panel Q ex 2 Ox 5 GND GND Condenser flow switch MOM by others te y Gs Time Off clock Remote stop 77777 Heen E car If remote stop control by others is used remove jumper E een from terminals 60 to 61 Manual 61 flow switch Ka n by others __________ 63 4 7 Alarm bell TB5 by others p Qe GND 1 102 Output relay 0 203 X _ 24 VAC E 5 4 e 107 27 35 VA max 71 McQuay 13600 Industrial Park Boulevard P O Box 1551 Minneapolis MN 55440 USA 612 553 5330
13. 50 549 M enu 32 2 prev alarm Screen 2 3 Ps 3curmAam 8 9 5cuemAam 0 o M enus for Four 4 Screw C ompressors U nits M enu 1 Chiller tatus OFF Manual Mode System Sw Remote Comm Remote Sw Time Clock Alarm PumpDnSw s Starting WaitForLoad CoolStageDn CoolStageUp CoolStaging Manual Cool InterStg xxx sec Hold Stage min Hi Loop Temp OFF SystemSw ManualMde Alarm PumpDwnSw CycleTime xx WaitFlooded lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx IM 549 M enu 33 3 prev alarm Screen 1 icwemMam Cid xii 3 1 4 5 3curmAam 9 5cuemAam M enu 3 Circ 2 satus OFF SystemSw ManualM de Alarm PumpDwnSw CycleTime xx WaitFlooded lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx M enu 4 Circ 3 satus OFF SystemSw ManualM de Alarm PumpDwnSw CycleTime xx WaitFlooded waitF lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx 51 M enu 5 Circ 44 satus
14. nona 30 Display Format a 30 MicroT ech Component T est Procedures amp ALS Units 30 Status LED Diagnostics 30 Red LED Remains see 30 Red and Green LEDS 30 Troubleshooting Power 30 Troubleshooting Communications Problems 31 Troubleshooting the Keypad Display Interface 31 Display is Hard to 31 Back Light Not Eit cete e 31 Display Is Blank or Garbled 31 Troubleshooting Analog Inputs 32 Analog Input Not Read by the MCB 32 Troubleshooting Digital Inputs 32 Digital Input Not Read by the MCB 32 Troubleshooting Analog Outputs 32 Analog Output Device Is Not Operating Correctly 32 Troubleshooting Output 5 33 One LED 33 AN EDS OUt rii eU e de 33 LED Lit Output Not Energized 33 Output Energized LED Not Lit eee 33 Contact Chatter 33 IM 549 Troubleshooting Solid State Relays 34 MCB Replacement s eee 34 Connecting The Communications Trunk 35 Communications Cable
15. 5 POWER TO COMPR SOL RELAYS X 875 SEE STAGING SCHEM LIME 5415 1 1 REOS to A ss 8 MI AUX 2 be 181 182 13 RELAY en 20 155 aa RUM St 2695 157 Wei RECAY 15 1 47 e F RECAY 47 55 58 SS COMPRESSOR See NO 1 57 po e MHP 2 0 5 23 0 160 mekom 02 eham SCHEM FOR EZ COMPLETE een 186 UST For Tas KEE 2073 KEE TE UNT 81 515 876 8 92 830 LL WWE 5 CONHECHED XU GA TO 17 FOR EXPANSION VALVE BOARD 306 SEE MCROTECH SCHEM LNE 45332 S gt Tv x HIR 2 4 240 a ais 2 SCH 244 25 _ el ae 255 242 AUX 2 be 201 iss 3871 233 3 33 254 ies 183 bs 171 2 P RELAY 387 COMPRESSOR 2 RIT 9 1 E 264 265 a MHPR2 225 8 lt 25 ug Ke deeg die a o EIN M 33 RELAY 8 1 34 P us S200 er 254 246 2 MOTE m ie End REDUCED INRUSH OR WHEN OLEI I OM THE UNT 250 249 WRE 5 COMMECTED 2 0 4 106 2 e 15 NOTE muove wer
16. 60 1 549 Control Cabinet Layout ALS 205A 280A C31 SC31 OB2 SC41 High voltage wireway TB6 Ss Mech relays 5 EXVB1 EXVB2 3 8 5 Mech relays F1CB F2 5 AOX04 DIOX18 6 Low voltage wireway High voltage wireway E N 8 5 E MCB 280 ADI z E o z z v OBI o 8 gt m Low voltage wireway 2 D TB4 TB5 Low voltage wireway Low voltage wireway 60 N ai 8 T2 a a 1 50 50 1181 amp 17 ae BE 83 4 8 T6 2 T FB FB FB FB 12 13 14 15 16 17 5 1 31 41 32 42 33 35 43 GRD IER FB FB 6 7 9 10 11 34 44 5 11 112 13 15 23 25 M M 10 21112 14 24 2 OL1 0L3 012 OL4 CB1 CB3 CB2 CB4 C1 M1 M3 M2 C2 M4
17. OFF SystemSw Alarm PumpDwnSw CycleTime xx WaitFlooded waitF lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx Lvg Evapz xxx x F C Short F C Open F C Ent Evap xxx x F C Short F C Open F C Ent Cond xxx x F C Short F C Open F C Lvg Condz xxx x F C Short F C Open F C M enu 7 Circ 1 press Evap xxx x psi kPa xx F C Evap 145 psi kPa Open N A F Short N A F Cond xxx x psi kP a Cond 450 psi kPa Open N A F C M enu 8 Circ 42 press Evap xxx x xx F C Evap 145 psi kPa F C Open N A F C Short N A F Cond xxx x psi kP a Cond 450 psi Open N A F Short F 52 M enu 9 Circ 43 press Evap xxx x psi kPa xx F C Evap 145 psi kPa F Open N A F C Short N A F Cond 450 psi kPa Open N A F Short N A F C E 0 0 5 Position io Cond FanStage x M enu 10 Circ 4 press Evapz xxx x psi kPa xx F C Evap 145 psi kPa Open N A F C Short N A F C Cond xxx x psi kP a Cond 450 psi kPa Open N A F C Sh
18. iere 22 2 Electronic Expansion Valve 22 au EET 22 Exv Superheat Control 22 Forced EXV Position Change 22 EXV Evaporator Pressure 23 Chilled Water Reset ptions 23 Chilled Water Reset Remote 4 20MA 23 Ice lee 23 Network RESE uie ave eid ep egi es 23 Return Water Reset 1 24 Remote Demand 24 Network Demand Limit 0 24 Soft ect cp ete m deni 24 Max Pull ele EE 24 Condenser Fan Control eene 24 Condenser Fan Staging 24 Head Pressure Control 24 Lift Pressure Calculation 25 Lift Pressure Dead 25 Condenser Fan Stage Up 26 High Pressure Stage Up 26 Condenser Fan Stage 26 SpeedTrol eti ne ec e eae 26 Pumpdown 26 Automatic Pumpdown 26 Manual mee 27 Service Pumpdown 27 Safety Systems AA 27 System Alarms ee Berti de roe decet ius 27 0550 tre mites 27 Bad Phase Voltage AA 27 SD anie tes 27 Chi
19. Enter Enter Enter Personal C omputer Specification McQuay Monitor Software 1 IBM PC or 100 true compatible 486DX or better including a 3 1 44 MB floppy diskette drive utilized for loading the MicroTech Monitor program into the hard disk of the computer Also provides capability of archiving historical data and system back up b 8MegabyteRAM Random Access M emory The com puter must have 8 Megabytes in order to run the MicroTech Monitor Program c AsynchronousSerial C ommunicationsAdapter A direct communications interface connection between the PC and the MicroTech Controller The communications port must be recognized as or COM2 and the connector should be a 9 Pin Male d Super VGA Graphics Adapter For high resolution graphics and data display e Parallel Printer Port Forhard copy custom reports of all accumulated data IM 549 A INCR When changing the value of a menu item entry pressing INCR shifts the menu item display line to the next higher value or next available selection B DECR When changing the value of a menu item entry pressing DECR shifts the menu item display line to the next lower value or previous available selection C ENTER Once a change has been made to a desired value pressing ENTER locks in the new value D CLEAR Pressing ALARMS followed by CLEAR clears the current alarm Also when a change is made to a me
20. The refrigerant circuit will be shut down if liquid injection is lost during normal chiller operation One automatic re start will occurafterthe cycle timer expires If another no liquid run fault is recorded after the re start the circuit will be shut down and the alarm output will be energized Can t start low evaporator pressure Ifthe evaporator pressure is less than 4 psi when a compres sor start is requested the start will be aborted Low evaporator pressure A low evaporator pressure alarm will occur if the refrigerant pressure drops below the low pressure cutout set point default 2 psi Freeze protect stage down and freeze stat protect The controller records the amount of time the evaporator refrigerant pressure is below the freeze stat set point de fault 54 psi The magnitude of the error will determine the time delay before a circuit stage down or alarm shutdown occurs Table12 Emo 5 0 AlamDelay 100 seconds 87 seconds 74 seconds 60 seconds 48 seconds 35 seconds 22 seconds 0 seconds 28 Once the time delay is satisfied the controller will stage down once every 20 seconds If the controller stages down to cooling stage 0 the circuit will pump down and the compressor will stop The circuit will restart automatically when the anti cycle timer expires Failed pre purge The start sequence will be aborted if the compressor cannot pre purge the evaporator Faile
21. pare 21119 2 2 2 2 IM 549 Group Chiller Part Number 5714335Y Date August 1996 Packaged Water C hiller with Screw C ompressors Models ALS125A thru 204A ALS205A thru 280A ALS300A thru 380A PFS150A thru 200A McQuav 1996 McQuay International Air Conditioning Table of C ontents Introduction 4 General D escription 4 Control Panel Features 5 Software Identification 5 Controller Layout 2 22 6 Component Data 6 Microprocessor Control 6 Analog Digital Input Board ADI Board 7 rp ades 7 Electronic Expansion Valve Board EXV 7 Analog Output Board AOX 8 8 Sensors And T ransducers 9 Standard Sensors seo det 9 Optional Sensor Packages 9 Thermistor Sensors 9 Pressure Transducers 00 11 Liquid Presence 8 6 11 Sensor Locations 12 Analog INPUTS
22. s 50 S000 5875 9 1 910096 8 0 25 00000 9 420500 Cl RTE 5659 4 8759 M enu 16 Control mode M enu 14 Compr sarts D isplay 1 E 3 ERR M enu 15 Air temp Screen Display D isplay Factory Set Point Manual Unit Off Automatic Manual Staging Manual Unit Off Service Testing M enu 17a Lvg evap spts valuesfor R 22 refrigerant D isplay Factory Set Point Actv Spt xxx x F Not Changeable 2 Lg Evap xxx x F C 44 6 7 10 80 12 2 26 7 ___ 38 6 Return 4 40 Ma Network Ice 8 ig SE 7 xx xma 1 ReturnS pt F 1 12 13 4 MaxChWRst xx x F C 10 0 5 5 54 0 12 3 No OaTRst xx x 75 0 23 9 1 0 5 0 0 5 2 7 1 0 5 0 0 5 2 7 0 0 3 0 0 0 1 6 0 1 1 0 0 0 0 5 Not Changeable 0 0 45 0 0 0 25 0 eu 0 90 322 PC RRE 90 900 1781 3227 F CC 0 900 66 32 2 CF C 32 2 17 HiChWTmp xxx x 60 0 15 5 20 0 90 0 6 6 32 2 Amb Lock 00 990 178 322 Note the minus sign is not displayed with
23. 1 1 0119 9 Fax alarm T8 9 5 T7 option 2 8 os uj T Microprocessor Control Board M CB1 The Model 250 Microprocessor Control Board contains the electronic hardware and software required to monitor and control the unit It receives input from the ADI Board and sends commands to the Output Board to maintain the unit s optimum operating mode for the current conditions Status lights are mounted on the control board to indicate the operating condition of the microprocessor Figure2 MCB1 ee 549 Analog D igital Input Board Board The ADI Board provides low voltage power for the tempera ture and pressure sensors It also provides electrical isola tion between the Microprocessor Control Board and all 24V switch inputs LEDs are furnished on the board to give a Figure3 ADI RECH 221 SPAN BRA O utput B oard The Output Board contains up to 24 solid state relays which are used to control all compressors condenser fans sole noid valves and alarm annunciation Figure 4 Output board HRRRE 29 8 i H H Electronic Expansion Valve Board EXV Board Each EXV Board will directly control up to two electronic expansion valves The boards may be cascaded together for Figure5 EXV board RN2 40 GRH RED YEL Ee AARE visual indication of the status of all digital inputs All analog and digital
24. 659 9 959 29 459 18 08 ou eg 95 55 699 5 999 5 ove 25 ce 5 2 05 ae 67 as fer 99 ag 9 84815 sos E Su38MON 09391 4 et 22078 WNINH3L j ELE eut me 2 99 peor CA mu La 3 69 ge ut 00S angi gf ae Maien 1 8053 W31YA ONUIIN3 60S ie 7 Y 605 dM31 3015170 wie EEN 20 6 0 io t gt Y Hz 080 Y n 1 2 sU 105 901 01 t T 301190 1538 01 1432434 mist 95908 BAWA NO ISNYEX3 5 21000193732 e z 9053 Ze 230 0015 1670009 ap 014205 034 2 908 099 0 v RSA Axa d 755384 aoo 205 0 1 24 We ig em Ms Ce Ou NOLONS 015 Le 293 79831 3 ONON GIS Ze ANIL 3NI 3081109 LINN 339 ivi 41 VAPE nu iv 73A DIR 28 04 380 W3425 O 41 Agel ee 08 OS OMOYIS 335 H 47 09908 104100 H D E za 559 isa a Ae a web su km 00 LN Kn d Loze et 297
25. M24 M25 m Condenser Fan 4 Circ 2 M25 Liquid Solenoid Valve Cir 1 Liquid Solenoid Valve Cir 2 Spare S pare Table7b Digital outputs 3 compressor unit Alarm Circuit Table7c Digital outputs 4 compressor unit Alarm Circuit Chilled Water Pump Relay EXV Control Chilled Water Pump Relay EXV Control EXV Control EXV Control Compr 1 Contactor Compr 1 Top Solenoid Valve Compr 1 Contactor Compr 1 Top Solenoid Valve Compr 1 Bottom Right Solenoid Valve feed Compr 1 Bottom Right Solenoid Valve feed Compr 1 Bottom Left Solenoid Valve vent Compr 2 Contactor Compr 1 Bottom Left Solenoid Valve vent Compr 2 Contactor CO MY U1 BY ej Compr 2 Top Solenoid Valve feed Compr 2 Top Solenoid Valve feed m e Compr 2 Bottom Right Solenoid Valve feed m Compr 2 Bottom Left Solenoid Valve vent Compr 2 Bottom Right Solenoid Valve feed Compr 2 Bottom Left Solenoid Valve vent A w m Condenser Fan Contactor 12 m Condenser Fan Contactor 12 m LA Condenser Fan Contactor 13 m A2 Condenser Fan Contactor M 14 m LA Condenser Fan Contactor M 13 Condenser Fan Contactor M 14 m A2 m Condenser F
26. Restore power by closing CB1 If the output load remains energized when there is no relay in the socket the output s MOV has failed and thus the Output Board must be replaced If the output load de energizes the relay that was pulled is defective Contact chatter Contact chatter is very rapid opening and closing of con tacts It is usually caused by low voltage at the electrome chanical relay orcontactor coil If contactchatteris occurring on relay orcontactor connected to one ofthe Output Board 33 solid state relays itis also possible that a faulty connection exists on the power supply terminals of the Aux Out plug connector on the MCB and the Output Board In very rare instances contact chatter can be caused by a faulty solid state relay Perform the following procedure to isolate the problem 1 Verify that the voltage at the load s power supply and at the solid state relay contacts is adequate 2 Remove powerfromthe controllerby opening CB1 Swap the suspect relay with a known good relay Try to choose arelay that will notaffect unitoperation Restore powerby Troubleshooting Solid State Relays As shown on the unit wiring diagrams the solid state relays on the Output Boards all have normally open contacts Actually these contacts do notexistas they do in electrome chanical relay Instead of using contacts to switch the load the solid state relay changes its resistance from low closed when it is energized
27. WaitFlooded lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx M enu 3 Circ 2 satus OFF SystemS w ManualMde Alarm PumpDwnSw CycleTime xx WaitFlooded lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx IM 549 M enu 4 Water temp s Lvg xxx x F C Short F C Open F C Ent xxx x F C Short F C Open F C Ent Cond xxx x F C Short F C Open F C Lvg Condz xxx x F C Short F C Open F C Evap xxx x psi kPa xx F C Evap 145 psi kPa Open N A F C Short N A Cond xxx x psi kP a Cond 450 psi kPa Open N A F C Short N A MinCondPr 0 MaxCondPr 0 EXV Position xxx Cond Fan Stage x Evap xxx x psi kPa xx F C Evap 145 psi kPa Open N A F C Short N A Cond xxx x psi kP a Cond 450 psi kPa Open N A F C Short N A 8 4 E 5 M enu 7 Circ 1 T emp s Satur Evap xxx F C N A C SuctLine xxx x F C Short F C Super Ht xxx x F N A Satur Cond xxx F C N A
28. ground terminals Refer to Table 13 for the correct voltage levels If no voltage or improper voltage levels are found verify that the controller is energized 4 Check for proper communication trunk voltages at the field wiring terminals if any or directly on the connector The trunk must not be connected to the controller when you do this If no voltage or improper voltages are found check the wiring between the port terminals and the field terminals if any using Table 13 and Figure 22 verify thatthe three conductors are properly terminated in the network com munications connector If there is still a problem verify that the level 1 controller is energized and that the com munications trunk wiring is intact 5 Plug the network connector into port B 6 Verify communications have begun between the level 1 controller and the level 2 controller To verify communications using Monitor for Windows software network diagnostics must be performed To run network diagnostics selectthe pull down menu Comm Select Network Diagnostic which will then display the Network Diagnostics Parameters Setup dialog box Using the Network Diagnostics Parameters Setup dia log box you can choose to continually loop the diagnos tics or have a single sweep of each controller being connected to the network You can also perform the following functions Display Program ID and status Restrict display of level 3s to units with erro
29. 61 CHW flow switch EC er Bo by others 19 LAs Factory supplied TB5 alarm field wired Alambel of TM E ri AGND option Alafm bell 102 Output relay 0 f max 1 5 amps p y s 24 VAC EE e e 107 35 Be eg 70 IM 549 PFS Field Wiring 0719835C 01 Disconnect Unit main by others terminal block GND lug phase 4 2 00 4 To compressor s supply 4 1 Fused control circuit transformer option Disconnect by others Nos aT EE 10A use 120 VAC control power T el ees cee 1 by others 545 Note For single condenser pumpstarter applications D 9 field jumper terminals 11 amp 12 BP then field wire single starter d between terminals 11 16 7 24V or 120 by others rr 48 9 Solid state relay Output relayi 24V or 120 4 e 1 5 amps max CHW pump relay L DA by others N TB4 Sun Jegen by others impedance ey 46 Inherent in Lt MicroTech 4 20MA for 47 GND controller demand limit pud 9 250 a load by others impedance 1 CLR 5232 TR Connection to RS232 50 Communication for modem or
30. If no voltage or improper voltage levels are found verify that the panel is energized 4 Plug the network communications AMP connector into portB Level 2 controller connection This procedure will verify that proper communications have begun for each controller as it is connected to the network You can connect the level 2 controllers in any order how ever it is better to follow the daisy chain as you proceed This will make troubleshooting easier if communications problems occur As a result of the previous procedures the network communications connector should be disconnected from the B port at every controller on the trunk except for the level 1 controller Be sure that this is true before beginning this procedure Forcommunications to occur each networked controller must have the proper hex switch setting and the proper voltages at its port B terminals 1 Set the network address hex switch setting to match the address on the engineering schedule Each controller must have a unique address 35 2 Turn on power to the level 2 controller Refer to the controller installation manuals for information on how to turn on power to each controller 3 Check the voltages of port B directly on the AMP connec tor The trunk must not be connected to the controller when you do this UseaDC voltmeterto test for proper voltages With the ground lead on the control panel chassis ground check the voltage at the and
31. Pa 060 2 Mink 50 ox 3 30023 besdBandMut xx s StageUpen ox 400 30090007050 StseDnErzx 1001690 30 00 40 2760 Note indicates Centigrade values IM 549 47 M enu 21 D emand limits Screen D isplay Factory Set Point 1 Demand Lim xstg Not Changeable at this screen DemandSg xx x ma Actual Value Indicates the Magnitude of the Demand Limit Signal M enu 22 Timedate Screen D isplay Factory Set Point xxoo xx Actual Time Mon xx xx xx Actual Day and Date M enu 23 Schedule Screen ___ _______ 2 NwPSchedue N k NA E E 1 000023585 1 00009359 Mon00902359 00062358 00009359 5 Tue 00 00 2359 00002359 00009359 Wea 00 00 7359 00002359 00009359 00002359 90992339 s 2000023559 00002358 90902359 M enu 24 H oliday date 1 Hbowe NAO f 3 Pa euro days
32. PumpDown sequence As the evaporator pressure falls be low the StopPumpDownPres set point while pumping down 26 the compressors and condenser fans will stop If the evapo rator pressure is greater than the StopPumpDownPres set point after 180 seconds have elapsed the compressor will stop and the display will read Can t Pump Down Thealarm output will be activated IM 549 M anual Pumpdown When the compressor is running and the circuit pumpdown switch is moved from the Auto position to the Stop position the circuit will pumpdown and stop when the evaporator pressurefalls below the StopPumpdownP ressure Set point When the compressor is not running and the circuit pumpdown switch is moved from the Auto position to the Stop position the controller will initiate a pumpdown only if the evaporator pressure is above the Begin Pumpdown Pressure set point The compressor will stop when the Service Pumpdown The normal pumpdown sequence will stop when the evapo rator pressure equals the Stop Pumpdown set point pres sure A control set point called FullPumpDown has been provided which willallow an extended pumpdown forservice purposes The default value for the FullPumpDown set point 5 No By changing this setting to Y es the circuit will attempt to pump down to 2 psi during the next pumpdown cycle If 2 psi Safety Systems System Alarms Alarm conditions which are common to both refrigerant circuits are consid
33. Sensor Compr 3 No Liquid Liquid Motor Prot Compr 3 Alarm Normal Not Used Not Used Phase Volt Monitor Compr 2 Normal Phase Volt Monitor Compr 3 Normal PumpDown Switch Compr 3 Normal 0 1 2 3 4 5 6 7 8 9 m e m m m LA m A m m o m m m IM 549 15 Table5c Digital inputs 4 compresor unit CERN Mechanical High Pressure Switch Cir 1 Alarm Normal Liquid Presence Sensor Compr 1 No Liquid Liquid Motor Prot Compr 1 Alarm Normal Not Used Not Used S ystem On Off Switch Phase Volt Monitor Compr 1 Alarm Normal PumpDown Switch Compr 1 Normal Pump DN Mechanical High Pressure Switch Cir 2 Alarm Normal Liquid Presence Sensor Compr 2 No Liquid Liquid Motor Prot Compr 2 Alarm Normal Not Used Not Used Remote Start Stop Switch Stop Start Evap Water Flow Switch No Flow Flow PumpDown Switch Compr 2 Normal PumpDn Mechanical High Pressure Switch Cir 3 Alarm Normal Liquid Presence Sensor Compr 3 No Liquid Liquid Motor Prot Compr 3 Alarm Normal Not Used Not Used Phase Volt Monitor Multi Point Alarm Normal Not Used PumpDown Switch Compr 3 Normal PumpDn Mechanical High Pressure Switch Cir 4 Alarm Normal Liquid Presence Sensor Compr 4 No Liquid Liquid Motor Prot Compr 4 Alarm Normal Not Used Not Used Not
34. Staging D own Lead 9 Lag2 Compressor Compressor N bi w N e Two Compressors Available Staging U p Lag 3 Unit Compressor Capacity Staging D own Lead 9 2 Compressor Compressor One Compressor Available Staging U p U nit Capacity Staging D own Lead Compressor Project Ahead C alculation The Project Ahead Calculation provides protection against an overshoot condition when the chilled water temperature is outside the control band During cooling mode if the Chilled Water Temperature is abovethe control band and the rate of temperature reduction is so great that in 120 seconds Interstage T imer The minimum time delay between stage up commands is set by the interstage timer set point default 210 sec The Anti C ycle T imer Anti cycle timers are used to protect the compressors from excessive starts and high motor winding temperature The Compressor H eater C ontrol Compressor Heater Control for PFS units is based on the suction line superheat If the superheat reading drops below IM 549 the chilled watertemperature will be below the control band the controller will stage down The Project Ahead Calcula tion also moderates the controllers response to a rapid increase in leaving water temperature interstag
35. acceptable lift pressure is determined by the expansion valve At low tonnage capacities a minimum lift pressure of approximately 60 psid must be maintained At higher tonnage capacities a higher lift pressure must be maintained to provide proper refrigerant flow through the expansion valve Refer to the following table for the lift pressure values maintained at various unit capacities Indi vidual head pressure set points are provided at 2596 50 and 100 circuit capacity to optimize chiller operation For operation at 7596 capacity and greater with outdoor air temperatures less than 60 F the minimum lift will automati cally be reset downward The maximum available reset at Figure 13 Min list SPT at 10096 10096 capacity is 40 psid while the maximum reset at 7596 capacity is 20 psid Table 10 60 psig 60 100 70 psig 70 100 105 psig Fixed 140 psig 100 140 Area of reset based on OAT 140 105 2 Low limit for min lift SPT E 69 at 10096 E 60 25 50 75 100 Compressor capacity Lift Pressure D ead Band The MicroTech controller establishes a dead band above the minimum lift pressure that varies with circuit capacity If the lift pressure is within the dead band no fan staging will occur 11 Condenser fan staging will follows for lift pressures above or below the dead band D eadband T able N o Spee
36. and custom report software h 101 Enhanced Keyboard Required for more advanced functions of the operator interface and custom report software i The computer shall include MS DOS 6 2 or greater Windows 3 1 or greater and all owner s manuals j The computer shall have an internal time clock that is battery backed to maintain system time and date k Thecomputershall have an internal 9600 Baud Hayes compatible modem if remote access and monitoring of the MicroTech unit controller is desired The modem shall be addressable as Com1 Com2 37 2 Multisync Super VGA Color Monitor For use with the Super VGA graphics 3 Printer 192 CPS Characters Per Second EpsonLQ 510 or equivalent Must have the ability of supporting IBM extended character graphics 4 PrinterC able 6 Ft Parallel Forcommunications connec tion between the PC and the printer The computer is used for changing set points monitoring data trend logging diagnostics and remotely clearing alarms within the MicroTech system The computer is normally a dedicated personal computer however the operator may choose to exit the Monitor program from time to time to perform other functions such as word processing or data manipulation using a spreadsheet program It should be icroT ech M enu Structure A complete listing of the information stored in the MicroTech controller tree structure is shown in the following tables This table shows the menu
37. by opening CB1 Try to improve the connections in the Aux Out plug insulation displacement terminals by pressing down on the wires with a small screwdriver 4 Check all other wiring and connectors for bent pins or miswires If the chatter does not stop the electromechanical relay or contactor is probably defective the difference is that there is an open set of contacts or a disconnection between the relay output and the load In this circuit a solid state relay will not behave like an electrome chanical relay If the solid state relay is energized the relay output will be hot as expected However if the solid state relay is de energized the relay output will still appear to be hot This is because the relay output and the voltmeter form a continuous circuit in which the relay s resistance though high is insignificant compared to the voltmeter s resistance This means that nearly all the voltage is dropped across the voltmeter Therefore the voltmeter indicates that voltage is present If a low wattage light bulb of the appropriate voltage is used instead of a voltmeter the bulb s low resis tance will load the circuit enough to eliminate the false voltage indication In this situation an incandescent test lamp is a better tool than a voltmeter Figure 17b T eting typical rday circuit with a disconnection Output board Neutral J ob specific Monitor software includes each unit and auxiliary controller s program Th
38. communication standard with a maximum cable length of 50 feet All communication network wiring utilizes low voltage shielded twisted pair cable See the Personal Computer Specification section of this manual for specific hardware requirements Communication port B is used to link the unit controller into a MicroTech network using the RS 485 communication standard Referto the field wiring drawing in this manual for details IM 549 Modem Kit An optional modem kit may be installed for remote monitor ing of the chiller from an off site PC running McQuay s Monitor software The kit comes complete with modem wiring harness and installation instructions Remote monitoring ofthe MicroTech controller requires a dedicated telephone line supplied by the equipment owner The McQuay Monitor software package used to establish a remote connection to the modem kit must be purchased separately Unit Sequence of O peration The following sequence of operation is typical for McQuay ALS air cooled and PFS water cooled chillers The sequence Off C onditions With power supplied to the unit 115 VAC power is applied through the control fuse F1 to the compressor crankcase heaters the compressor motor protector circuits the pri mary of the 24V control circuit transformer and optionally the evaporator heater HTR5 The 24V transformer provides power to the MicroTech controller and related components With 24V powerapplied the controller will chec
39. kPa 4 Cond x x psi kPa 5 SuctLine2ox x F C 6 LiquisLin xxx x F C Lvg xxx x F C 8 Outsid eA xxx x 3 RRE 19 Fran Stage x 00000 M enu 34 4 curr alarm 1 2 999 00998 3 kPa 4 kPa 5 SuctLine xxx x F C ___6 LiquisLn xxx x F C Evap Lvg xxx x 8 CR EE REES IM 549 M enu 35 1 prev alarm Screen Curent ___________ 3 RES x ox Curent Alarm M enu 37 3 prev alarm Screen Pt Curent Pt xox CCS 3 Pax xox S Ps Current Alarm 6 xx 8 _SCurrent Alarm M enu 36 2 prev alarm Screen Current Alarm Ce SCS ____ _____ M enu 38 4 prev alarm Screen Pt f oS E RES Current Alarm 8 scwrenAam IM 549 59 Schematics and D rawings ALS PFS Wiring D iagrams Table 15 Control Cabinet Layout Wiring Legend Unit Control Stag
40. keypad by the operator before any set points may be altered Tablel Unit Identification ALS Air Cooled Chiller with Screw Compressors PFS Water Cooled Chiller with Screw Compressors IM 549 Control Panel Features Flexible control of leaving chilled water with convenient reset capability Enhanced head pressure control on air cooled units resulting in increased total unit SEER Convenient easy to read 2 line by 16 character display for plain English readout of operating temperatures and pressures operating modes or alarm messages Keypad adjustment of unit safeties such as low water temperature cutout high pressure cutout suction pres sure cutout and freeze protection The operator can use the keypad to monitor various operating conditions set points or alarm messages Security password protection againstunauthorized chang ing of set points and other control parameters Complete plain English diagnostics to inform the operator of system warnings and alarms All alarms are time and date stamped so there is no guessing of when the alarm Software Identification Controller software is factory installed and tested in each panel prior to shipment The software is identified by a program code which is printed on a small label attached to the controller The software version may also be displayed on the keypad display by viewing the last menu item in the Misc Setup menu SC 3 2
41. opening circuit breakers or by disconnecting the 3 phase power before beginning tests Failure to do so can result in severe compressor damage Service Test D igital O utputs Select control mode menu 13 and set the chiller s control mode to Service Testing Select menu 22 and with the Prev or Next item keys select the digital output you wish to test Enter the service password when prompted by the display Pressing the Inc key will turn the selected output on pressing the Decr key will turn it off All outputs except 1 2 4 and 8 will remain in their last commanded state until the Service Testing Service test D igital Inputs Select control mode menu 13 and set the chiller s control mode to Service Testing Select menu 22 and with the Prev or Next item keys selecttest 16 DH1 The current state of the first 8 digital inputs 0 7 will be represented on the keypad display as a row of ones or zeroes where 1 equals on and 0 equals off By manipulating field wired devices system switch motor project etc and watching the key pad display the status ofthe first eight digital inputs can be verified Keypad D isplay O verview The information stored in the MicroTech controller can be accessed through the keypad using a tree like structure This tree structure is divided into Categories Menus and Menu Items There are three categories which make up the Status C ategory Menus and menu items in this category provide in
42. test for stray voltage throughout the trunk Note If you get a 2 or 3 Vdc reading it indicates that one or more powered controllers are connected to the trunk These controllers should be located and discon nected 2 Verify that there are no shorts between any two conduc tors Use an ohmmeter to test for shorts at field wiring terminal block or directly on the port B connector of the level 1 controller Forthe three combinations of conduc tor pairs there should be infinite resistance between the conductors If the conductors are properly terminated this check will test for shorts throughout the trunk N ote If you find a resistance that is high but less than infinite it indicates that one or more non powered con trollers are connected to the trunk These controllers should be located and disconnected 3 Verify that the communications wiring is continuous over the trunk and that the field terminations are correct This step is optional but recommended to do it you must know the physical layout of the network s communica tions trunk Go to the last controller on one end ofthe daisy chain and place a jumper across the to ground and to ground Remove the jumper and repeat this step for the other two conductor pairs to ground and to ground Ifthere is continuity foreach conductor pair the wiring is continuous and itis likely but not guaranteed that the terminations are correct throughou
43. to high open when it is de energized This high resistance is approximately 100K ohms Because the output circuit through the solid state relay remains con tinuous regardless of whetherthe relay is energized trouble shooting a solid state relay with a voltmeter can be tricky In a typical circuit a power source is connected across a single relay output and a load see Figure 17 In this circuit a solid state relay will behave like an electromechanical relay If the relay is energized the relay output will be hot If the relay is de energized voltage cannot be measured relay output The circuit shown in Figure 6 is similar to a typical circuit Figure 17a T eting typical rday drauit 115 VAC Output board Neutral MCB Replacement If an MCB board is defective and must be replaced the proper controller software must be loaded into the replace ment MCB This can be done either at the factory or at the building site if a PC equipped with appropriate Monitor software is available The factory will download the proper controller software into a replacement MCB board before it is shipped if you include the program code with the replacement MCB part order If the program code is not provided the MCB board will be shipped without software 34 closing CB1 If the chatter does not stop go to step 3 If the chatter stops the suspect relay is defective Replace the relay 3 Remove powerfrom the controller
44. 276 1904 180 326 1242 2249 Note indicates Centrigrade values IM 549 57 M enu 30 Misc setup D isplay Factory Set Point Unit Type ALS300 ALS315 ALS330 ALS340 ALS360 ALS370 ALS 380 2 English English English M etric 3 Power 60h2 60 50 5 Port A Baud xxxx 9600 9600 2400 1200 Pre Alarm Blink Open Closed Alarm Closed Blink N O Blink N C OAT Select None Blink Open Closed Closed Blink N O Blink N C None Lcl Rmt Rmt Amb Lockout No Yes id 08080409 E E OCI ea S E E ndAd psa 0 0 5 2929138188 202038138 Remgeant R22 Nt Changeable PENT sca Netehengeabie M enu 31 1 curr alarm Cond x x psi kPa SuctLine xxx x F C LiquisLn xxx x F C Evap Lvg xxx x F C OutsideA xxx x F C Fan Stage x M enu 32 2 curr alarm D isplay 0 00 0 00 00 Evap x x psi kPa Cond x x psi kPa SuctLine xxx x F C Fan Stage x 58 0 E T o a M enu 33 3 curr alarm 3 93 00980 3 Evap xxpsi
45. 760 300990 0070683 100 690 50 400 340 2760 Note indicates Centrigrade values M enu 23b H ead presspt valuesfor 134a refrigerant 25 GE 3 BesBandMutexx 7 5 SmgeUpemexx 40076 300399 0070683 100 690 50 400 840 2760 Note indicates Centrigrade values M enu 24 Demand limits Display Factory Set Point Demand Lim xstg Not Changeable at this screen Indicates the Magnitude of the Demand Limit Signal DemandSg xx x ma Actual Value M enu 25 Time date Display Factory Set Point El 2 1 M enu 26 Schedule ___ ______ 2 NN Schedule WA E 00002359 1 00009359 Mon 00100 2359 00002355 00009359 5 Tue 00 00 2359 00002359 00009359 Wes0530558 00002359 00009359 00002359 00009359 s 00002359 00002359 00009359 IM 549 55 M enu 27 H oliday date ____ ____ mao ___ _
46. 84 78 278 243 284 o NOTE TERMINAL BLOCKS ARE SHOWN WITH STANDARD UNIT WIRING ADDITIONAL WIRES MAY BE CONNECTED FOR NON 5 CONTROL OPTIONS 65 ech 717000D 01 icroT PFSM QNO 15 631202 Sham WMOLLIOON 140 NONIS MOMS Tv 12079 WNAI 1310N 1897049 908796 09872989 DNH 9 262162 541 ma ime 24 H 106 69 210718 99 LO nua 99 59 9 659 69 858 159 958 LEI 692 899 088 9 9 ae er 4 8 v 98 2v vie sig Sv 196 508 zeh VW EA ve ng LOCH vier m e 216682 Du ute ec be Cd 950 7 ost 66 0 erg zee o 606 eee 806 vee ze 186 91 1 0L 506 rot 10 oot SAJIN Ovil 4 2018 WNINYIL 1N02 258 teg 734 734
47. ANE TB3 TERMINAL BLOCK 120V RL BOX CTRL PANEL UARDISTOR RELAY L BOX CTRL PANEL 4 5 TERMINAL BLOCK CONTROL GFP ROUND FAULT PROTECTOR L BOX POWER PANE 24V OR LESS RL BOX CTRL PANEL GRD GND ROUND L BOX POWER PANE TBIO TERMINAL BLOCK FAX ALARM CTRL BOX CTRL PANEL HGR1 HGR2 HOT GAS RELAY RL BOX POWER PANEL TD5 TD7 TIME DELAY COMPR REDUCED INRUSH CTRL BOX CTRL PANEL HTRI HTR3 COMPRESSOR HEATER COMPRESSORS 5 HEATER EVAPORATOR WRAPPED AROUND EVAP JI JI8 JUMPERS LEAD RLBOX CTRLPANEL JB5 JUNCTION BOX EVAP HEATER NEAR EVAP ON BASE RA WIRING SYMBOLS KEYPAD KEYPAD SWITCH amp DISPLAY RL BOX KEYPAD PANEL 2 LPSI LPS3 LIQUID PRESENCE SENSOR COMPRESSOR POWER WIRING FACTORY INSTALLED SHIELDED AND MI M7 CONTACTORS COMPRESSOR LBOX POWERPANEL POWER WIRING FACTORY INSTALLED JACKETED PAIR 37 CONTACTOR FAN MOTORS L BOX POWER PANEL MCB250 MICROTECH CONTROL BOARD 250 L BOX CTRL PANEL POWER WIRING FACTORY INSTALLED OPTION MHPRI MHPR3 MECH HIGH PRESSURE RELAY TROL BOX CTRL PANEL BLOCK MECHANICAL JUMPER L BOX CTRL PANEL MODEM MICROTECH MODEM FAX MPRI MPR3 MOTOR PROTECTOR RELAY MTRII MTR37 MOTORS CONDENSER FANS NEUTRAL BLOCK OUTPUT BOARD MICROTECH OVERLOADS OIL SAFETY SWITCH PBI PB3 POWER BLOCK MAIN CO CS CT DS1 DS2 EXV BRD FI F2 FB5 FB6 FBI5 GDI GD3 nmocoooooono 23 22 21 27 5 25 0 0 20 r 2 R CONTROL BOX TERMINAL FIELD CO
48. F C Short F C M enu 19 Control mode M enu 15 Chiller amps 163 PctRLA xxx 264 PctRLA xxx M enu 16 Comp run hours E 55 9255 93 6 50 8 2100 6 259600 10 2 50 Kxxxxx 87559 12 34261009 13 somo 0000 14 34365000 00 16 1430100595 18 4 505 00000 20 4 1005 M enu 17 Compr sarts 3 M enu 18 Air temp Screen Display 1 OutDoor xxx x F C D isplay Factory Set Point Manual Unit Off Automatic Manual Staging Service Testing Manual Unit Off ManualStagesmx 12202002 3 ERR Aute 5 Ao s Auto RTE IM 549 53 M enu 20a Lvg evap spts valuesfor R 22 refrigerant ERR RER Not Changeable 0 E 6 MaxPullDn x x F C 5 0 2 0 1 1 0 0 0 0 5 ResetO pt None Return 4 40 Ma Network Ice Outdoor
49. HI 21 MONT IAr e D z l1 2U2 AS 75538448 WIRD 1 M Eg 158 Uu 2 gt 27 M ma f z c Ze 38O WOSNIS 39435349 OO 36 MOSNOS 54 9 r ae DES CR WO i Mec Vw 55344 e E Mau ER 9 t 4 Ze AS DER S 045 158 16 M 2800 1 La Monin 013 4 04 3108 Ee ER HOLS 4015 310938 2 Sep is GEET LE be ch 658 4 589 999 SS EA 956 tm 0 08 88 08 4 44 086 DI gt wg 734 Ab At SE 034 734 tzo IM 549 66 ALS Unit Control 0716995D 01 LINE CONT TERMINAL BLOCK amp LEAD NUMBERS 20 w 60 1 1 NB 504 4 505 P CZ C 506 M 100 ox DA RECEPTACLE F3 re NOTE S acm NOTES FOR FELD WING HIR 5 TO aNoTHER 549 CRCUT REMOVE WIRES 540 ANO 545 2 5 Te 542 543 t Sr ERIE a 545 203 EI 5 2 577 802 8 M _ 5 1 sexum eww hon sj 7i t 70 d 5 9345 3222 1255
50. Hardware Screw Chiller Number of Compressors Refrigerant 2 R22 3 R134a IM 549 condition occurred In addition the operating conditions that existed atthe instant of shutdown can be recalled to aid in isolating the cause of the problem Softloading feature to reduce electrical consumption and peak demand charges during chilled waterloop pulldown Easy integration into building automation systems via separate 4 20 milliamp signals for chilled water reset and demand limiting M cQuay s Open Protocol feature is fully supported Flexible internal time clock for on off scheduling Communications capabilities forlocal system monitoring changing of set points trend logging remote reset alarm and event detection via compatible PC The optional modem kitsupports the same features from an off site PC running McQuay Monitor software Specialservice modes may be used to override automatic unit staging during system checkout and service The software version is the 5th amp 6th digit of the software number In the example the version is 17 and the revision to the software is G Revisions are released in alphabetical order 19 A Software Revision Version English Controller Layout All major MicroTech components are mounted inside the control section side of the unit s control cabinet The indi vidual components are interconnected by ribbon cables shielded
51. M enu 3 Circ 2 satus SystemSw ManualM de Alarm PumpDwnSw CycleTime xx WaitFlooded lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx M enu 4 Circ 3 satus Screen Screen ManualM de Alarm PumpDwnSw CycleTime xx WaitFlooded waitF lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart IM 549 M enu 5 Water temp s Display Lvg xxx x F C Short F C Open F Ent Evap xxx x F C Short F C Open F C Ent Cond xxx x F C Short F C Open F Lvg Cond xxx x F C Short F C Open F M enu 6 Circ 1 press Evap 145 psi kPa Open N A F C Short N A F C Cond 450 psi kPa Open N A F Short N A F 3 WmConPPrz 0 0 5 6 Cond Fan Stage x M enu 7 Circ 2 press Evap xxx x psi kPa xx F C Evap 145 psi kPa F Open N A Short N A Cond xxx x psi I XXX Cond 450 psi Xxx N A F 9 Short N A 3 MiCendPr 0 0 5 PwPoson xw 6e _______ M enu 8 Circ 3 press xxx x psi kPa xx F C Eva
52. NEL ANALOG DIGITAL INPUT BOARD L BOX CTRL PANEL PVMI PVM3 PHASE VOLTAGE MONITOR CTRL BOX POWER PANEL ANALOG OUTPUT BOARD L BOX CTRL PANEL RES1 RES2 RESISTOR CURRENT TRANSFORMER CTRL BOX POWER PANEL SURGE CAPACITOR COMPRESSOR L BOX POWER PANEL SI SWITCH MANUAL START STOP CTRL BOX KEYPAD PANEL CAPACITOR SPEEDTROL DE SPEEDTROL BOX 801 8021 8031 SPEED CONTROL INSIDE SPEEDTROL BOX RCUIT BREAKER POWER L BOX POWER PANEL SIG CONV SC SIGNAL CONVERTER TRL BOX CTRL PANEL RCUIT BREAKER MICROTECH L BOX CTRL PANEL SVI SV2 SV7 OLENOID VALVE LIQ LINES N LIQUID LINES RCUIT BREAKER FAX ALARM L BOX CTRL PANEL SV3 SV4 SV8 OLENOID VALVE LIQ INJECTION N COMPR LIQ INJ LINE HILLED WATER INTERLOCK D INSTALLED SV5 SV6 SV9 OLENOID VALVE HG BYPASS N LINE TO HOT GAS VALVE OMPRESSORSI 3 BASE RAIL TI RANSFORMER MAIN CONTROL RL BOX POWER PANEL OMPRESSOR SOLENOID COMPRESSOR T2 T5 T7 RANSFORMER 120 TO 24V CONTROL RL BOX CTRL PANEL URRENT TRANSFORMER RL BOX POWER PANEL T8 RANSFORMER 575 TO 208 230V RL BOX CTRL PANEL SCONNECT SWITCH MAIN L BOX POWER PANEL SPEEDTROL LECTRONIC EXPANSION VALVE BOARD L BOX CTRL PANEL TA4 T6 RANSFORMER 24 TO 18V CONTROL RL BOX CTRL PANEL USE CONTROL CIRCUIT L BOX SWITCH PANE TIO RANSFORMER 208 240 TO 24V OR RL BOX CTRL PANEL USE COOLER HEATER L BOX SWITCH PANE 460 TO 24V SPEEDTROL USEBLOCK CONTROL POWER BOX POWER TB2 TERMINAL BLOCK 120V FIELD RL BOX CTRL PANEL USEBLOCKS FAN MOTORS L BOX POWER P
53. NN USAGE L BOX CTRL PANEL CONTROL BOX TERMINAL FACTORY USAGE e THERMISTOR R L BOX CTRL PANEL TROL BOX CTRL PANEL UNINDENTIFIED COMPONENT TERMINAL DIODE DENSER SECTION INDENTIFIED COMPONENT TERMINAL CAPACITOR L BOX CTRL PANEL L BOX CTRL PANEL Z WIRE NUT MOV L BOX POWER PANEL CZ VARISTOR BOX CTRL PANEL MANUAL RESET CONTROL VM BOX POWER PANEL 4 AUTOMATIC RESET CONTROL IM 549 63 PFS Unit Control 0716998D 01 TERMINAL BLOCK amp LEAD NUMBERS LINE NO 120 60 1 M F1 i MOV 504 503 506 1200 TSOVAC 2 4 228 5 128v MJ 46 801 5 802 807 WHT gt 508 B 204 ead T2 M 56 66 x 205 875 24 POWER e R LAY 0 1 100 INPUTS SEE MCROTECM a wy one Et 206 SCHEM LINE 2345 22252 140 M 875 120VAC POWER COMPR SOL RELAYS SEE STAGING SCHEM LINE 9415 LS AMPS 24 E T wrAUx 1 40 j 18 208 145 19 209 1 COMPR 52 26 NO 1 E ns 20 22 NN RELAY 1 9 160 162 otko 161 29 NOTE ON UNTS WITH 380 415 460 575V xal INRUSH OR WHEN 0 5 15 N
54. OT ON THE UNT 220 6 WIRE 61 15 CONNECTED 73 TOS asec 1 GT an 120 TO T7 FOR EXPANSION VALVE BOARD REMOVE WIRE 2146 896 SEE MICROTECH SCHEM LINE 9552 2 3 Cura 1 leri 28 240 SH 241 24 252 242 COMPR 2 B NO 2 243 248 20 2 2s0 2 32 o 29 oe 33 G 21 MJ 260 257 H 0 262 261 23 258 NOTE o UNTS WITH 0 415 480 278 WHEN OLG IS NOT ON THE UNI 252 WIRE 9261 IS CONNECTED TO 253 INCOMING FIELD POWER 24V OR 120V 60 1 eS 270 3 1 27 29 320 7 aw 44 11 240 m ou 300 70 10 124 114 151 161 146 173 150 SEE 5 FOR COMPLETE TERMINAL 185 UST FOR Tes 515 878 22 830 56 102 671673 EI femen E NO TOP ROW 506 547 000000000 NOTE TERMINAL BLOCKS ARE SHOWN WITH STANDARD UNT WIRING ADDITIONAL WIRES m CONNECTED FOR STANDARD CONTROL OPTIONS IM 549 PFS 8 Stage O utput 071699D 01 LINE CONT TERMINAL BLOCK NO NO amp LEAD NUMBERS SEE UNT CTRL SCHEM FOR COMPLETE TERMINAL NO 2 LIST FOR TB2 120 60 1 FROM UNT CTRL SCHEM REG FROM 00 77 MCB250 AUX OUT 0B SEE MCROTECH SCHEM touTput 2 MCB258 43
55. OUPR 2 BOT LEFT SOL VENT 20 e 13 154 CONDENSER CONTACTOR MI2 155 A423 CONDENSER 158 424 CONDENSER FAN 4 425 CONDENSER CONTACTOR MIS SEE UNIT CTRL 3 SCHEMATIC e 235 254 CONDENSER CONTACTOR M22 256 n CONDENSER 23 258 428 CONDENSER CONTACTOR M24 264 429 CONDENSER 25 ii gt OPEN FUTURE RELAY 21 OPEN FUTURO RELAY 22 OPEN FUTURE RELAY 23 37 OPEN FUTURE agas 68 TERMINAL BLOCK amp LEAD NUMBERS SEE UNT CTRL 5 FOR COMPLETE TERMINAL NO UST FOR 1782 TB2 16 100 875 200 e 509 ALSO SEE SCHEMATIC ISEE SCHEM FOR COMPLETE TERMINAL NO UST FOR T8445 784 pes 185 sear 102 671 875 105 NB BOTTOM ROW 43 164 5 178 278 243 284 o NOTE TERMINAL BLOCKS ARE SHOW WITH STANDARD UNIT WIRING ADDITIONAL WIRES MAY CONNECTED FOR NON STANDARD CONTROL OPTIONS IM 549 ech 2 Compressor Unit 716997D 01 icroT ALSM mes weary VONIS MON 93123405 13104 ms nma na tame Ceg xg 298 718 49 99 NYG 69 9
56. SE Aen 5 MICRO f Z CONTROL 873 B 8 SCH 5 874 s M 403 81 107 9 875 881 9 00 206 ALARM CIRCUIT UNT CTRL 9 10 SCHEMATIC 4150 SEE UNT CTRL 50 510 WATER PUMP RELAY lte SCHEMATIC OPEN ven for exv contRoL TRR See SEE MCROTECH SCHEMATIC 5 gt OPEN 26 174 183 2177 175 185 55 24 HOT GAS BYPASS D D CONTROL 9 9 U3 e SEE are 9 44 2928 25 SCHEMATIC 1 CONTACTORS d SY 6 26 cst 8 875 207 1 SOL tFEED ALSO SEE 27 Ce UNIT CTRL iU Oo 05 h 187 143 A SCHEMATIC RIGHT SOL FEED SP COMPRESSOR ei Cen 2 479 9 BOT LEFT SOL VENT N72 56 274 283 277 33 34 HOT GAS BYPASS HGRZ 37 275 285 SEE UNIT CTRL 1 26 iios 23 Lm mU 278 aw 251 250 38 276 286 39 142 279 38 277 274 4 49 40 242 280 2 SOL FEED y wO IP 420 COMPR 7 RIGHT SOL FEED FOR 478453 COMPRESSOR 2 184 276 e286 ale COMPR 2 LEFT SOL CVENT 39 90 062 CS 5 422 e sis 576 40 HTR 2 280 242 1 1 243 423 COMPR 92 In 873 OPEN FUTURE 424 SEN 87 57 OPEN FUTURE 425 IM 549 NB BOTTOM ROW 143 1
57. Tech keypad 29 Alarm Category Menus and menu items in this category provide information Display Format The information stored in the MicroTech controller tree structure can be viewed one menu and menu character LCD display The current MENU is shown on the top line and the current MENU ITEM is shown on the bottom line of the display The operator can select either English or metric engineering units Once the desired engineering units have been selected momentarily remove and restore powerto the MicroTech controller to complete the change regarding current and previous alarm conditions English Units Temperature F Fahrenheit Pressure Psi Pound per sq inch Psig Psid Metric Units Temperature C Centigrade Pressure Kpa Kilo Pascals Kpag Kpda icroTech Component Test Procedures amp ALS Units Status LED diagnostics The MCB status LED indications can aid in controller diag nostics If the status LEDs do not operate normally as described in the Component Data section of this handout see Tables 1 amp 2 there is a problem with the MCB Following are troubleshooting procedures for the various symptoms Red LED remains on If the red LED remains on after the 5 second self test period Troubleshooting Power Problems The MCB status receives 18 Vac center tapped power from a transformer It then distributes both 5 Vdc and 13 Vdc power to various Microtech components A problem that exis
58. Used Not Used PumpDown Switch Compr 4 Ble o gt w N m m m A m m o m m m On Analog utputs Table6 Analog outputs No Description Signa Range SpeedTrol Circuit 1 SpeedTrol Circuit 2 SpeedTrol Circuit 3 SpeedTrol Circuit 4 16 IM 549 Digital utputs Table7a Digital outputs 2 compressor unit No 0 Alarm LED and Contact Programmable Programmable Chilled Water Pump Stop Run EXV Serial Data 1 EXV Serial Data 2 MCR relay Compr 1 Stop Top Solenoid Compr 1 Hold Bottom Right Solenoid Compr 1 Hold Bottom Left Solenoid Compr 1 Hold MCR Relay Compr 2 Stop Top Solenoid Compr 2 Hold Bottom Right Solenoid Compr 2 Hold 0 1 2 3 4 5 6 7 8 9 10 11 Bottom Left Solenoid Compr 2 Hold m Condenser Fan 1 Circ 1 M12 m LA Condenser Fan 2 Circ 1 M13 m A Condenser Fan 3 Circ 1 M14 m Condenser Fan 4 Circ 1 M15 m o m Condenser 2 Circ 2 M23 m co Condenser Fan 3 Circ 2 M24 M13 M14 M15 Condenser Fan 1 Circ 2 M22 M23
59. X 4 via a ribbon cable umpers on the 4 determine what type of output will be sent to the analog output device The analog output signals are sent from the AOX 4 by connecting a two pin Phoenix connector to the Analog Output Ports on the AOX 4 Analog output device is not operating correctly Ifthe MCB appears to be functioning properly and the analog output device is not operating correctly perform the follow ing procedure 1 Try cycling power to the controller by opening and then closing circuit breaker CB1 2 Check the ribbon cable s power wiring from the trans former to the AOX 4 field wiring connections from the 32 connecting the suspect component and restore power after connecting the replacement component Ifthe prob lem persists it is likely that the MCB is defective closing circuit breaker CB1 2 Check the ribbon cable power wiring connector and the field wiring connections from the analog input device Look for bent pins cable on backwards or miswires Restore power after reconnecting all cables and wires 3 Ifthe problem persists try swapping aknown good ribbon cable an ADI board or analog input device Swap these components separately to isolate the problem Remove power from the controller before disconnecting the sus pect component and restore power after connecting the replacement component If the problem persists it is likely that the MCB is defective 1 Try cycling power to the co
60. acter display and keypad or by using an IBM compatible computer running McQuay Monitor software In addition to providing all normal operating controls the MicroTech controller monitors all safety devices on the unit and willshut the system down and close a set of alarm contacts if an alarm condition develops A CAUTION The McQuay MicroTech control panel contains static sensitive components A static discharge while han dling electronic circuit boards may cause damage to the components To prevent such damage during service involving board replacement McQuay recommends discharging any static electrical charge by touching the bare metal inside the panel before performing any service work CAUTION Excessive moisture in the control panel can cause hazardous working conditions and improper equip ment operation When servicing equipmentduring rainy weather con ditions the electrical devices and MicroTech compo nents housed in the main control panel must be protected The MicroTech controller is designed to operate within an ambient temperature range of minus 40 to plus 185 F anda maximum relative humidity of 95 non condensing Important operating conditions at the time an alarm occurs are retained in the controller s memory to aid in troubleshoot ing and fault analysis The systemis protected by a password scheme which only allows access by authorized personnel A valid password must be entered into the panel
61. actory Set Point i 50 MinLift 50 xxx 56 386 50 80 345 552 i 0 1 0 Notes indicates Centigrade values M enu 18 D emand limits D isplay Factory Set Point LL Demand Lim Not Changeable at this screen DemandSg xx x ma Actual Value Indicates the Magnitude of the Demand Limit Signal M enu 19 Time date Pt mene Aewsbsy and Date IM 549 41 M enu 20 Schedule ___ _______ NwPSchedue N jk 31 5 00 259 00002359 90992389 Mon 00100 2359 00002358 Tue 00 00 7359 00002389 90992589 Wea 00 00 2359 00002558 00002359 Sat 00 00 2359 00002359 9099 2389 M enu 21 H oliday date E E T E ___ _ LLLI E 1921522 REEL ___ _ L9 LE LLL
62. an Contactor 15 Condenser Fan Contactor 15 m m o Condenser Fan Contactor M 22 m Condenser Fan Contactor M 23 m o Condenser Fan Contactor M 22 Condenser Fan Contactor M 23 m m co Condenser Fan Contactor M 24 m Condenser Fan Contactor M 24 m Condenser Fan Contactor 25 Compr 3 Contactor m Condenser Fan Contactor 25 Compr 3 Contactor e Compr 3 Top Solenoid Valve feed Compr 3 Top Solenoid Valve feed Compr 3 Bottom Right Solenoid Valve feed Compr 3 Bottom Left Solenoid Valve vent Compr 3 Bottom Right Solenoid Valve feed Compr 3 Bottom Left Solenoid Valve vent A Condenser Fan Contactor M 32 gt Condenser Fan Contactor M 32 Condenser Fan Contactor 33 o Condenser Fan Contactor M 34 Condenser Fan Contactor 33 Condenser Fan Contactor M 34 o Condenser Fan Contactor 35 Condenser Fan Contactor M 35 Hot Gas Bypass SV5 Hot Gas Bypass SV6 IM 549 Hot Gas Bypass 575 Hot Gas Bypass SV6 Not Used Compr Contactor Compr Top Solenoid Valve feed Compr Bottom Right Solenoid Valve feed Compr Bottom Left Solenoid Valve vent Condenser Fan Contactor M 42 Condenser Fan C
63. ater and refrigerant piping details All operating descriptions con tained in this manual are based on MicroTech controller software version SC2 X18B SC 3XX19 and SC4XX19A Chiller operating characteristics and menu selections may vary with otherversions of controllersoftware Contact M cQuayService for software update information A CAUTION This equipment generates uses and can radiate radio frequency energy and if notinstalled and used in accor dance with the instructions manual may cause interfer ence to radio communications It has been tested and found to comply with the limits for a class A digital device pursuant to part 15 of the FCC rules These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense McQuay International disclaims any li ability resulting from any interference or for the correc tion thereof General D escription The MicroTech Unit Control Panel available on all McQuay ALS and PFS products contains a Model 250 Microproces sor based controller which provides all monitoring and control functions required for the safe efficient operation of the unit The operatorcan monitoralloperating conditions by using the panel s built in 2 line by 16 char
64. ature Circuit 2 Suction Temperature Circuit 2 Liquid Line Temperature Circuit 1 Liquid Line Temperature Circuit 1 Liquid Line Temperature Circuit 2 Liquid Line Temperature Circuit 2 Low Pressure Transducer Circuit 3 Low Pressure Transducer Circuit 3 High Pressure Transducer Circuit 3 High Pressure Transducer Circuit 3 Suction Temperature Circuit 3 Suction Temperature Circuit 3 Liquid Line Temperature Circuit 3 Liquid Line Temperature Circuit 3 Discharge Temperature Circuit 1 Low Pressure Transducer Circuit 4 Discharge Temperature Circuit 2 High Pressure Transducer Circuit 4 Discharge Temperature Circuit 3 Suction Temperature Circuit 4 Percent Circuit Amps Circuit 3 Liquid Line Temperature Circuit 4 13 Sensor Locations 3 Screw Compressor U nit 519 S16 S16 17 13 COMPR 3 COMPR 2 Inside Control Box on Power amp Control Panels 5105 SIL 823 One Sensor For Each Circuit 09 COMPR 1 819 821 512 501 500 508 503 520 Sensor Locations 4 Screw Compressor Unit COMPR 1 COMPR 3 S11XS10 COMPR 2 14 IM 549 Digital Inputs Note All digital inputs are 24 At 7 5 VAC to 24 VAC the digital input contacts are Below 7 5 VAC the contacts are considered open and considered closed and the signal level is high the signal le
65. axPullon 01100005 ResetO pt None ResetS xx xma 9 MaxChWRst xx x F C 10 0 0 1 1 0 0 0 45 0 0 0 10 0 90 0 32 2 90 2 Not Changeable 0 0 45 0 0 0 25 0 Return 4 40 Ma Network Ice Outdoor ______________________ 10 0 55 OatMaxRste xxx F 60 0 15 5 0 0 90 0 17 8132 2 HiChWTmp xxx x F C 60 0 15 5 20 0 90 0 6 6 32 2 Note indicates Centigrade values minus sign is not displayed with three digit numbers 40 IM 549 M enu 14b Lvgevap spts valuesfor 134a refrigerant Screen Factory Set Point Lug T C MaxPullDn x x F C O 2 1 e hl 5 6 ResetO pt None Return 7 4 40 Ma Network Ice Outdoor 8 92 2 dn se Ce 0 MaxChWRsteic RetumSpt c EC 12 13 15 5 2 15 0 0 90 0 6 6 32 2 10 11 HiChWTmp xxx x F 60 0 Note indicates Centigrade values the minus sign is not displayed with three digit numbers M enu 15 Soft load spts Display Timeleft xmin y M enu 16 Compressor spt M enu 17a H ead presspt valuesfor R 22 refrigerant StageDnErr xxx 100 690 50 400 340 2760 Notes indicates Centigrade values M enu 17b H ead presspt valuesfor 134a refrigerant D isplay F
66. d EXV or low refrigerant charge If the pre purge is successful but the evaporator pressure does not rise after the electronic expansion valve is com manded to open the circuit will be shut down Failed low ambient start The circuit will be shut down if the controller records an unsuccessful low ambient start Can t pump down elapse timer 180 seconds is started whenever the controller initiates a pumpdown sequence If the circuit is still attempting to pump down when the timer expires the compressor is stopped and the alarm output is activated The display reads Can t Pump Down Bad evaporator pressure sensor A shorted oropen evaporator pressure sensor will shutdown the refrigerant circuit and activate the alarm output Bad condenser pressure sensor shorted or open condenser pressure sensor will shut down the refrigerant circuit and activate the alarm output Wait flooded Suction superheat is less than 3 F and compressor will not start Wail flooded xxx Liquid presence sensor detected liquid in the compressor xxx indicates time in minutes before unit will start after liquid clears from the compressor IM 549 icroTech Controller Test Procedures CAUTION Service test mode should only be used by Mc QuayService personnel or other factory trained tech nicians The following test procedures will disable all normal chiller controls and safeties All compressors MUST be disabled by
67. dT rol UnitCapacity 5580 Stel 60 120 100 Stages Sei Ser Ser A0 25 20 30 120 70 50 30 25 20 20 60 50 30 20 15 15 15 10 10 10 10 50 30 20 Table 110 D eadband T able W ith SpeedT rol UnitCapacity StageO Stagel 40 40 40 Ser 556 40 25 20 30 40 40 40 30 25 20 20 70 30 30 20 15 15 15 80 30 20 IM 549 10 10 10 10 25 Condenser Fan Stage Up Every four seconds the controller records the difference between the maximum condenser pressure as defined by the minimum lift plus the dead band and the actual con denser refrigerant pressure This value is added to the previously recorded values and when the accumulated total H igh Pressure Stage U p The controller logic will bring on multiple condenser fan Condenser Fan Stage D own Every four seconds the controller records the difference between the minimum condenser pressure and the actual condenser refrigerant pressure This value is added to the previously recorded values and when the accumulated total is equal to or greater than the stage down set point the SpeedTrol Logic When the SpeedTrol option is installed the MicroTech con troller will generate an analog signal via the AOX board to directly control the S66DC 1 variable speed fan motor con trol The control signal is proportional to the condenser pressure s relative position within the lift press
68. denser water nozzle Percent Unit Amps Signal converter board Suction Temperature Circuit 1 Well brazed to the cir 1 suction line Suction Temperature Circuit 2 Well brazed to the cir 2 suction line Liquid Line Temperature Circuit 1 Well brazed to the cir 1 liquid line Liquid Line Temperature Circuit 2 Table 4b Analoginputs 3 compressor units Evaporator Leaving Water Temperature Well brazed to the cir 1 liquid line Table4c Analoginputs 4 compresor units Evaporator Leaving Water Temperature Low Pressure Transducer Circuit 1 Low Pressure Transducer Circuit 1 Low Pressure Transducer Circuit 2 Low Pressure Transducer Circuit 2 High Pressure Transducer Circuit 1 High Pressure Transducer Circuit 1 High Pressure Transducer Circuit 2 High Pressure Transducer Circuit 2 Evaporator Water Temperature Reset Field Supplied Evaporator Water Temperature Reset Field Supplied Demand Limit Field Supplied Demand Limit Field Supplied Evaporator Entering Water Temperature Evaporator Entering Water Temperature Outside Air Temperature Outside Air Temperature Percent Circuit Amps Circuit 1 Percent Circuit Amps Circuit 1 amp 3 Percent Circuit Amps Circuit 2 Percent Circuit Amps Circuit 2 amp 4 Suction Temperature Circuit 1 Suction Temperature Circuit 1 Suction Temper
69. e O utput Field Wiring ALS 125A 204A 717449 01 704352C 01 716995D 01 716996D 01 716997D 01 719740C 01 PFS 140A 200A 719836 01 719833C 01 716998D 01 716999D 01 718099D 01 719835C 01 ALS 205A 280A 717460 01 704352C 01 718507D 01 718508D 01 718509D 01 719740C 01 ALS 300A 380A 719869 01 718640D 01 718641D 01 718642F 01 719740C 01 Control Cabinet Layout ALS 125A 204A FB FB FB FB FB Keypad 6 7 8 9 1110 11 5 T1 GRD Mech relays F1CBF2 E NB fd 11 12 13 15 23 M25 GFP S ADX EXV High voltage wireway M21 M22 14 M24 Low voltage wireway GFP B R 5 2 E MDBI ADI Output board 8 os 011 OL2 016 9 1 9 B Low voltage wireway 5 CBS CB2 TB4 TB5 9 Low voltage wireway Low voltage wireway 1 E T4 T2 0119 9 8 8 17 i Fax alarm C1 C2 option M5 M1 M2 M6 2 KE
70. e controller before dis Troubleshooting Analog Inputs Ananalog input such as a temperature sensor is connected to the Analog Input terminal strip on the ADI board The analog input is then conditioned by the ADI board The conditioned input is transferred to the MCB via a ribbon cable Analog input not read by the M CB Ifthe MCB appearsto befunctioning properly and the analog input is not being read by the MCB perform the following procedure 1 Try cycling power to the controller by opening and then Troubleshooting D igital Inputs A digital input device is connected to the Digital Input terminal strip on the Input Conditioning Module Terminal Board 24 Vac supplied by the CSC is sent to the digital input device via a supply wire When a contact in the digital device makes a return signal is sent back to the Digital Input terminal strip The signal is then conditioned by the Input Conditioning Module ICM The conditioned digital input is then sent to the MCB via a ribbon cable Digital input not read by the MCB Ifthe MCB appears to be functioning properly and the digital input is not being read by the MCB perform the following procedure Troubleshooting Analog O utputs Variable voltage or current control signals are sent to analog outputs by the MCB through the Analog Output Expansion Module AOX 4 This can be on the ALS units as the optional fan speed control The MCB sends a voltage or current signal to the AO
71. e timer for stage down commands is of the stage up timer anti cycle timers are 5 minutes stop to start and 15 minutes start to start 3 F the heater will be energized The heater will be de energized when the superheat rises above 8 F 21 Lead Lag of Refrigerant Circuits The following compressor control rules are enforced in the control software The MicroTech controller will never turn on the lag com pressor until the lead compressor is at 7596 capacity or greater and additional cooling capacity is required Automatic Lead L ag The controller provides automatic lead lag of refrigeration circuits based on compressoroperating hours and the num ber of starts The circuit with the fewest number of starts will M anual Lead Lag The operator may override automatic circuit selection by manually selecting the lead circuit via the keypad When the set point equals auto the lead compressor is selected by the MicroTech controller based upon which Electronic Expansion Valve O verview McQuayscrew compressorchillers are supplied with S porlan SE series electronic expansion valves The MicroTech con troller generates valve positioning signals to maintain refrig erant circuit superheat to within 1 5 F of the superheat set point Valve positioning signals are converted to actuator EXV Superheat Control The electronic expansion valve position will be adjusted to maintain the refrigerant circuit s superheat set
72. enser Refrigerant Pressure Circuit 1 2 3 amp 4 Saturated Suction Temperature Circuit 1 2 3 amp 4 O ptional Sensor Packages Water cooled units only Entering Condenser Water Temperature Leaving Condenser Water Temperature T hermistor Sensors MicroTech panels use a negative temperature coefficient thermistor for temperature sensing A normal sensor will measure 3000 ohms at 77 F IM 549 Liquid Line Temperature Circuit 1 2 3 amp 4 Provides direct display of subcooling and superheat Entering Evaporator Water Temperature Ambient O A Temperature Air and water cooled units Percent Unit Amps on 2 Compressor Units Percent total unit amperage including compressors and condenserfans Does notinclude externally powered equip ment such as water pumps Percent Compressor Amps On 3 Compressor Units And Percent Circuit Amps 1 amp 3 2 amp 4 On 4 Compressor Units Figure8 T hermistor sensor Stainless steel tubing Shielded 2 cable oV AT 2 EE E 222 27272 Potting Thermistor Table2 M icroT ech thermistors 10 IM 549 Pressure Transducers These transducers are selected for a specific operating range and provide an output signal which is proportional to the sensed pre
73. er supply terminals Power fuses Bussman GDC T2A Fuse F1 Fuse F2 Power in 18 24 VCT AC AC GND GND AUX OUT A The best way to accomplish these checks is to perform the start up procedures as specified in the Network Com missioning section of the appropriate IM manual If these procedures have performed and the problem persists obtain factory service out To check for the 5 Vdc on the IDC connector pull back the plug aboutone eighth of an inch and placethe test leads against the exposed pins If there is no voltage the MCB is probably defective Display is blank or garbled Ifthe MCB appearsto befunctioning properly and the display is completely blank or garbled perform the following proce dure 1 Try cycling power to the controller by opening and then closing circuit breaker 2 Try adjusting the contrast trim pot which is located on the back ofthe keypad display assembly If the contrast trim pothas no effect itis likely that eitherthe keypad display or its ribbon cable is defective 3 After removing power from the controller check the ribbon cable and connections between the keypad dis play and the MCB Lookforbentpins Restore power after reconnecting the ribbon cable 31 4 Try swapping a known good ribbon cable and keypad display Swap these components separately to isolate the problem Remove power from th
74. ered to be system alarms On a system alarm the MicroTech controller will shut down both com pressors and energize the alarm output Loss of C hw flow On aloss ofchilled waterflow forthree consecutive seconds while the chiller is in cooling mode all operating refrigerant circuits will pump down and stop The display will read Loss of ChW Flow When chilled water flow resumes the chiller will initiate a normal start sequence Bad phase voltage The factory mounted voltage protection device will signalthe MicroTech controller if the incoming 3 phase power is not within acceptable limits The controller will immediately shut the chiller down When the voltage protection device indi Circuit Alarms Alarm conditions which are unique to each refrigerant circuit are considered to be circuit alarms On a circuit alarm the MicroTech controller will shut down the affected circuit s compressor and energize the alarm output M echanical high pressure Closure of the HP1 or HP2 relay contacts indicates an abnormally high compressor discharge pressure The latch ing mechanical high pressure switch must be reset before the MicroTech alarm can be cleared The mechanical high pressure switches should be set to trip at the following pressures ALS Units 400 psi PFS Units 380 psi IM 549 evaporator pressure falls below the Stop Pumpdown Pres sure set point An additional pumpdown sequence can be performed by moving the pu
75. erefore it is possible to download the proper controller software to a replacement MCB at the building site if a PC equipped with that job s Monitor software is available In addition if the controller s configuration data was stored on the PC hard drive prior to the MCB failure the exact configuration data including all keypad programmable set points and parameters can be restored Referto the user s manual supplied with the Moni tor software for more information IM 549 Connecting the C ommunications Trunk Use the following three procedures to connect the chiller controllers to the network Communications cable check The network communications cable should have been in stalled in accordance with the instructions in the Field Wiring section ofthis manual This procedure will verify that there are no shorts orstray voltages anywhere inthe commu nications trunk Before beginning verify that the port B connectors are disconnected from every controller on the trunk 1 Verify that there is voltage between any conductor and ground Use a voltmeter to test for voltage at the field wiring terminal block or directly on the port B connector of the level 1 controller With one lead on the control panel chassis ground check for voltage at the and ground terminals There should be no AC orDC voltage see the Signal and Terminal columns of Table 3 If the conductors are properly terminated this check will
76. eshooting O utput Boards Each output on the Output Board consists of a solid state relay a LED 5 amp fuse and an MOV metal oxide varistor Normally when the MCB commands an output to ener gize the solid state relay contacts will close and the LED will glow The contacts of each solid state relay are in series with a 5 amp fuse These fuses resemble small resistors and are located on the board adjacent to the relays they serve The fuses are pressed into place They can be removed with a needle nose pliers The MOV which is located on the under side of the output board protects the solid state relay from high transient voltages 5 part of the output board and cannot be replaced Following are troubleshooting procedures for various symptoms of output board problems Note It should be possible to determine whether a solid state relay is defective by using these procedures However if you need more information on troubleshooting them refer to Troubleshooting Solid State relays below Figure 16 Output board rday sock amp Van 250V 50 60 Hz 120V 50 60 Hz Test resistor a 330 680 Ohm A WARNING Electric shock hazard Can cause severe injury or death Even when powerto the panelis off solid state relay socket terminals 1 and 2 on the output board could be connected to high voltage see Figure 5 Avoid them OneLED out If one of the Output B
77. formation on the MicroTech operating conditions and the chiller oper ating conditions The entries under each menu item in this Control Category Menus and menu items in this category provide forthe input of all the unit control parameters These include cooling control compressor control and IM 549 mode is turned off Manually operating outputs 1 and 2 will drive the electronic expansion valve open or closed Com pressor MCR outputs 4 and 8 will only remain in the on state for 15 seconds Exit the Service Testing mode by selecting the desired chiller operating mode from menu 13 Press the Next item key to select test 17 DH2 The current state of the second 8 digital inputs 8 15 will be represented on the keypad display as a row of ones orzeros where 1 equals on and 0 equals off By manipulating field wired devices flow switch remote stop switch etc and watching the keypad display the status of the second eight digital inputs can be verified Exit the Service Testing mode by selecting the desired chiller operating mode from menu 13 tree structure STATUS CONTROL and ALARM Each cat egory is divided into Menus and each menu into Menu Items The three categories are described below category provide information only and are not changeable through the MicroTech keypad condenserfan control parameters as wellas time schedules and alarm limits The entries under these menu items are changeable through the Micro
78. former option seu CH Disconnect by others ARI 10A use 120 VAC 1 7 Fe control power B others 1 If separate evaporator heater 545 power option is used Disconnect i 540 remove wires 540 and 545 Separate by others Use evaporator 120 VAC WW Ee BEES heater power others ilis th 5 OR option TEE AH EPOR 16 24V or 120 VAC byothers Te 18 9 Solid state relay ZE 24V or 120 N e 1 5 amps max CHW pump relay L 5A by others LAN TB4 4 20 E 49 CAW reset 45 i Ee by others 4 4 iby JO E Bi Inherent in I MicroTech 7 20 SF GND controller DI 3 4 4 demand et W 48 i 250 load __ by others impedance ease oes 4 1 18 85232 TR Connection to RS232 50 Communication for modem or direct 4 8 3 BLK RS232 RC port A PC connection 4 8 5 GND GND 2 52 Connection to RMS 4 3 BLK 85485 remote monitoring sequence ommunication to NMP CH 4 CLR RS485 port B network master panel Q PINE 48 4 5 080 GND f Time Off clock Aito Remote stop Pig ag th an 4 Bea If remote stop control is used remove jumper CL from terminals 60 to 61 Manual
79. is typically used during morning start up When the controller M ax Pull Down The controller can limit the rate at which the chilled water loop temperature is reduced Whenever the rate of tempera Condenser Fan C ontrol Condenser Fan Staging The first condenserfan staging will be started in conjunction with the first compressor to provide initial head pressure control The MicroTech controller continuously monitors the lift pressure referenced to several head pressure control set points and will adjust the number of operating condenser H ead Pressure Control Air Cooled Units O nly For each circuit the first stage of condenser fans will be wired in parallel with the compressor output so thatthey are energized with the compressor For chillers with optional SpeedTrol the first condenserfan stage will receive a control signal from the AOX board which in turn modulates the Johnson Controls S66DC 1 to provide variable speed fan operation Each circuit has 3 additional digital outputs avail able for refrigerant head pressure control Each output will energize an additional bank of condenser fans with each bank consisting of 1 or 2 fans depending on the size of the unit Each output energizes additional heat rejection due to increased air flow across the air cooled condenser regard 24 made to the leaving chilled water set point The corrected leaving water set pointis neversetto a value greaterthan the return water set point and is
80. k the position of the front panel System Switch S1 If the switch is in the stop position the chiller will remain off and the display will indicate the operating mode to be OFF SystemSw The controller will then check the PumpDown Switches If any switch is in the stop position that circuit s operating mode will be displayed as OFF RemoteComm if this operating Start up If none of the above Off conditions are true the MicroTech controller will initiate a start sequence and energize the chilled water pump output relay The display will indicate Starting as the operating mode The chiller will remain in the Waiting For Flow mode until the field installed flow switch Waiting for Load Once flow is established the controller will sample the chilled water temperature and compare the Leaving Chilled Water Set point the Control Band and the Load Delay which have been programmed into the controller s memory If the leaving chilled water temperature is above the Leaving Start Requested Inthe Start Requested Mode the electronic expansion valve is assumed to be fully closed The MicroTech controller will read the evaporator pressure to ensure at least 4 psi of Prepurge In orderto purge compressor of any liquid refrigerant that may be present the lead compressor is operated at 50 capacity while the electronic expansion valve is held fully closed The refrigerant circuit will continue to run in this mode
81. lled Water Freeze 27 Bad Leaving Chilled Water Sensor 27 8 ete ie aan 27 Mechanical High 27 High Condenser 27 High Condenser Pressure Stage Down 27 High Condenser Pressure Stage Hold 28 No Liquid Start ioo ens 28 Ne Liquid RUN iocos poete qute t 28 Can t Start Low Evaporator Pressure 28 Low Evaporator Pressure 28 Freeze Protect Stage Down and Freeze Stat Protect 28 Failed Pre Purge se 28 Failed EXV or Low Refrigerant Charge 28 Failed Low Ambient Start 28 Cant i 28 Bad Evaporator Pressure 28 Bad Condenser Pressure 28 Wait Flooded inte eripe 28 Wail Elooded teet testet 28 MicroT ech Controller T est Procedures 29 Service Test Digital 29 Service Test Digital 29 IM 549 Keypad D isplay 29 IR ER IAM A 29 Te ele EE 29 Control Category coeno teet 29 dede
82. ls on the Output Board should not be less than 3000 ohms Ifthe componentresistances are proper check the resistance of the field supplied loads if any and check the wiring and connections throughout the 5 Vdc power supply circuit Disconnect connector plugs from the modem and the power plug from all AOX 4 boards as applicable With circuit breaker CB1 open measure the resistance be tween field terminals DC GRD and 13 Vdc It should be infinite If the resistance is infinite go to step 12 If the resistance is not infinite a short exists some where in the 13 Vdc power supply wiring Reconnect the Aux Out connector plug to the MCB If there s amodem reconnectits AMP plug to portA With 1 1 Troubleshooting C ommunications Problems If a communications problem occurs check the following items Check the port B voltages Check the port B fuses Check the network integrity Check the network addressing Troubleshooting the K eypad D isplay Interface Keypad Display Interface is connected to the MCB a ribbon cable and discrete wiring forthe back light The MCB provides operating voltages control signal outputs for the display and input conditioning for the keypad inputs Display is hard to read The clarity of the LCD display can be affected by ambient temperature Typically less contrast will result with cooler temperatures If the display is difficult to read adj
83. mber of starts as the lead circuit and initiate the compressor start sequence refrigerant pressure is present If the evaporator pressure is less than 4 psi the compressor will not be enabled and the display will read NoStart LoEvap to less than 40 psi or 45 seconds has elapsed If the evaporator pressure does not drop to 40 psi within the 45 seconds the compressor will stop and the display will read Failed Prepurge The alarm output will be activated 19 O pened EXV With the evaporator pressure less than 40 psi and the compressor still running the electronic expansion valve will be driven open to 200 steps If the evaporator pressure rises above the freeze stat set point the chiller will advance to Low Ambient Start If the difference between the freeze stat set point and the evaporatorrefrigerant pressureis greaterthan 12 psi the low ambient start timer will be setto 180 seconds The compres sor will continue to run for 180 seconds from the momentthe expansion valve is opened in an attempt to build up the evaporator pressure If the difference between the freeze stat set point and the evaporator refrigerant pressure is greater than 12 psi the following calculation will be used to set the low ambient start timer Cool Stage Circuit capacity at initial start will be 5096 Once the chiller has started the MicroTech controller will add or subtract cooling capacity to maintain the chilled water set point The cu
84. mpdown switch to the Auto position for ap proximately 3 seconds and then back to the Stop position If the evaporator pressure is above the Begin Pumpdown Pressure set point the controller will initiate a pumpdown sequence and the compressor will stop when the evaporator pressure falls below the StopP umpdownP ressure Set point cannot be obtained the compressor will stop after 300 seconds have elapsed The set point will be set to No automatically at the end of the cycle Note All pumpdown modes are disabled if the system switch S1 is in the Stop position N ote Compressorcapacity during apumpdown sequence will be 50 cates that the incoming power is back within acceptable limits normal chiller operation will resume No5VDC AI The controller continuously monitors the output of both internal 5VDC powersupplies and calculates their ratio If the microprocessor is not receiving an acceptable volts ratio signal the unit will be shut down The voltage present at analog input 5 must be between 4 15 and 4 94 VDC Chilled water freeze protect If the leaving chilled water temperature falls below the adjustable freeze H20 set point the unit will be shut down Bad leaving chilled water sensor If the MicroTech controller detects an open or shorted leaving water sensor the chiller will be shut down H igh condenser pressure If the condenser pressure as sensed by the pressure trans ducer exceeds the high conden
85. multi conductor cables or discrete wiring Power for the system is provided by transformers T 2 and 4 field wiring must enter the control cabinet through the Figure 1 T ypical control cabinet layout 2 compresor unit knockouts provided and be terminated on field wiring termi nalstrips The standard ALS keypad display is located inside the control cabinet protection from the weather while the PFS Keypad Display is accessiblethrough the exterior ofthe control cabinet See Figure 1 fortypical control cabinet layout FB7 ep FBS n GRD 22 M13 m15 M23 M25 110 GFP 5 M21 Gei GFP R 0L5 011 012 016 CB5 82 86 2 5 M1 a M2 M6 Keypad Mech relays 11108 F2 ve EXV High voltage wireway Low voltage wireway Mpa ADI Output 5 board 5 5 5 v 8 9 P Low voltage wireway 9 TB4 5 TB5 8 Low voltage wireway Low voltage wireway r 1 a 8 T4 T2
86. never set a value less than the actual leaving chilled water set point stages while a 20mA signal will allow only 1 stage to operate The effect of the reset signal may be calculated by using Figure 13 limit signal from the network master panel in the range of 096 to 10096 with 0 equaling no limit enters the Cool Staging mode of operation the controller will starta count down timerto indicate how long the unithas been in the cool staging mode The maximum number of cooling stages will be limited to the soft load set point until the soft load count down timer equals zero ture decrease exceeds the maximum pull down set point no additional cooling stages will be activated fans as required to maintain proper head pressure For PFS water cooled units the condenser pump will be started in conjunction with the first compressor to provide head pressure control less of the number of fans If the outdoor ambient tempera ture is greater than 60 F when the unit is started one additional condenser fan stage will be energized If the outdoor ambient temperature is greater than 80 F two additional fan stages will be energized ALS unit EERs are maximized by not allowing the last condenser fan stage to operate when the unit capacity is 25 and the condenser pressure is below 200 psi The last fan stage will operate if the condenser pressure is above 220 psi at 25 unit capacity IM 549 Lift Pressure C alculation The minimum
87. ntroller by opening and then closing circuit breaker CB1 2 Check the ribbon cable power wiring connector and the field wiring connections from the digital input device Look for bent pins cable on backwards or miswires Restore power after reconnecting all cables and wires 3 Ifthe problem persists try swapping aknown good ribbon cable an ADI board ora digital input device Swap these components separately to isolate the problem Remove power from the controller before disconnecting the sus pect component and restore power after connecting the replacement component If the problem persists it is likely that the MCB is defective AOX 4 to the analog output device and the power wiring from the external power supply to the output device Look for bent pins cable on backwards or miswires Restore power after reconnecting all cables and wires Note If the analog output signal supplied by the MCB is a voltage signal 0 5 0 10 Vdc the external power supply ground must be grounded to the MCB chassis ground 3 Ifthe problem persists try swapping a known good AOX 4 ribbon cable s analog output device orexternal power supply Swap these components separately to isolate the problem Remove power from the controller and analog output device before disconnecting the suspect compo nent and restore power after connecting the replacement component If the problem persists it is likely that the MCB is defective IM 549 Troubl
88. nu item pressing CLEAR returns the display to the original value as long as ENTER has not yet been pressed Note The cause of an alarm should always be determined and corrected before clearing the alarm through the keypad Example of keypad operation As an example of using the keypad key functions consider reprogramming the Leaving Evaporator Set point from 44 F to 42 F This consists of changing the menu item 14A Leaving Evaporator Set point entry from 44 F to 42 F Assume menu 1 Unit Status is currently in the display The following key sequence is followed 1 Press the CATEGORY group CONTROL key onetime This switches the display to menu 13 the first menu in the CONTROL category 2 Press the group NEXT key once This shifts the display to menu item 14 Leaving Evaporator Set point 3 Press the ACTION group DEC key one time This prompts the user to enter the password Enter Enter Enter Enter 4 Afterthe Password Verified message press the ACTION group DEC key four times This changes the menu item entry to 42 F 5 Press the ACTION group ENTER key one time This stores the new entry into the MicroTech controller memory 6 Pressing the CATEGORY group STATUS key then shifts the display back to menu 1 f Bus mouse or trackball g Hard Disk Drive 120 Megabyte min A mass data storage area for the operator interface
89. numbers and names along with their corresponding menu items and menu item entries as they appear on the MicroTech display The symbol is used where the controller would normally display a numerical value Also included in this figure is the corresponding switch menu for each menu item Notes 1 Status Category Where more than one menu item entry is listed undera menu item the list includes all the entries which can appearin the display forthe particular item The entry that shows in the display depends on the operating status of the unit 2 Control Category Where more than one menu item entry is listed undera menu item the list includes allthe choices from which the user can select The selected entry ap pears in the display 3 Alarm Category The entries listed include all the pos sible alarm messages The display reads the alarm condi tions which occur 38 noted however that for maximum convenience and func tionality the computer should be considered a dedicated computer for the MicroTech system The communications cable from the unit control panel to the personal computer is shielded twisted pair wire Belden 8761 or equal The communications adheres to the indus try standards of RS 232C and the rate of communications is 9600 baud The recommended maximum distance from the personal computer to the control panel is 50 feet If the required distance is in excess of 50 feet an optional RS 232 extension kit i
90. nus throughout the menu tree structure This reduces the need to step through all the menus one by one in order to reach the desired menu A STATUS Pressing the STATUS key at any time shifts the display to Menu 1 Unit Status which is the first menu of the STATUS category B CONTROL Pressing the CONTROL key at any time shifts the display to Menu 13 Control M ode which is the first menu of the CONTROL category C ALARM S Pressing the ALARMS key atany time shifts the display to Menu 24 Circ 1 Current Alarm which is the first menu of the ALARMS category D SWITCH Pressing the SWITCH key at any time toggles the display between the current menu status control item and the related menu control status item somewhere else in the tree structure For example if this key is pressed while the current menu item is menu item 4A Leaving Evaporator the display shifts to menu item 14A Leaving Evaporator Set point This provides for easy review of actual versus set point values IM 549 Menu group The keys in this group are for stepping from menu to menu in the menu tree structure A PREV Pressing PREV shifts the display to the previous menu Note When Menu 1 is currently in the display the first menu in the menu tree structure press ing PREV causes an end of menus message to appearin the display Pressing PREV again causes the display to wrap around to Menu 27 the la
91. oard LEDs fails to illuminate when the MCB is commanding the associated output to energize perform the following procedure 1 Remove powerfromthe controllerby opening CB1 Swap the suspect relay with a known good relay Try to choose arelay that will notaffect unitoperation Restore powerby closing CB1 If the LED does not light go to step 2 If the LED lights the suspect relay is defective 2 Remove power from the controller Check the ribbon cable and connections between the OB and the MCB Look for bent pins If the cable and connections are intact go to step 3 3 Remove the relay from the suspect socket Install a 330 680 ohm resistor between terminals 3 and 5 as shown in IM 549 Figure 5 Restore power by placing CB1 to the ON position The LED should lightregardless ofthe controller s command Ifthe output LED illuminates itis likely that the M CB is defective Ifthe output LED does notilluminate the output board is defective All LEDs out If the MCB is commanding at least two outputs to energize and none of the Output Board LEDs are lit perform the following procedure 1 Verify that 5 Vdc is present at the Output Board s power terminals If 5 Vdc is not present go to step 2 If5 is present check the ribbon cable and connec tions between the output board and MCB Look for bent pins If the cable and connections are intact the Output Board orthe MCB is defective 2 Remove power from the contr
92. of these may be defective 8 Reconnect the digital output ribbon cable to the MCB Cycle power to the controller and check the power fuses If both fuses are intact go to step 9 If either fuse blows check Output Board and the connecting ribbon cable Either of these may be defective IM 549 9 If there are any AOX 4 boards reconnect the expansion bus ribbon cable to the MCB otherwise go to step 10 Cycle power to the controller and check the power fuses If both fuses are intact go to step 10 If either fuse blows check the analog output expanion modules if any the connecting ribbon cables and the field wiring for shorts Any of these may be defective 10 With circuit breaker CB1 open measure the resistance between field terminals DC GRD and 5 Vdc It should be greater than 20 ohms Ifthe resistance is greater than 20 ohms go to step 11 if the controlleris equipped with least one AOX 4 board or a modem Otherwise the problem is indeterminate Obtain factory service Ifthe resistance is less than 20 ohms itis likely thatthe keypad display the Output Board or an external field supplied load is excessively loading the MCB s 5 Vdc power supply Isolate the problem by taking resistance measurements on each of these devices with the wiring disconnected The resistance across the power input terminals on the keypad display G and 5V should be close to infinite The resistance across the power input termina
93. oller by placing CB1 to the OFF position Disconnectatleastone wire from the power inputterminals ofthe Output Board The resistance should not be less than 3000 ohms If the resistance is greater than the acceptable value go to step 3 If the resistance is less than the acceptable value the Output Board is defective LED lit output not energized Ifthe LED of a suspectis lit but load connected to itis not energized and everything is intact between the MCB andthe coil side of the relay perform the following procedure to isolate the problem 1 Verify that 24 or 120 Vac power is present at the suspect output s screw terminal on the Output Board 2 Remove power from the controller by placing CB1 Swap the suspect relay with a known good relay Try to choose relay that will not affect unit operation Restore power by closing CB1 If the output load energizes the suspect relay is bad Replace the relay If the output load does not energize when LED is lit again check the load circuit wiring and components Output energized LED not lit If the LED of a suspectis not lit but the load connected to it is energized either the solid state relay or the MOV is bad The solid state relay contacts and the MOV which are in parallel can both fail closed Perform the following proce dure to isolate the problem 1 Remove power from the controller by opening CB1 Pull the solid state relay from the suspect output s socket 2
94. ontactor M 42 Condenser Fan Contactor M 42 Condenser Fan Contactor M 42 w LA LA WW e LA o LA 17 Installation Controller Calibration The control software is installed and tested by the factory prior to shipping therefore no periodic calibration of the controller is required All control and safety set points will be checked and adjusted if necessary by the McQuayService Field Wiring Analog sensors and transducers All sensors and transducers required for normal chiller op eration are installed and wired by the factory Any optional analog signals provided by the installing contractor require twisted shielded pair wire Belden 8760 or equal Digital input signals Remote contacts for all digital inputs such as the chilled water flow switch and the remote start stop switch must be dry contacts suitable for the 24 VAC control signals pro duced by the screw chiller control panel Digital outputs Devices wired to the digital outputs typically be an optional Chilled Water Pump control relay or an Alarm Annunciator The MicroTech output device is a normally open solid state relay with an on board replaceable 5 amp fuse The model 250 controller activates a solid state relay by sending a trigger signal to the output board via the attached ribbon cable The relay responds to the trigger by lowering it s resistance which allows curren
95. ooler heating tape and control circuit transformer may be supplied as options on some installations Wiring forthese circuits is to be provided by the installing contractor and should conform to the Na tional Electrical Code and all applicable local building codes Power supplies There are several internal power supplies used by the con troller and its associated circuitry The regulated 5 VDC power on terminal 42 is used to support the analog inputs on the ADI Board and should not be used to operate any external devices An unregulated 12 VDC power supply is available on field wiring terminal 456 and an unregulated 24 VAC supply is provided at terminal 81 Both ofthese may be used for powering external devices such as low current relays and lights D emand limit and chilled water reset signals Separate 4 20 milliamp signals for remote chilled water reset and demand limit can be provided by the customer and should be connected to the appropriate terminals on the field wiring strip inside the control cabinet The optional demand limit and chilled water reset signals are 4 to 20 milliamp DC signals The resistive load used to condition the milliamp input signals is a 249 ohm resistor factory mounted on the ADI Board Communication ports Communication port A is provided on the MicroTech con troller for connection to an IBM compatible computer for local or remote system monitoring Belden 8762 or equiva lent The network uses the 5232
96. ort N A F 3 0 0 s 6 Cond Fan Stage x M enu 11 Circ 1 temp s M r Satur Evap xxx F C N A C SuctLine xxx x F Open F re Short F C eee Satur SC N A F C Liquid Ln xxx x F C N A F 2 eC Open F sa Short F C M enu 12 Circ 2 temp s Satur Evap xxx F C N A F C SuctLine xxx x F Open F Short F C Super Ht xxx x F C N A F C Satur Cond xxx F C N A F C Liquid Ln xxx x F C N A F C SR XXX X F N A F C Dscharge xxx x F Open F C Short F C IM 549 M enu 13 Circ 3 temp s Satur Evap xxx F C N A C xxx x F Short F C Super Ht xxx x F C N A F Liquid Ln xxx x F C N A F C SubC oolg xxx x F N A F C Dscharge xxx x F C Open F Short F C Satur Evap xxx F C N A C xxx x F C Short F C Super Ht xxx x F C N A F Satur Cond xxx F N A Liquid Ln xxx x F C N A F C SubCoolgz xxx x F C N A F C Dscharge2oo x F C Open
97. p 145 psi kPa F Open N A F Short N A F C Cond xxx x psi kP a Cond 450 psi kPa Open N A F C Short N A zt MmcodPr 0 4 a 0 PS PwPostion xw 6 conifansme x IM 549 M enu 9 Circ 1 temp s Satur Evap xxx F C N A F SuctLine xxx x F Short F C Super Ht xxx x F C N A F 22 XXX X F N A SubC XXX X F N A F Open F Short F C M enu 10 Circ 2 temp s Satur Evap xxx F C N A F C SuctLine xxx x F Short F C Super Ht xxx x F C N A F C Satur Cond xxx F C N A F C Liquid Ln xxx x F C N A F C 0005 XXX X F N A F C Dscharge xxx x F C Open F C Short F C M enu 11 Circ 3 temp s XXX X F Short F C Super xxx x F N A F Satur Cond xxx F C N A EL SE XXX X F se xF 9 Open F C Short F C M enu 12 Chiller amps 1 PrcntRLA xxx N A 3 PrcntRLA xxx N A 2 PrcntRLA xxx N A 45 M enu 13 Comp run hours Screen 4
98. p Pressure A pressure value equivalent to the leaving solution temperature minus 10 F FreezeH20 Leaving Solution A temperature value equal to the leaving solution temperature minus 4 F StpPumpDn Final Pumpdown Network R eset The reset mode can be setto network if chilled water reset via communications network is desired The chiller controller IM 549 A pressure valve equal to the FreezeStat set point minus 10 psi receives a signal from the network master panel in the range of 096 to 100 of maximum reset 23 Return Water Reset When return water is selected as the reset mode the MicroTech controller will adjust the leaving chilled water set pointto maintain a constant return watertemperature equal to the return water set point The return water temperature is sampled every 5 minutes and a proportional correction is Remote D emand Limit The controller will limit the total number of stages based on an external 4 to 20mA signal regardless of the amount of cooling actually required A 4mA orless signal will enable all Network D emand Limit Unit demand limit via network communication may be se lected if desired The chiller controller receives a demand Soft Loading The soft loading feature limits the number of cooling stages which may be energized by the controller to prevent unnec essary electrical demand and possible over shoot of the desired leaving chilled water temperature Soft loading
99. point Super heat set points are based on refrigerant circuit capacity For circuit capacity of 2596 to 5096 the superheat set point will 8 0 F Forcircuit capacity of 7596 to 10096 the superheat set point will be 10 0 F When the chiller control panel is powered up the expan sion valve will be driven closed 800 steps This ensures that the valve is fully closed prior to a call for cooling When all refrigerant circuit safeties are satisfied the controller will initiate a start sequence When the start sequence reaches open solenoid the expansion valve will be driven open to the First Open set point default 200 steps The current Forced EXV Position C hange With an increase in circuit capacity the electronic expansion valve position will be opened by a fixed percentage of its current position This change will not occur if the superheat is less than Art below the superheat set point Table 8a When Staging U p 50 75 75 100 22 TheMicroTech controller will not turn off the lag compres sor until the lead compressor is running at 50 capacity the lag compressor is running at 25 capacity and a reduction in cooling capacity is required be started first If circuits are operating and a stage down is required the circuit with the most operating hours will cycle off first circuit has the least operating hours Regardless ofthe mode selected if the lead circuit cannot operate due
100. problem Refer to Troubleshooting Power Problems below Red and green LED s off Ifthe red and green LEDs do notturn onafterpoweris applied to the controller there is likely a defective component or a problem in the controller s power distribution circuits Refer to Troubleshooting Power Problems below 4 Reconnect the Power In connector and disconnect all other connectors on the MCB Cycle power to the controller close and then open CB1 and check the power fuses If both fuses are intact go to step 5 5 Ifeitherfuse blows the MCB is defective Reconnect the keypad display ribbon cable if equipped with keypad display door Cycle powertothe controllerand checkthe power fuses If both fuses are intact go to step 6 If either fuse blows check the keypad display and the connecting ribbon cable for shorts Either one may be defective 6 Reconnectthe analog inputribbon cable Cycle powerto the controller and check the power fuses If both fuses are intact go to step 7 If either fuse blows check the ADI board the connect ing ribbon cable and the field wiring for shorts Any of these may be defective Try repeating this step after removing or swapping the ADI board 7 Reconnect digital input ribbon cable Cycle power to the controller and check the power fuses If both fuses are intact go to step 8 If either fuse blows check the ADI board the connect ing ribbon cable and the field wiring for shorts Any
101. rrent cooling stage will be displayed on the keypad display Compressor C ontrol Normal C ompressor Staging Logic The Compressor Staging Logic uses an adjustable control band and interstage timers to determine the correct number of cooling stages to activate A project ahead temperature Compressor Staging Sequence Four Compressors Available Staging U p 2 Compressor Unit Capacity Lag3 Compressor 1 Compressor CoolStaging Mode Ifthe circuitis in Cool Staging Mode and after 20 seconds the evaporator pressure remains below the freeze state set point but is greater than 2 psi the controller will transition to Low Ambient Start Mode Low Ambient Timer 360 Pressure Difference x 15 If the calculated low ambient timer value is greater than 360 the compressor will be stopped the alarm output will be activated and the display will indicate FailLowAmbStart Automatic chiller staging may be overridden by selecting Manual Cooling as the operating mode and then choosing the desired cooling stage calculation provides stable operation The total number of cooling stages for each circuit is dependent upon the num ber of cooling stages set point Staging D own Lag2 Compressor Lead Compressor 1 2 3 4 5 6 7 8 9 20 IM 549 T hree Compressors Available Staging U p Lag 3 Compressor Unit Capacity
102. rror codes network communications to the con troller was successful Ifthe Error Code reads Does not respond a communications problem has occurred For more on network diagnostics see Chapter 5 Comm Menu MonitorforWindows user s manual If a communications problem occurred check the fol lowing items Make sure hex switches on each controller are set to the correct values Make sure the controller has power supplied to it Make sure communication line is properly connected to port B Make sure the controller is level 2 by directly connecting the PC to it You must know how to change communica tions passwords to do this 7 Gotothenextcontrollerand repeatsteps 1 through 6 Do this for each controller being connected to the network Note To verify communications more quickly and eas ily use two people in the commissioning of the network Because some jobs have units located throughout a building having one person perform the commissioning procedure may be difficult When there are two people one person can stay at the PC connected to the level 1 controller and the other person can go to each individual unit controller Using a radio or other two way communi cation equipment they can indicate when a specific controller is connected and whether communications between the controllers is occurring Category group The keys in this group provide quick access to strategic me
103. rs Keypad Key Functions TheMicroTech keypad consists oftwelve pressure sensitive membrane switches Refer to Figure 11 These keys are used to step through access and manipulate the informa tion in the MicroTech controller tree structure The keypad keys are divided into four groups with two or four keys in each Keypad password When changing any menu item entry the useris prompted to enter the password The change will not be allowed until the correct password is entered The password forALS and PFS units is always the successive pressing of the following ACTION group keys ENTER ENTER ENTER ENTER Once this has been done the user can make changes to menu item entries After entering the correct password the controller will allow a 5 minute time period during which the operator may make any necessary set point adjustments Any keypad activity will reset the timer for the full 5 minutes so the password only needs to be entered once per session After 5 minutes of inactivity the password access time will expire providing protection against unauthorized users 36 Clear communications errors if found Log errors to file As the different controllers are connected to the net work their information is displayed on the Network Diag nostic Error Display screen By looking at the headings labeled Address and Error Codes network communi cations to a particular controller can be verified If there are no e
104. s required contact McQuay A voice quality direct dial telephone line is required in remote access and monitoring of the unit controller is de sired The phone line should be terminated with a standard RJ 11C modular phone plug Status menus Providechilleroperating information as and display of sensor readings The items listed under these status menus are affected by the settings underthe associated control menus and are not directly adjusted via the keypad Control menus Alladjustable control parameters and set points time sched ules control options and alarm thresholds are accessed through these menus A CAUTION Any changes to these parameters must be determined and implemented by qualified personnel with a thor ough understanding of how these parameters affectthe operation ofthe unit Negligent or improper adjustment of these controls may result in damage to the unit or personal injury Alarm menus Display any alarm conditions which may be present in the unit All alarm messages are accompanied by the date and time when the alarm occurred IM 549 Menus for Two 2 Screw Compressors U nits M enu 1 Chiller tatus OFF Manual Mode System Sw Remote Comm Remote Sw Time Clock Alarm PumpDnSw s Starting WaitForLoad CoolStageDn CoolStageUp CoolStaging Manual Cool InterStg xxx sec Hold Stage min Hi Loop M enu 2 Circ 1 satus OFF SystemSw ManualM de Alarm PumpDwnSw CycleTime xx
105. ser pressure set point de fault 380 psi the circuit will be shut down until the alarm is manually reset H igh condenser pressure stage down If the condenser pressure rises to within 20 psi of the condenser high pressure set point the controller will auto matically reduce the refrigerant circuit s capacity by one cooling stage every 10 seconds until the condenser pressure falls below the 20 psi threshold HiCondPre 20 Iftwo high pressure stage downs occur within a 60 minute period the normal interstage timer will be extended to 15 minutes to inhibit any stage up requests Normal chiller staging will resume once this 15 minute timer expires 27 H igh condenser pressure stage hold If the condenser pressure rises to within 30 psi of the condenserhigh pressure set point the controller will hold the circuit at its current capacity Normal chiller operation will resume once the condenser pressure drops below the high pressure stage hold threshold No liquid start If liquid refrigerant is not present at the compressor s injec tion port within 20 seconds of a start request the circuit will be shut down and the fault will be recorded The circuit will automatically attempt to re start after the cycle timer ex pires If a no liquid start is recorded during the second start attempt the circuit is shut down and the alarm output is energized No additional starts will be attempted until the alarm is manually cleared No liquid run
106. signals from sensors transducers and switches are received by the ADI Board and then sentto the Micropro cessor Control Board for interpretation It receives control signals from the Microprocessor Con trol Board through a 50 conductor ribbon cable THER C units with more than two EXV s Control instructions for the board are generated by the M250 controller CRN RED YEL TOR IM 549 cu os oraz 03 PU tse 408257 9 PART NUMBER mio 510 Ee Analog O utput Board AOX Board With ptional SpeedTrol The AOX Board converts control instructions from the M 250 s driving a variable speed condenser fan Each AOX Board is expansion bus into an analog control signal suitable for factory set via jumperto provide output signal of 0 10 VDC Figure6 AOX board d n CAD ex ex Keypad D isplay The Keypad Display is the primary operator interface to the points can be modified from this keyboard if the operator has unit All operating conditions system alarms and set points entered a valid operator password can be monitored from this display and all adjustable set Figure 7 Keypad display CATEGORY STATUS CONTROL SWITCH 8 IM 549 Sensors and Transducers Standard Sensors Evaporator Leaving Water Temperature Evaporator Refrigerant Pressure Circuit 1 2 3 amp 4 Cond
107. ssure The typical range for evaporator sen sors is 0 to 150 psig with a resolution of 0 1 psig Condenser pressure sensors have a range 01010 450 psiand a resolution Figure9 of 0 5 psig The pressure transducers require an external 5 VDC power supply to operate which is provided by the MicroTech controller This connection should not be used to power any additional devices Red dot condenser Blue dot evaporator Liquid Presence Sensor The presence of liquid refrigerant is determined by a liquid level sensor mounted at the liquid injection port in the compressor casting Wheneverthe glass prism sensor tip is Figure 10 IM 549 H JHI in contact with liquid the sensor output signal will be high gt 7VAC If no liquid is detected the output will be low OVAC 5 bi GLL100501 MA me 11 Sensor Locations 2 Compressor Unit Figure 11 12 Table s Evaporator Leaving Water Temperature 605830 03 Evaporator Pressure Transducer Circuit 1 658168B 011 Evaporator Pressure Transducer Circuit 2 658168B 011 Condenser Pressure Transducer Circuit 1 658168B 021 Condenser Pressure Transducer Circuit 2 658168B 021 Evaporator Water Temperature Reset Outdoor Air or Zone N A Demand Limit N A Evaporator Entering Water Temperat
108. st menu in the tree structure B NEXT Pressing NEXT shifts the display to the next menu Note When menu 27 is currently in the display the last menu in the menu tree structure pressing NEXT causes an end of menus message to appear in the display Pressing NEXT again causes the display to wrap around to Menu 1 the first menu in the menu tree structure Item group The keys in this group are for stepping from item to item within a menu A PREV Pressing PREV shifts the display to the previous item in a menu Note When the first item in a menu is currently in the display pressing PREV causes an end of items message to appear in the display Pressing PREV again causes the display to wrap around to the last item in the menu B NEXT Pressing NEXT shifts the display to the next item in a menu Note When the last item in a menu is currently in the display pressing NEXT causes an end of items message to appear in the display Pressing NEXT again causes the display to wrap around to the first item in the menu Action group The keys in this group are for making changes to unit control parameters for clearing alarm conditions Note Before change to a parameter can be made or before an alarm can be cleared the display prompts the user with an Enter Password message At this point the password must be entered before the user can continue with the action Enter
109. t the trunk Ifthereis no continuity forone ormore conductor pairs there may bea break in thetrunk ortheterminations atone or more controllers may have been mixed up Table 13 Port B voltages AM P type connector Port B RS 485 Acceptable Voltage Reading Signal T erminal 3 0 0 3 Vdc 2 0 0 3 Vdc 0 0 0 2 Vdc t 4 3 Ground 5 IM 549 Table14 e amp work communicationsfield wiring terminals Network C omm Field T erminal t Ground Controller CSC 11 11 T11 GND Reciprocating Chiller TB 7 138 TB7 137 TB7 139 Screw Chiller TB4 54 TB4 53 TB4 55 Figure 18 AM P connector terminal configuration Fuse 1 Port A Port B Communications Fuse Bussman MCR 1 4 Level 1 controller connection In order for the chillers and other level 2 controllers in a network to connect and communicate with the level 1 con troller the level 1 controller is connected first 1 Set the network address to 00 level 1 See Addressing the Controllers above for more information 2 Pushthecircuitbreaker CB 1 buttonto powerup the CSC and verify thatthere is powerto the MCB byobserving the LEDs 3 Check the voltages of port B on field wiring terminals TB2 UseaDC voltmeter to test for proper voltages With the ground lead on the control panel chassis ground check the voltage at the and ground terminals Refer to Table 13 for the correct voltage levels
110. t to flow through its con tacts When the controller removes the trigger signal the relay s resistance becomes very high causing the current flow to stop The status of all outputs are shown by individual red LEDs for ease of determining output status Interlock wiring Allinterlock wiring to field devices suchas flow switches and pump starters is provided by the installing contractor Refer to the Field Wiring Drawing as well as the unit wiring sche matics and typical application drawings at the end of this manual for details External alarm circuit The MicroTech panel can activate an external alarm circuit when an alarm or pre alarm condition is detected A 24VAC voltage source is available at field wiring terminal 107 to power an external alarm device such as a bell light or relay An alarm annunciator rated for a maximum load of 1 8 Amps at 24VAC is to be provided and wired by the installing contractor The normal and alarm states forthe 24VAC alarm signalare programmable by the operator Available settings are Pre alarm annunciation Close or Open or Blink Alarm annunciation Close or Open 18 start up technician priorto starting the unit The MicroTech controller contains default set points which will be appropri ate for most common installations Power wiring 115VAC powerforthe controltransformeris derived fromthe 3 phase power connection provided by the electrical con tractor A separate disconnect for the c
111. three digit numbers indicates Centigrade values 46 IM 549 M enu 17b Lvg evap spts valuesfor 134a refrigerant E MISI 07 5 2 3 L3 erret EE 0110 0005 ResetO pt None Return 4 40 Ma Network Ice Outdoor 399 831 99 459 00950 MaxOaTRst 300 C11 Note the minus sign is not displayed with three digit numbers indicates Centigrade values M enu 18 Soft load spts EE iesdbelaye ssec M enu 19 Compressor spt D isplay Factory Set Point Lead Lag Auto 1 gt 2 gt 3 1 gt 3 gt 2 2 gt 1 gt 3 Auto 2 gt 3 gt 1 3 gt 1 gt 2 3 gt 2 gt 1 CLEES 3 MinsrSToocmin MinSP ST xx min M enu 20a H ead presspt valuesfor R 22 refrigerant ___ 70888 60100 4600 2 55 70100 483 6890 140 156 10040 690 966 4 beadBandMut xx s 400 2760 1 300990 20706830 6 Suserzwx 50400 40216 Note indicates Centigrade values M enu 20b H ead presspt valuesfor 134a refrigerant D isplay Factory Set Point
112. to an alarm condition or if off on cycle timers the controller will switch to the lag circuit step pulses by the EXV board which in turn drive the valve s 3 phase DC stepper motor open or closed as required A control range of 0 steps full closed to 760 steps full open is available to provide precise control of the valve position suction line temperature is compared against the Suction Line Temperature set point evaporator temp plus superheat spt to calculate superheat error Err The current suction line temperature is also compared with the previous reading to calculate delta superheat error DErr These two error values are used to determine the magnitude and direction of the expansion valve positioning signal A new valve positioning signal is calculated every 10 seconds however the interval at which these signals are issued to the EXV board is dependent on the magnitude of the required positional change If no change is required the interval will be 60 seconds With a decrease in circuit capacity the electronic expansion valve position will be closed by a fixed percentage of its current position Table 8b When Staging D own 7 596 1896 5096 4096 IM 549 EXV Evaporator Pressure C ontrol The electronic expansion valve control will maintain a con stant superheat for suction line temperature up to 60 F For suction line temperatures greater than 61 F the expansion valve control logic
113. tput 15 0 18 Output 16 0 19 Output 17 0 20 Output 18 0 21 Output 19 0 22 Output 20 0 23 Output 21 0 24 Output 22 0 25 Output 23 0 26 Output 24 0 27 Output 25 0 28 Output 26 0 29 Output 27 0 30 Output 28 0 31 Output 29 0 32 Output 31 0 33 Output 3220 34 Output 33 0 35 Output 34 0 36 Output 35 0 37 Output 36 0 38 Output 37 0 39 Output 38 0 Puta input 0 Close 42 152 00000000 i 0 Open 1 5 o e e 2 e 2 2 N 0 0 3 00000000 0 Open 1 Closed 00000000 9 Open 1 Closed 48 592 Aie xo Actual Vc Value M enu 29a Alarm spts valuesfor R 22 refrigerant 1 SisPumpDn kPa 2 FwPumpbown No Pa 00400 7548 380062 28042 09322839 Note indicates Centrigrade values M enu 29b Alarm spts values for 134a refrigerant D isplay Factory Set Point 1 smPumppnzepsi s 1488 FullPumpbown No OSS 3 Freezstat xxpsi kPa 26 179 4 26 27 179 4 FreezH20 xx x F C 36 0 2 3 0 0 40 0 17 5 4 5 5 HiPress xxxpsi kPa
114. ts in any of these components can affect the MCB and thus the entire control system Power problems can be caused by an external short which can blow a fuse or a defective component which can either blow a fuse or create an excessive load on the power supply An excessive load can lowerthe power supply voltages to unacceptable levels Use the following procedure to isolate the problem Note This procedure may require two or three spare MCB fuses 1 Verify that circuit breaker CB1 is closed 2 Remove the MCB Power In connector and check for 9 Vac between the terminals on the plug corresponding to terminals 2 and 3 on the board Figure 2 Then check for 9 Vac between the terminals on the plug corresponding to terminals 1 and 3 on the board Readings of 9 12 Vac are acceptable If 9 Vac is present between both sets of terminals go to step 3 If 9 Vac is not present between both sets of terminals check both transformers and all wiring between the 115 Vac source and the Power In plug 3 Remove power from the controller by opening circuit breaker CB1 Check the MCB power supply input fuses Fl and F2 with an ohmmeter See Figure 3 A good fuse will have negligible resistance through it less than 2 ohms If either or both fuses are blown replace them Go to step 4 If the fuses are intact the MCB is defective 30 itis likely that the MCB is defective However this can also occur in some instances if there is a power supply
115. uisLn xxx x Lvg xxx x F OA LCnWT xx xx F C Capacity ot IM 549 M enu 26 42 curr alarm 00 gt __3 Evap xxpsi kPa 4 Cond x x psi kPa SuctLine xxx x F C LiquisLn xxx x F C Evap Lvg xxx x F C OA LCnWT 2xx xx F C Capacity 000002 43 M enu 27 1 Prev alarm Screen D isplay 6 7 8 1 Current Alarm lxxx 2 Current Alarm 2 3 Current Alarm 3 4 Current Alarm 4 5 Current Alarm 5 Menus for T hree 3 Screw Compressors U nits M enu 1 Chiller tatus reen Screen OFF Manual Mode System Sw Remote Comm Remote Sw Time Clock Alarm PumpDnSw s Starting WaitForLoad CoolStageDn CoolStageUp CoolStaging Manual Cool ___2 ___ 3 SE 4 InterStg xxx sec Hold Stage min Hi Loop M enu 2 Circ 1 satus Screen Screen OFF SystemSw Alarm PumpDwnSw CycleTime xx WaitFlooded waitF lodded xxx Ready PumpingDown Starting Pre Purge Opened EXV LowAmbStart Cooling Cap xxx 44 M enu 28 2 Prev alarm Screen 1 5 Curent alarm
116. until either the evaporator refrigerant pressure drops IM 549 T elephone line for remote modem access A voice quality direct dial telephone line is required if remote access and monitoring of the unit controller is desired The phone line should be terminated with a standard RJ 11 modular phone plug may vary depending on various options which may be installed on the chiller mode is in effect If an alarm condition exists which prevents normal operation of both refrigerant circuits the chiller will be disabled and the display will indicate OFF AllCompAlarm MicroTech controller allows the operator to manually set the chiller to an off mode via the keypad The display indicates this operating mode with the message OFF ManualM ode Assuming none of the above Off conditions are true the controller will examine the internal time schedule to deter mine if the chiller should start The operating mode will be OFF TimeClock if the time schedule indicates an off time period indicates the presence of chilled water flow If flow is not proven within 30 seconds the alarm output will be activated and the chiller will continue to wait for proof of chilled water flow When chilled water flow is re established the alarm will be automatically cleared Chilled Water Set point plus the adjustable Control Band plus the Start up Delta Temperature Set point the controller will select the refrigerant circuit with the lowest nu
117. ure 705830B 02 Condenser Entering Water Temperature or Outside Air 705830B 01 Total Unit Amps Suction Temperature Circuit 1 705830B 02 Suction Temperature Circuit 2 705830B 01 Liquid Line Temperature Circuit 1 705830B 01 Liquid Line Temperature Circuit 2 705830B 02 Inside of control box on power amp control panels Back of control box IM 549 Analog Inputs Analog inputs are used to read the various temperature and internal regulated 5 VDC and 12 VDC supplies provide the pressure sensors installed on the chiller as well as any correct operating voltage for the sensors customer supplied 4 20mA reset signals The controller s Table4a Analog inputs 2 compresor units Sewwrlocton Evaporator Leaving Water Temp Leaving chilled water nozzle Evap Pressure Transducer Cir 1 Common cir 1 suction line Evap Pressure Transducer Cir 2 Common cir 2 suction line Cond Pressure Transducer Cir 1 Compressor 1 discharge cover Cond Pressure Transducer Cir 2 Compressor 2 discharge cover Transducer Power Voltage Ratio Internal Reset Evap Water Temperature External 4 20 mA signal Demand Limit External 4 20 mA signal Entering Evaporator Water Temp Entering chilled water nozzle O A T Ent Cond Water Temp Back of the control box Condenser Leaving Water Temp Leaving con
118. ure dead band Minimum and maximum fan speed is defined by the Figure 14 is equal to or greater than the stage up set point the controller starts an additional fan stage The accumulated totalis zero whenevera fan stage change occurs orthe condenser pressure falls inside the dead band Fan stages 5 or 6 will not be enabled unless the circuit capacity is greater than 50 stages if a rapid rise in pressure is detected controller decrements a fan stage The accumulated total is set to zero whenever a fan stage change occurs or the condenser pressure rises inside the dead band Fan stages 5 or 6 will automatically be disabled whenever the circuit capacity falls to 5096 or less minimum and maximum lift pressure set points so that when the condenser pressure is below the dead band the fan speed will be setto 096 and when the condenser pressure is above the dead band the fan motor speed will be set to 10096 10096 9096 8096 7096 6096 5096 4096 SpeedTrol motor voltage 3096 20 10 0 10 9 8 7 6 5 4 3 2 1 0 Input voltage from AOX board Pumpdown Automatic Pumpdown As the system chilled water requirements diminish the compressors willbe unloaded As the system load continues to drop the electronic expansion valve will be driven to 0 steps closed and the refrigerant circuit will go through a
119. ust the contrasttrim pot which is located on the back ofthe keypad display assembly Back light not lit The Keypad Display Interfaces supplied with the MicroTech control panel is equipped with a back light If the light does not come on check for 5 Vdc at terminal 9 on the IDC connector on the KDI and for 5 Vdc on the field wiring terminal strip Check for 5 Vdc on the IDC connector on the MCB aux IM 549 circuit breaker CB1 open measure the resistance be tween field terminals DC GRD and 13 Vdc It should steadily rise to a value greater than 5000 ohms within approximately 30 seconds Ifthe resistance rises above 5000 ohms go to step 13 If the resistance does not rise above 5000 ohms the MCB is defective 13 at a time reconnect the modem and each AOX 4 board as applicable Each time a component is recon nected measure the resistance between field terminals DC GRD and 13 Vdc It should steadily rise to a value greater than 5000 ohms If the resistance rises above 5000 ohms repeat this step until the modem and all AOX 4 boards as appli cable have been checked out If the problem persists it is indeterminate Obtain factory service If the resistance does not rise above 5000 ohms the modem or the AOX 4 board just connected is defective With the power plug disconnected the resistance across AOX 4 board s DC and terminals should not be less than 3 million ohms Figure15 M CB pow
120. valuesfor 134a refrigerant D isplay Factory Set Point 1 _StpPumpbn xxpsi kPa 2 110000 3 FrreezStat xxpsi kPa 26 179 4 26 27 179 __4 FreezH20 xx x F C 36 0 Q 3 0 0 40 0 17 5 4 5 __5 HiPress kPa 276 1904 180 326 1242 2249 Note indicates Centigrade values IM 549 49 Menu 27 Misc setup Display Factory Set Point Unit Type ALS 205 ALS 220 ALS 235 ALS 250 ALS 265 ALS 280 __ 9600 Pre Alarm Blink Open Blink Open Closed Alarm Closed Blink N O Closed Blink N O Blink N C Blink N C OAT Select None None Lcl Rmt Rmt Amb Lockout No No Yes Yes EntEwpAdj 0 0 FCC 20 20 138138 1 0 0psi kPa 2 0 2 0 13 8 13 8 IDENT 5 320193 Current Alarm Current Alarm Evap x x psi kPa Evap x x psi kPa Cond x x psi kPa Cond x x psi kPa SuctLine xxx x F eC SuctLine xxx x F C LiquisLn xxx x F C LiquisLn xxx x F C Evap Lvg xxx x F C Evap Lvg xxx x F M enu 29 2 curr alarm Display Display Current Alarm lCumentAlarm D isplay D isplay CumentAlarm CumentAlarm Current Alarm 1 Current Alarm Cond xx psi Pa FECI CERS BCEE 9 39 Fan Stage x 5
121. vel is low Table5a Digital inputs 2 compresor unit mme Mechanical High Pressure S witch Circuit 1 Normal Liquid Presence Switch Compressor 1 Normal Motor Protect Compressor 1 Normal Oil Level Sensor Compressor 1 Normal Reserved System Switch S1 Run Phase Voltage Monitor Normal Pump Down Switch Circuit 1 Pumpdown Mechanical High Pressure Switch Circuit 2 Normal Liquid Presence Switch Compressor 2 Normal Motor Protect Compressor 2 Normal Oil Level Sensor Compressor 2 Normal Reserved Unit Remote Stop Switch Run Evap Water Flow Switch Normal Pump Down Switch Circuit 2 Pumpdown SI U1 BY N tal m e m m m m m Table5b Digital inputs 3 compresor unit Mechanical High Pressure S witch Cir 1 Alarm Normal Liquid Presence Sensor Compr 1 No Liquid Liquid Motor Prot Compr 1 Alarm Normal Not Used Not Used System On Off S witch On Phase Volt Monitor Compr 1 Alarm Normal PumpDown Switch Compr 1 Normal Pump DN Mechanical High Pressure Switch Cir 2 Alarm Normal Liquid Presence Sensor Compr 2 No Liquid Liquid Motor Prot Compr 2 Alarm Normal Not Used Not Used Remote Start Stop Switch Stop Start Evap Water Flow Switch No Flow Flow PumpDown Switch Compr 2 Normal PumpDn Mechanical High Pressure Switch Cir 43 Alarm Normal Liquid Presence
122. will maintain a constant evaporator tem perature to avoid overloading the compressor motor The Chilled Water Reset ptions Chilled Water Reset Remote 4 20mA The controller resets the chilled water set point based on an external 410 20mA signal At4 mA orless no reset will occur At 20mA the chilled water set point will be reset by an Figure 12 100 control point will be the Evap Temp set point default 50 F and the control method will be the standard MicroTech Step and Waitalgorithm Whenthe suction line temperature drops below 57 F the MicroTech logic will resume normal super heat control amount equal to the value stored in the Maximum Reset set point The reset schedule is linear and may be calculated using Figure 12 80 60 40 20 Percent of maximum reset 0 1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 External 0 10mA signal Ice M ode The MicroTech controller has dual chilled water set points when ice mode is selected With an external reset signal of 4 orless the chilled water reset will be zero If the external reset signal is greater than 4mA maximum reset will be in Table9 effect For installations requiring operation in ice mode the following set points should be adjusted to accommodate the reduced system temperature and pressures SetPoint Monitos FreezeStat Low Eva
123. xpsi kPa 380 2622 20 60 138 414 0 0 40 0 17 5 4 5 280 426 1932 2939 Note indicates Centigrade value M enu 23b Alarm spts values for 134a refrigerant D isplay Factory Set Point StpPumpDn xxpsi kPa 4 96 2 22 13 151 FullPumpDownz NS No yes FreezStat xxpsi kP a 26 179 4 26 27 179 FreezH20 xx x F C 36 0 2 3 0 0 40 0 17 5 4 5 Hi Press xxxpsi kPa 276 1904 180 326 1242 2249 Note indicates Centigrade value 24 M isc stup Display Factory Set Point Unit 15125 ALS140 ALS 155 ALS170 ALS 175 ALS 185 ALS 195 PFS150 PFS165 PFS180 PFS190 PFS200 2 Units Engis English Pre Alarm Blink Open i Blink Open Closed Closed Alarm Closed Blink N O Blink N C OAT Select None None Lcl Rmt Rmt SES 1 105555 13 EvpAdj 0 0psi REEL 32 ER A S EE S 5 loNetthamesble Closed Blink N O Blink N C Menu 25 1 curr alarm P Current Alarm 2011 1101 gt 3 Evap xxpsi kPa 4 Cond xxpsi kPa SuctLine xxx x F C Liq

Download Pdf Manuals

Related Search

Related Contents

22 Mbps Wireless Access Point    TDSHーBA 東芝誘導灯用リニューアルプレート取扱説明書  November 30, 2012 Specification AFFV Aircraft  Colocacion y limpieza gres porcelanico    Manual de usuario - ORFEO, Módulo de validación  Whirlpool LE6090XS User's Manual    Wile 55 Descargar  

Copyright © All rights reserved. Failed to retrieve file