Guide to the EEV system User manual - Gafco
Contents
1. C LOWER LIMIT THRESHOLD UPPER LIMIT 0 C Superheat set point LP pressure switch calibration C design evaporation temperature design evaporation temperature compressor limit 10 15 C design condensing temperature HP pressure switch calibration C Tab 9 a The pressure switch calibration value normally expressed as pressure must be converted to C saturated Code 030220215 rel 1 4 25 04 2007 23 control control 10 Troubleshooting The following table lists a series of situations of malfunctions that may occur when starting and operating the driver and the electronic valve These cover the more common problems and provide an initial response to help resolve the fault PROBLEM CAUSE SOLUTION Check that the pressure and the temperature measured are correct and that the probe position is correct Check that the minimum and maximum pressure parameters for the pressure transducer set on the driver correspond to the range of the pressure probe installed Check the correct probe electrical connections The type of refrigerant set is incorrect Check and correct the type of refrigerant parameter The type of valve set is incorrect Check and correct the type of valve parameter Check the movement of the valve by placing it in manual control The valve is connected incorrectly and closing or opening it completely One complete opening must rotates in reverse and Is open bring a decrease in the sup2. LOP protection disabled In the start up phase LOP protection ineffective the low pressure protection is activated only for units with compressor on Solenoid blocked board Insufficient refrigerant The valve is connected incorrectly rotates in reverse and Is open Stator broken or connected incorrectly Valve stuck closed Code 030220215 rel 1 4 25 04 2007 SOLUTION Check the controller condenser settings giving the parameters blander values e g increase the proportional band or increase the integration time Note the required stability involves a variation within 0 5 bar If this is not effective or the settings cannot be changed adopt electronic valve control parameters for perturbed systems see paragraph 8 3 Check for the causes of the swings e g low refrigerant charge and resolve where possible If not possible adopt electronic valve control parameters for perturbed systems see paragraph 8 3 As a first approach decrease by 30 to 50 the proportional factor Subsequently try increasing the integration time by the same percentage In any case adopt parameter settings recommended for stable systems Increase the superheat set point and check that the swings are reduced or disappear Initially set 13 C then gradually reduce the set point making sure the system does not start swinging again and that the unit temperature reaches the control set point Activate the
3. HiTcond prot integration time Tab 8 c Recommended parameters for AIR CONDITIONERS CHILLERS Variable cooling capacity steps Perturbed AIR CONDITIONERS CHILLERS inverter system SHset Superheat set point K pro PID proportional gain i PID integration time d PID derivative time LowSH LowSH prot threshold LowSH Ti LowSH prot Integration time 15 20 150 100 I I PROTECTOR MOPTI S S Ln je sec sec C sec ze sec ge ec Ln N N MOP prot maximum MOP HiTsurr superheated gas temperature limit MOP Delay hd a activation delay HiTcond HiTcond prot threshold UN oO 30 ec 6 60 N o Mm UN N UN UN oO oO HiTcond prot integration 30 WN D O N oO HiTcond Ti time Tab 8 d Recommended parameters for AIR CONDITIONERS CHILLERS continued 3 The LOP threshold is set between the limit of the low pressure switch and the design evaporation temperature If using a water glycol mix the threshold must be adapted to values that are ate least 5 C lower than the evaporation temperature The HiTcond protection can only be enabled if the condenser probe is connected to the driver and its value is sent via LAN Otherwise the Integration time must be set to 0 Code 030220215 rel 1 4 25 04 2007 N control 9 Start up When starting control for the first time make sure that 1 the electronic valve opens and starts controll
4. KKK AR ae ro 139 9 86 7 67 7 61 4 ID 9 84 thread ID 9 84 thread 3 8 1 2 SAE 5 51 341 2 42 2 42 in 0 35 3 4 thread in 0 35 3 4 thread Tab 2 a 2 1 Diagram of the refrigerant circuit Below is a typical diagram of the refrigerant circuit with the components that are always featured and the optional components indicating the typical position of the EV valve and the sensors required for the calculation of the superheat The sight glass is not strictly necessary however is useful when seeking the cause of malfunctions The solenoid valve is generally used in refrigeration systems showcases cold rooms to stop the flow of refrigerant when the utility is not cooling Condensatore Condenser Misura del surriscaldamento Superheat detection fi Compressore Compressor Evaporatore Evaporator 82 IM E 3 Valvola di espansione E V E 4 expansion valve Fig 2 b installation 2 2 In line filter Always install a mechanical filter before the refrigerant inlet with both welded valves E2V S and valves with threaded fittings E2V RB For the latter a filter is supplied inside the packaging that can be placed directly in the valve inlet pipe If the installation is bi directional flow of refrigerant in both directions reverse cycle heat pumps a bi directional liquid gas filter should be fitted on both expansion valve connections or o
5. LowSH thresholds by at least 2 C on the showcases involved The valve is significantly oversized Replace the valve with a smaller equivalent Check the calculation in reference to the ratio between the rated cooling capacity of the evaporator and the capacity of the valve if necessary lower the value Liquid returns to the compressor only when starting the controller after being OFF The valve opening at start up parameter Is set too high Code 030220811 rel 1 0 26 04 2007 24 PROBLEM CAUSE The condensing pressure swings The superheat swings even with the valve set in manual control in the position corresponding to the The superheat value swings around the set point with an amplitude greater average of the working values than 4 C The superheat does NOT swings with the valve set in manual control in the position corresponding to the average of the working values The superheat set point is too low MOP protection disabled or In the start up phase nefecive with high evaporator temperatures the evaporation pressure is high Refrigerant charge excessive for the system or extreme trans tory conditions at start up for showcases only The Valve opening at start up parameter is set too low The driver in pLAN or tLAN configuration does not start control and the valve remains closed The driver in stand alone configuration does not start control and the valve remains closed
6. both software that hardware is part of the controller user interface Finally it should be noted that for applications with lower cooling capacities the use of an on off solenoid valve is recommended rather than the battery module considering the lower cost of the valves compared to the batteries 7 Control devices basic parameter settings To be able to start control some fundamental parameters need to be set e Refrigerant Model of valve e Minimum value pressure of the pressure transducer installed barg e Maximum pressure value of the pressure transducer installed barg Battery module fitted where available All the other parameters can be left at the default values and configured at a later stage Nonetheless it Is suggested to read the following paragraphs and set the recommended parameters for the different applications paragraph 8 3 Code 030220215 rel 1 4 25 04 2007 control control 8 Control devices advanced parameter settings The control of the electronic valve can be divided into two categories superheat control with reference to the corresponding set point and control of unit safety with protectors that are activated only if the pressure or temperature reach dangerous values that can be set by the user 8 1 Superheat control parameters The superheat control function involves calculating the position of the valve based on the reading of the superheat and the correspondin
7. low check the electrical connections and or replace the valve The valve opening at start up parameter is too high on many Decrease the value of the Valve opening at start up parameter showcases in which the control set on all the utilities making sure that there are no repercussions on point is often reached for the control temperature multiplexed showcases only Ihe PB ee ae au Increase the value of the valve control delay after defrosting is too short for MasterCase MasterCase 2 and mpxPRO only alannah The superheat measured by the Check that the LowSH threshold is greater than the superheat driver after defrosting and before value measured and that the corresponding protection Is activated reaching operating conditions Is very integration time gt Osec If necessary decrease the value of the Liquid returns to the low for a few minutes integration time ler yaer The superheat measured by the Set more reactive parameters to bring forward the closing of the multiplexed driver does not reach low values but valve increase the proportional factor to 30 increase the there is still return of liquid to the integration time to 250 sec and increase the derivative time to 10 showcases only compressor rack Sec Stagger the start defrost times If this is not possible if the Many showcases defrosting at the conditions in the previous two points are not present increase the same time superheat set point and the
8. valve body in a wet rag before starting welding never point the flame directly at the valve body never exert twisting or deforming forces on the valve body or on the pipes connected to it do not exert excessive pressure on the stator when fitting it to the valve so as to avoid deforming the plastic cap at the bottom of the stator do not hit the valve with hammers or other tools nor drop the valve e never place the valve near magnets and or magnetic fields e take extreme care to ensure no impurities enter the refrigerant circuit e do not install or use the valve if there is deformation or damage to the visible parts outer cap and connection pipes e do not install following strong impact for example after dropping the valve e do not install or use if the stator winding contact carrier or connector are damaged Fig 2 8 3 Positioning the probes The purpose of the control action of the electronic valve is to maintain the refrigerant superheat at the evaporator outlet around the desired value superheat set point In general if the superheat is greater than the set point the controller will open the valve and vice versa To measure the superheat the driver uses 2 probes that measure the suction temperature and the evaporation pressure of the refrigerant at the evaporator outlet The pressure Is used to calculate the saturated evaporation temperature and the difference between the suction temperature and the saturated evaporati
9. 21C0 from 0 5 to 7 barg In this case however broken disconnected alarms may be signalled during the periods in which control is not active When the unit is off in fact the pressure at the evaporator outlet may exceed the maximum measurement of the transducer due to the balancing of the pressure in the refrigerant circuit in this case the driver will signal a probe fault alarm 5 Electrical connections 5 1 Connecting the valve to the driver The following operations are required for the connection of the valve to the driver A Completely insert the stator into the valve body and tighten the locking nut Never leave the stator in place without the locking nut or with the nut partially unscrewed as water may infiltrate inside B Fit the cable with the co moulded IP67 connector code E2VCAB connecting the connector to the stator and fastening it carefully with the screw provided IP67 protection Is not guaranteed if the screw Is not properly secured A shielded cable code E2VCABS is also available where necessary Pay special attention to the polarity of the connectors contact no 4 which on the stator Is facing the valve body is wider than the other three Do not forcefully insert the connector unless you are sure the orientation Is correct If the orientation is incorrect the valve will not be able to move correctly Bbis Alternatively a standard DIN 43650 B connector code E2VCON can be used wiring the 4 poles to a 4 wi
10. 8 8 Vista di lato EVBATBOX00 Vista di lato EVBATBOX10 Vista da dietro entrambi i modelli Side view EVBATBOX00 Side view EVBATBOX10 Rear view both models Fig 5 Code 0302202 15 rel 1 4 25 04 2007 15 control 6 Electronic valve control devices There are different types of driver and different controllers with built in drivers 6 1 Drivers The drivers EVD family mainly differ as regards e type of pressure transducer ratiometric or 4 20 mA e user interface for programming the parameters e local network connection tLAN pLAN RS485 supervisor A pLAN or tLAN connection is fundamental if the driver needs to be used together with a programmable pCO controller that manages the refrigerating showcase air conditioner This gives optimum results both as concerns the programming interface this can be customised the operation of the driver based on the needs of the unit and the sharing and management of probes alarms and signals If not compatible with the pLAN or tLAN the driver must operate in stand alone mode activating and deactivating control of the valve based on the status of the digital input e digital input open the driver closes the valve and deactivates control e digital input closed the driver opens the valve and starts control In some models positioner operating mode can be activated in which the driver moves the valve exclusively based on an analogue input signal 4 20 mA or 0 10 V corresponding
11. Agency Cod 030220811 Rel 1 0 26 04 07
12. Guide to the EEV system CAREL ac TOA BTT User manual LEGGI E CONSERVA gt QUESTE ISTRUZIONI READ AND SAVE THESE INSTRUCTIONS Technology amp Evolution User manual IMPORTANT WARNINGS CAREL bases the development of its products on decades of experience in HVAC on the continuous investments in technological innovations to products procedures and strict quality processes with in circuit and functional testing on 100 of its products and on the most innovative production technology available on the market CAREL and its subsidiaries nonetheless cannot guarantee that all the aspects of the product and the software included with the product respond to the requirements of the final application despite the product being developed according to start of the art techniques The customer manufacturer developer or installer of the final equipment accepts all liability and risk relating to the configuration of the product in order to reach the expected results in relation to the specific final installation and or equipment CAREL may based on specific agreements acts as a consultant for the positive commissioning of the final unit application however in no case does it accept liability for the correct operation of the final equipment system The CAREL product is a state of the art product whose operation is specified in the technical documentation supplied with the product or can be downloaded even prior
13. MOP protection by setting the threshold to the required saturated evaporation temperature high evaporation temperature limit for the compressors and setting the MOP integration time to a value above 0 recommended 4 seconds To make the protection more reactive decrease the MOP integration time Apply a soft start technique activating the utilities one at a time or in small groups If this is not possible decrease the values of the MOP thresholds on all the utilities Check the calculation in reference to the ratio between the rated cooling capacity of the evaporator and the capacity of the valve if necessary lower the value see paragraph 8 1 Check the pLAN tLAN connections Check that the pCO application connected to the driver where featured correctly manages the driver start signal Check that the driver is NOT in stand alone mode Check the connection of the digital input Check that when the control signal is sent that the input is closed correctly Check that the driver is in stand alone mode Set a LOP integration time greater than 0 sec Make sure that the LOP protection threshold Is at the required saturated evaporation temperature between the rated evaporation temperature of the unit and the corresponding temperature at the calibration of the low pressure switch and decrease the value of the LOP integration time Check that the solenoid opens correctly check the electrical connections and the operation o
14. RPS 3 2 IGOR T ie 3 3 Positioning for reverse cycle heat pumps EV in bi directional operation Eo _ulmstallne 125 1 vs tia 4 1 A RARA AR 4 2 OLII GRECI O A I 5 Electrical connedionSir ecc j 5 1 Connedine Ie VIVE TONE ANVET oien a O E T T T NTA 52 Probe LA er aan 55 Battery module connection for dosing A e iiaia lat KE aE AE AE AE AKANA sna A 6 Electronic valve control devices num aan BEN DENE EP rn es assessment Coeli o 1 Controldevices Dasic parameter settings meri 8 Control devices advanced parameter SettingS sssssssssssssssssssessesssesssessssssesssssssesscsssessscssesssessueesssssesssesssecsscsnessueesuessessaesssesascssessuceasessessuessseesessaessueessesnessneesseesseess 8 1 SUENO OS road g 8 2 Proteccion FUNCTION Control paame SUS AAA A AEA a dt 8 3 A O E OTE TEE N ONE Don RN 9 1 A ee hc 9 2 AAA PP A II Tee ET 22 10 OUDISSNOO MM aan 24 Code 030220811 rel 1 0 26 04 2007 installation 1 Selecting the valve The electronic expansion valve must be sized based on the cooling capacity of the evaporator it serves For the correct selection of the valve see the EV E V valve selection manual 030220815 downloadable from www carel com Alternatively guided selection software Is available on ksa carel com Incorrect sizing may cause various problems If the valve is undersized the performance of the system will be affected as it will not be possible to reach the a desired temperatur
15. aries are warned of the possibility of such damage Disposal the products are made from metal parts and plastic parts In reference to European Union directive 2002 96 EC issued on 27 January 2003 and the related national legislation please note that 1 WEEE cannot be disposed of as municipal waste and such waste must be collected and disposed of separately 2 the public or private waste collection systems defined by local legislation must be used In addition the equipment can be returned to the distributor at the end of its working life when buying new equipment 3 the equipment may contain hazardous substances the improper use or incorrect disposal of such may have negative effects on human health and on the environment 4 the symbol crossed out wheeled bin shown on the product or on the packaging and on the instruction sheet indicates that the equipment has been introduced onto the market after 13 August 2005 and that it must be disposed of separately 5 In the event of illegal disposal of electrical and electronic waste the penalties are specified by local waste disposal legislation Code 030220811 rel 1 0 26 04 2007 4 Contents le Selecting a 15 AAA II OI O aaa 25 Inst lne MEA ia bad 2 1 RIRI OU IVE TIS ING CUR e 1 tsa tc de ence tee tubes IAA 2 2 bici 2 3 FOW of femiecrantand spahakonentation OEL ANN en O EA eae ote Maes 2 4 coi 5 PRositionme ME DIODOS ns van anne ans 3 deal POSIION ON
16. aste inside the socket The inside diameter of the socket must a little larger no more than 0 5 mm than the diameter of the probe The probe socket assembly should then be covered with heat insulation Omax 4 5mm pasta conduttiva conductive cream _min 15 mm flusso refrigerante A refrigerant flow sezione tubo aspirazione uscita evaporatore suction pipe section evaporator outlet fascia elastica A elastic band isolante termico thermal insulating Fig 4 h NOTE avoid using a socket for below zero showcases or cold rooms where ice frequently forms on the pipe and may damage the socket 4 2 Evaporation pressure transducer The pressure transducer must be installed near the temperature probe on the top of the pipe It can be positioned away from the point of temperature measurement only if the section of pipe that separates the two probes does not contain devices that alter the pressure heat exchangers flow indicators valves etc Depending on the type of controller two types of pressure transducer can be used which differ as regards the output signal 0 5 4 5 V ratiometric type SPKT RO per Evd400 MasterCase 1 and 2 mpxPRO alimentazione X supply OUTPUT 0 5 4 5 V Fig 4 4 20mA type SPKT CO for Evd200 300 MasterCase 2 mpxPRO non utilizzato not used 111620 UNF OUTPUT 4 20 mA Fig 4 1 Code 030220811 rel 1 0 26 04 2007 12 in
17. d of normal temperature control by temporarily lowering the utility set point so as to better check the trend in the superheat e check a complete set of parameters in all unit operating conditions start after extended stop temperature control active defrost changes in cooling capacity Code 030220811 rel 1 0 26 04 2007 22 As concerns the control parameters the following general indications can be used as a guide Proportional gain from 3 to 30 Increasing the proportional gain K increases the reaction speed of the valve and is recommended if the system Is particularly perturbed or to make superheat control faster If high gt 20 may cause swings and instability Integration time from 40 to 400 sec Increasing the integration time Ti improves stability but makes the valve slower in reaching the superheat set point If lowered lt 40 sec generates swings and instability If the system is already perturbed high values gt 150 sec are suggested so as to avoid creating further disturbance Derivative time from 0 to 10 sec Increasing the derivative time Td improves the reactivity of the valve in particular in perturbed systems reducing the amplitude of swings in the superheat If high gt 10 sec may in turn generate excess reactivity and consequently Swings Protector thresholds The thresholds used for the 4 protectors should be set based on the features of the system being controlled All are expressed as temperatures
18. d prot integration time po 20 Tab 8 a Recommended parameters for SHOWCASE and COLD ROOM applications RETAIL UN oO G oO oO Multiplexed showcases cold rooms with subcritical CO er CCT m 5 Condenser on R404a for subcritical CO REFRIGERATION WITH SUBCRITICAL CO N emi el ton omme 0 Me O MOP prot threshold 0 MOP prot maximum MOP HiTsurr superheated gas temperature T 30 0 limit MOP Delay MOP prot activation delay at EN 0 start sec HiTcond Ti HiTcond prot integration time Tab 8 b Recommended parameters for SHOWCASE and COLD ROOM applications WITH SUBCRITICAL CO The HiTcond protection can only be enabled if the condenser probe is connected to the driver and its value is sent via LAN Otherwise the Integration time must be set to 0 S Only to be used with electronic valves for superheat control on plate exchangers with R404a for cascade condensers of compressor racks with subcritical CO Code 030220811 rel 1 0 26 04 2007 20 control Plate Tube bundle Finned coil evaporator evaporator evaporator ECON I oe Ta E 3 gt LOP Ti LOP prot integration time AIR CONDITIONERS CHILLERS MOP prot threshold i PROTECTOR MOP Ti MOP prot integration time s MOP prot maximum MOP HiTsurr superheated gas temperature kg limit MOP Delay prot activation delay at a HiTcond HiTcond prot threshold HiTcond Ti
19. e th Varano a the resistance of the windings using an ordinary tester EN SL or incorrectly The resistance of both should be around 36 ohms Otherwise multiplexe replace the stator Finally check the electrical connections of the showcases only cable to the driver see paragraph 5 1 Use manual control after start up to completely open the valve If Valve stuck closed the superheat remains high check the electrical connections and or replace the valve Check the pLAN tLAN connections Check that the pCO The showcase does Stade U DEN RN application connected to the driver where featured correctly not reach the set configuration does not start control temperature and T and the valve remains closed manages the driver start signal Check that the driver is NOT in the position of the stand alone mode valve is always O The driver in stand alone Check the connection of the digital input Check that when the for multiplexed configuration does not start control control signal is sent that the input is closed correctly Check that showcases only and the valve remains closed the driver is in stand alone mode CAREL reserves the right to make modifications or changes to its products without prior warning Code 030220811 rel 1 0 26 04 2007 26 CAREL CAREL S p A Via dell Industria 11 35020 Brugine Padova Italy Tel 39 049 9716611 Fax 39 049 9716600 http www carel com e mail carel carel com
20. e and the superheat will generally be high or greater than the set point GE i If on the other hand the valve Is oversized the problems may involve system swings there may be wide variations In temperature pressure and superheat and consequently poor efficiency or alternatively there may be the return of liquid to the compressor 2 Installing the valve The electronic valve is installed using threaded or braze welded fittings depending on the codes e E2V S0 welded with stainless steel end outside diameter 10 mm e E2V SF welded with copper end outside diameter 12 mm e E2V SM welded with copper end outside diameter 16 mm LITI i a e E2V RB threaded with 3 8 side end 1 2 longitudinal end CL on To the side is the dimensional drawing of the E V valves the table below shows the dimensions of the various MELO ii meea RA models E lle fittings Fig 2 a A B C D E F mm in mm mm mm mm inch mm inch ch inch inch inch E2V So 127 0 lad 54 7 48 5 ID9 0D 10 ID 9 OD 10 Inox steel 10 10 5 0 2 90 2 15 1 98 in 0 35 ext 0 39 in 0 35 ext 0 39 K KC EKK Paan 121 9 68 7 49 7 43 4 ID 12 1 OD 14 ID 12 1 OD 14 1 12 mm op 4 79 2 70 195 171 in 047 out 0 55 in 0 47 out 0 55 KKK AR lic 123 9 70 7 51 7 45 4 ID 16 1 OD 18 ID 16 1 OD 18 16 16mmope 487 278 2 03 1 79 in 0 63 out 0 71 in 0 63 out 0 71
21. e noted that for applications with lower cooling capacities the use of an on off solenoid valve is recommended rather than the battery module considering the lower cost of the valves compared to the batteries Code 030220811 rel 1 0 26 04 2007 16 6 2 Controllers with built in driver Some specific CAREL controllers for showcases and cold rooms include the hardware and software for the management of electronic valves these are programmed in different ways Model Code Software user interface Hardware user interface Supervisor connection pLAN connection Control activation Type of pressure transducer Type of terminals Network address setting Range of network addresses Control as positioner Battery module MasterCase MasterCase 2 MGE000 020 MC200N0B10 MX20 3 or MX20 5 PC with PlantVisor PC with PlantVisor PST terminal with 3 or 6 PST terminal with 3 buttons buttons PGDO terminal with 4 rows YES YES Direct by built in controller Direct by built in controller Direct by built in controller 4 to 20 mA or ratiometric 4 to 20 mA or ratiometric Software via terminal Software via terminal 1 to 200 1 to 200 Tab 6 b It is obvious that these controllers do not require a LAN connection to the driver as this is built into the controller MPXPRO PC with PlantVisor IROOU terminal with 4 buttons YES NO Plug in screw Software via terminal 1 to 200 NO EVBAT00300 The driver user interface
22. erheat and vice versa If the movement is reversed check the electrical connections The probe does not measure correct The superheat value ae values measured is incorrect Increase the superheat set point Initially set it to 12 C and check The superheat set point is too low that there is no longer return of liquid Then gradually reduce the set point always making sure there is no return of liquid If the superheat remains low for too long with the valve that is Slow to close increase the low superheat threshold and or decrease the low superheat integration time Initially set the threshold 3 C below the superheat set point with an integration time of 3 4 seconds Then gradually lower the low superheat threshold and increase the low superheat integration time checking that there is no return of liquid in any operating conditions Low superheat protection ineffective Liquid returns to the compressor during operating Disconnect the stator from the valve and the cable and measure eRe E SE the resistance of the windings using an ordinary tester comedy The resistance of both should be around 36 ohms Otherwise replace the stator Finally check the electrical connections of the cable to the driver see paragraph 5 1 Check if the superheating is always low lt 2 C with the valve Valve stuck open position permanently at 0 steps If so set the valve to manual control and close it completely If the superheat is always
23. ermostatic valve A low set point ensures better efficiency of the evaporator a lower air or water temperature and the temperature control set point is reached more easily Nonetheless instability may be created in the system with wider swings in the superheat and the return of liquid to the compressor A high set point ensures greater system stability and less or negligible swings in the superheat Nonetheless this may penalise the efficiency of the evaporator and prevent the temperature control set point from being reached 9 2 Control techniques The control parameters should only be changed from the recommended values chapter 8 when it is clear how these affect the control functions Considering as mentioned that a lower superheat set point causes swings but often ensures higher efficiency any changes to the parameter settings must be made with the objective of the achieving the best compromise between e _ lowering the utility control temperature or reaching the control set point more quickly e system stability e no return of liquid to the compressor In general to avoid control problems that cause damage to the compressor the following rules should be observed e only change the value of one parameter at a time e monitor the superheat trend the valve position and the utility control temperature for at least 10 30 min before deciding whether a change has improved or worsened the situation e if necessary extend the perio
24. f the relay Check that there are no bubbles in the sight glass upstream of the expansion valve Check that the subcooling is suitable greater than 5 C otherwise charge the circuit Check the movement of the valve by placing it in manual control and closing or opening it completely One complete opening must bring a decrease in the superheat and vice versa If the movement is reversed check the electrical connections Disconnect the stator from the valve and the cable and measure the resistance of the windings using an ordinary tester The resistance of both should be around 36 ohms Otherwise replace the stator Finally check the electrical connections of the cable to the driver see paragraph 5 1 Use manual control after start up to completely open the valve If the superheat remains high check the electrical connections and or replace the valve 25 control control PROBLEM CAUSE SOLUTION The unit switches LOP protection disabled Set a LOP integration time greater than 0 sec off due to low Make sure that the LOP protection threshold is at the required pressure during saturated evaporation temperature between the rated control only for LOP protection ineffective evaporation temperature of the unit and the corresponding units with temperature at the calibration of the low pressure switch and compressor on decrease the value of the LOP integration time board enod boded Check that the solenoid opens correc
25. g set point As control is PID Proportional Integral Derivative hereinafter the control algorithm will simply be called PID The PID is the sum of three distinct actions Proportional action P defined by parameter K proportional gain The proportional action opens or closes the valve by K steps whenever the superheat increases or decreases by 1 C Consequently the higher the value of K the faster the reaction of the valve to variations in the superheat The proportional action is fundamental as it affects the speed of response of the valve in general however it only considers the variation in the superheat and not the corresponding set point Therefore if the superheat does not vary significantly the valve will essentially remain steady and the superheat set point may not be reached Integral action I defined by parameter Ti integration time sec The integral action is related to time and makes the valve move in proportion to how far the superheat temperature Is away from the set point The higher the difference the more intense the integral action the lower the integration time TI the more intense be the integral action The integral action is required to ensure that the superheat reaches the set point Without this in fact the proportional action alone may stabilise the superheat at a value other than the set point Derivative action D defined by parameter Td derivative time sec The derivative action i
26. ing when the start control signal is sent from digital input PLAN tLAN or built in controller 2 the valve position constantly follows the superheat value opening or closing when the superheat increases or decreases 3 the refrigerant flows through the evaporator and the air or water temperature of the controlled utility moves towards the set point If the previous checks fail check the electrical connections the water circuit and the parameter settings See the following chapter on troubleshooting During control the following also need to be checked 4 the superheat Is always around the set point with swings that depending on how perturbed the system IS vary between 0 2 C and 4 C 5 the valve position always continues to follow the superheat increasing or decreasing around the working position 6 The controlled utility reaches the set point or the required air or water temperature 7 There is no return of liquid to the compressor If the previous checks fail refer again to the following chapter on troubleshooting 9 1 Selecting the superheat set point The superheat set point should be selected based on the recommended value described in chapter 8 and set as established by the design specifications of the controlled utility Nonetheless it should be stressed that the corresponding parameter can be modified at any time so as to change the control reference exactly in the same way as calibrating a traditional th
27. kly to open the valve when the evaporation temperature is too low to prevent the compressor from stopping due to low pressure The MOP protection acts moderately to close the valve and limit the evaporation temperature if this reaches excessive values so as to prevent the compressor from stopping due to thermal overload The HITCond protection can only be enabled if the controller measures the condensing pressure temperature acts moderately to close the valve if the condensing temperature reaches excessive values to prevent the compressor from stopping due to high pressure Each of these protectors features a threshold and an integration time the activation speed of the protectors is higher the lower the corresponding integration time The threshold on the other hand is defined depending on the compressor and the application The use of the protectors is recommended however this is at the user s discretion 8 3 Recommended parameters Below are the most suitable values of the parameters for each application and specifically for CAREL valves If valves made by other manufacturers are used the same recommended parameters can be used Initially modifying the Proportional gain based on the maximum number of control steps for the valve installed Example of adapting the proportional gain for the different valves Reference CAREL E2V 480 maximum control steps proportional gain 5 gt Sporlan SEI 1 1596 steps proportional gai
28. linearly to 0 and 100 opening When the driver works in this mode control of the valve and all the alarms are disabled Model EVD200 EVD300 pr tLAN EVD400 pLAN EVD400 RS485 Code EVDO000200 EVDO000300 EVD0000400 430 430 EVD0000410 440 EVD0000410 440 440 EVD0000420 450 Software user SR controller PC with ne PC with EVD4 Ul PC with EVD4 UI interface via pLAN PlantVisor P iL ke pCO via pLAN or PlantVisor Hardware bas 5 signal LEDs 5 signal LEDs NO NO interface supervisor Connectable in NO pLAN uE From pLAN From digital From tLAN pCO Control activation pCO 10 From pLAN pCO From digital input Type of pressure 4 to 20 mA 4 to 20 mA Ratiometric Ratiometric Ratiometric transducer Type of terminals Plug in Minifit Plug in Minifit Plug in Minifit s Hardware Software with Software with Software with ao aus i with EVD4 Ul Key EVD4_UI Key EVD4 Ul Key 8 microswitches EVDKEY0001 EVDKEY0001 EVDKEY0001 addresses Control as 4 20 mA or 0 10V 4 20mAor0 10V 4 20 mA or 0 10 V positioner Battery module EVBAT00100 EVBAT00100 EVBAT00300 EVBAT00300 EVBAT00300 Tab 6 a Models EVD0000400 EVD0000410 EVD0000420 can be configured to control different types of valves with stepper motor CAREL Sporlan Alco Danfoss Models EVD0000430 EVD0000440 EVD0000450 on the other hand are pre configured for CAREL valves only All models of EVD400 are available in multiple packages 10 pcs code EVD00004 1 Finally it should b
29. n 5 x 1596 480 16 Alco EX 5 750 steps proportional gain 5 x 750 480 8 The following tables also show a specific category called perturbed system Perturbed system defines a refrigeration unit in which the condensing pressure and or the refrigerant charge vary continuously and rapidly The superheat can also vary when the subcooling Is low or null critical refrigerant charge and the superheat set point is less than the value specified in the tables or low in general In a perturbed system the control variables superheat and evaporation temperature vary significantly however not due to the electronic valve which consequently must have more intense reactions to be able to keep the superheat around the set point Obviously the more perturbed the system the lower the probability of achieving a stable superheat Code 030220215 rel 1 4 25 04 2007 19 control ul Perturbed SHOWCASES COLD ROOMS Multiplexed compressor system on board on 0 PID om Taar es IRE at Juice 0 45 C LT Gal VI N 5 oO LOP Ti LOP prot integration time EA KS S S 5 15 C LT 15 C LT 15 C L7 MOP prot threshold 5 C NT 45 C ND 45 C NT S S C S 30 PRIETO MOPTI MOP prot integration time ps oa mo MOP prot maximum MOP HiTsurr superheated gas temperature 20 30 30 limit MOP Delay ER prot activation delay at ps e fw HiTcond Ti HiTcon
30. on temperature gives the superheat 3 1 Ideal position of the probes The ideal position for both probes is immediately at the evaporator outlet so as to be able to measure the effective refrigerant superheat eS AS E V Temp misura del surriscaldamento Press on superheat detection VSLLIDIIPALIZILILILILELIEIEIELIEELIEIZIEELLILIELIIIIILILILILILILILILIZIZZIZIZ Rubinetto a sfera opzionale Ball valve optional Temp misura del surriscaldamento W nm gt gt lt superheat detection Filtro Valvola solenoide Rubinetto a sfera opzionale Filter Solenoid valve Ball valve optional Fig 3 a Code 030220215 rel 1 4 25 04 2007 9 installation 3 2 Positioning with external pressure probe If there is the need to simplify the inspection and replacement of the pressure probe or to share the reading of the probe between master and slave utilities for multiplexed showcases with controllers that support this function the pressure probe can be installed outside of the showcase and away from the temperature probe This is possible only where there is no device that alters the pressure creating a pressure drop in the section that separates the two probes in particular the liquid gas exchanger that is often installed downstream of the evaporator Rubinetto a sfera opzionale Ball valve optional bo os Filtro Valvola solenoide Rubinetto a sfera opzionale Filter Solenoid valve Ball
31. ormation provided on the instruction sheet supplied in the packaging Connect the 24 V power supply the optional battery module the optional communication LAN pLAN tLAN or RS485 the alarm relay if used the digital input for enabling control if used and finally the temperature and pressure probes e temperature probe 2 wires indifferent polarity e ratiometric pressure probe SPKT RO 3 wires earth green 5 Vdc power supply black and signal white e 4 20mA pressure probe SPKT CO 2 wires 2 28 Vdc power supply black and signal white MasterCase EVD200 300 a E L L o S S LL ba Q i Cei Ban BEN o Ol d 5 los z 2 Y h A i a verde 2S 1 3 gt green lasciare sconnesso il filo verde let green wire unconnected Fig 54 Fig 5 If the driver is used with the RS485 serial or pLAN address setting via hardware with microswitches binary logic as for the EVD200 and EVD300 refer to the corresponding instruction sheets to set the communication address To make the configuration lift the front panel that houses the signal LEDs and set the position of microswitches from 1 to 5 making sure not to damage the flat connection cable to the main printed circuit 5 3 Battery module connection for closing the valve The EVBAT00 00 battery modules are electronic devices that guarantee temporary power supply to the EVD200 300 400 drivers and the built in driver on the m
32. ot drop hit or shake the device as the internal circuits and mechanisms may be irreparably damaged Do not use corrosive chemicals solvents or aggressive detergents to clean the device Do not use the product for applications other than those specified in the technical manual All of the above suggestions likewise apply to the controllers serial boards programming keys or any other accessory in the CAREL product portfolio CAREL adopts a policy of continual development Consequently CAREL reserves the right to make changes and improvements to any product described in this document without prior warning The technical specifications shown in the manual may be changed without prior warning The liability of CAREL in relation to its products is specified in the CAREL general contract conditions available on the website www carel com and or by specific agreements with customers specifically to the extent where allowed by applicable legislation in no case will CAREL its employees or subsidiaries be liable for any lost earnings or sales losses of data and information costs of replacement goods or services damage to things or people downtime or any direct indirect incidental actual punitive exemplary special or consequential damage of any kind whatsoever whether contractual extra contractual or due to negligence or any other liabilities deriving from the installation use or impossibility to use the product even if CAREL or its subsidi
33. pipe to the face of a clock the probe must be positioned at 12 o clock for pipes with a diameter less than 22 mm and at 4 30 or 7 30 for pipes with a diameter greater than or equal to 22 mm Fig 4 d All precautions must be taken to maximise the thermal coupling between the pipe and probe spreading conductive paste on the point of contact between the probe and the pipe fastening the probe with a clamp included with the NICE The probe cable must be looped in the immediate vicinity of the probe and then secured by elastic band this will prevent significant vartations in temperature such as those that occur during the defrost cycles that may damage the cable connection to the probe Finally the pipe probe assembly should first be covered with aluminium tape and then with insulating material No types of adhesive should be used to avoid ruining the plastic material used to make the probe or the cable fascetta di fissaggio tubo aspirazione fastening band uscita evaporatore suction pipe evaporator outlet fascia elastica elastic band ag conductive cream Fig 4 Code 030220215 rel 1 4 25 04 2007 11 installation In air conditioners above zero chillers where better measurement precision and a faster response Is required the NTC WF probe should be used with installation in a socket Good thermal coupling must be guaranteed between the socket and the probe applying abundant conductive p
34. pxPRO chapter 6 Powered by a backup battery these provide continuous voltage to the driver for the time required to completely close the electronic valve in the event of mains power failures while during normal operation the module makes sure the battery Is recharged Battery modules for EVD200 and EVD300 e EVBAT00100 complete kit including the power supply battery charger 3 x 6V 1 2 Ah batteries and the set of connection cables and can supply just one valve e EVBATBOXO00 support for 3 batteries with DIN rail mounting e 6436503AXX spare battery Battery modules for EVD400 and mpxPRO e EVBAT00300 complete kit including the power supply battery charger 2 x 6V 1 2 Ah batteries and the set of connection cables and can supply two valves at the same time e EVBATBOX10 support for 2 batteries with DIN rail mounting e 6436503AXX spare battery e 59C545A003 spare set of connection cables e EVBATO0200 spare power supply battery charger module Below are the connection diagrams of the two modules to the corresponding drivers and the dimensional drawings of the battery supports Code 030220811 rel 1 0 26 04 2007 14 installation fusibile 2A EVBAT00100 Mn 6436503AXX 6436503AXX fusibile 2A fuse 24 59C545A003 3 x 6436503AXX 24 Vac Vde fino a 2 EVD400 Up to 2 EVD400 Fig 5 8 Connettore lato ingresso fili Connector wires input side Fig 5 h 45 82 8 5
35. re AWG 18 22 cable 0 5 1 mm with an outside diameter of 4 6 mm to ensure the seal of the gasket on the cable gland and with a maximum length of 10 m Note the colours used for the 4 poles so that when connecting the cable to the driver the numbering on the connector corresponds to the numbering on the driver Important contact no 4 on the connector is usually marked with the earth symbol In this case the Posizionare il connettore a solo in questa posizione Install the connector corresponding wire must not be earthed but rather connected just like the other wires to the corresponding only in this position terminal 4 on the driver C Finally connect the wires on the other end of the cable to the terminals on the driver carefully following the Fig 5 a instructions shown on the driver instruction sheet and observing the correct sequence of the colours If connected incorrectly the valve may not move or may move in reverse compared to the direction controlled by the driver statore morsettiera scatola connettore vite terminal blok connector case screw guarnizione gasket rondella iI CAREL CAREL washer E2VCON es Sateen vite di chiusura fastening screw Fig 5 b Ao Code 030220215 rel 1 4 25 04 2007 13 installation EVD400 bianco i FE white Fig 5 d 5 2 Probe and power supply connections Then complete the wiring of the driver following the inf
36. s related to the speed with which the superheat varies that is the instant by instant gradient of superheat variation This tends to contrast sudden variations in the superheat bringing forward the corrective action the effect is more intense the higher the time Td Valve opening at start up defines the percentage of opening that the valve moves to immediately before starting superheat control and should be set so as to be near the normal working position during control As an initial approximation it can be determined by calculating the ratio between the cooling capacity of the evaporator and the cooling capacity of the valve A 10 kW valve installed on a 5 kW evaporator will presumably operate at 50 opening The following parameters are involved e Valve opening at start up EVAP EEV capacity ratio Superheat set point PID proportional gain PID integration time PID derivative time Code 030220811 rel 1 0 26 04 2007 18 control 8 2 Protection function control parameters The software that manages the valve includes four protection functions LowSH protection low superheat LOP protection low evaporation temperature MOP protection high evaporation temperature HITCond protection high condensing temperature optional The LowSH protection acts quickly to close the valve in the event where the superheat Is too low to prevent the return of liquid to the compressor The LOP protection acts quic
37. stallation Both types of transducers use the SPKC 3 wire cable with Packard co moulded connector The ratiometric transducer uses all and three wires the 4 20 mA transducer only uses two the green wire is not used Each pressure transducer is supplied with a different range of measurement The parameters corresponding to the minimum and maximum pressure of the transducer used then need to be set The range that is most suitable for the application must be selected based on the following parameters e measurement precision improves if the range of evaporation pressure of the utility is in the centre of the range of measurement of the transducer e high pressure alarm to avoid the probe alarm being generated even when the utility is off for extended periods the pressure must reach lower values than the maximum measurable range e maximum limit each transducer has a maximum limit beyond which it may be damaged This must never be reached e explosion limit each transducer has an explosion limit beyond which the safety of the installation and the probe is not guaranteed This must never be reached In standard applications with HCFC and HFC refrigerants the following ranges are suggested ratiometric code SPKT0013RO from 1 to 9 3 barg 4 20 mA code SPKT0011C0 from 0 to 10 barg To improve the measurement precision transducers with a reduced range can be used e ratiometric code SPKTOO53RO from 1 to 4 2 barg e 4 20 mA code SPKT00
38. ther solutions can be used depending on the layout of the installation 2 3 Flow of refrigerant and spatial orientation of the valve The recommended direction of connection Figure 2 c sees the inlet on the side of the valve nonetheless the CAREL E V valves are bi directional up to the pressure differential specified on the instruction sheet Recommended direction Fig 2 d Important in no circumstances is upside down installation allowed that is with the stator facing downwards 2 4 Welding Unscrew the locking nut and remove the stator winding If necessary remove the connector if inserted Before starting welding wrap the body of the valve without the stator in a wet rag to avoid overheating the inside parts When finished welding replace the stator and tighten the valve stator locking nut Code 030220811 rel 1 0 26 04 2007 8 installation Observe the following warnings e do not let water or other foreign bodies fluids inside the valve this would make it impossible to completely clean the parts inside preferably use the side fitting on the valve for the refrigerant inlet do not install the valve with the stator facing downwards install a mechanical filter immediately upstream of the valve preferably install a sight glass upstream of the valve so as to be able to check correct flow during operation remove the stator from the valve body during the assembly for welded connections wrap the
39. tly check the electrical connections and the operation of the control relay Check that there are no bubbles of air in the liquid indicator Insufficient refrigerant upstream of the expansion valve Check that the subcooling is suitable greater than 5 C otherwise charge the circuit The valve is significantly undersized Replace the valve with a larger equivalent Disconnect the stator from the valve and the cable and measure the resistance of the windings using an ordinary tester The resistance of both should be around 36 ohms Otherwise replace the stator Finally check the electrical connections of the cable to the driver see paragraph 5 1 Stator broken or connected incorrectly Use manual control after start up to completely open the valve If Valve stuck closed the superheat remains high check the electrical connections and or replace the valve Check that the solenoid opens correctly check the electrical Solenoid blocked connections and the operation of the relay Check that there are no bubbles of air in the liquid indicator The showcase does Insufficient refrigerant upstream of the expansion valve Check that the subcooling is not reach the set suitable greater than 5 C otherwise charge the circuit temperature The valve is significantly undersized Replace the valve with a larger equivalent despite the value being opened to Disconnect the stator from the valve and the cable and measur
40. to purchase from the website www carel com Each CAREL product in relation to its advanced level of technology requires setup configuration programming commissioning to be able to operate in the best possible way for the specific application The failure to complete such operations which are required indicated in the user manual may cause the final product to malfunction CAREL accepts no liability in such cases Only qualified personnel may install or carry out technical service on the product The customer must only use the product in the manner described in the documentation relating to the product In addition to observing any further warnings described in this manual the following warnings must be heeded for all CAREL products e Preventthe electronic circuits from getting wet Rain humidity and all types of liquids or condensate contain corrosive minerals that may damage the electronic circuits In any case the product should be used or stored in environments that comply with the temperature and humidity limits specified in the manual e Do not install the device in particularly hot environments Too high temperatures may reduce the life of electronic devices damage them and deform or melt the plastic parts In any case the product should be used or stored in environments that comply with the temperature and humidity limits specified in the manual Do not attempt to open the device in any way other than described in the manual Do n
41. valve optional Fig 3 C 3 3 Positioning for reverse cycle heat pumps E V in bi directional operation In this case the pressure and temperature probes should be installed in the common suction branch low pressure in the refrigerant circuit Given the reduced distance between the point where the superheat is measured and the compressor the control settings and the superheat set point will need to be calibrated to safe values misura del surriscaldamento superheat detection Temp Press ramo a bassa pressione low pressure side valvola a 4 vie 4 way valve ramo ad alta pressione high pressure side Code 030220811 rel 1 0 26 04 2007 10 installation 4 Installing the probes s KK 4 1 Suction temperature probe 9 In The temperature probe must be selected based on the application Showcases cold rooms NTC HF with clamp or NTC HP ee Air conditioners chillers NTC WF preferably in a socket or NTC HF or NTC HP C en NTC HF 1 vista frontale l front view Fig 4 b NTC WF 04 contatto in gomma termoplastica contact zone in thermoplastic rubber eng 30 Fig 4 a Fig 4 C The position of this probe Is extremely Important as it determines the accuracy of the superheat value and the speed of response to variations in this The probe should be installed after the evaporator outlet in a straight and horizontal section Comparing the section of
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