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OPERATION & INSTALLATION MANUAL

1. 1 2 5 4 5 6 7 8 9 10 11 12 CONTAINED WITHIN MASTERWEIGH ENCLOSURE gt 2 2 gt O Yn 5 96 Zin lt lt 5 lt 4 IO gt de o a M FE GR a 0 DP 2 aa D ce 1 1 1 2 gt SS i Ww tO gt lt lt lt lt lt O jae a a 1 J J 1 1 98 J7 45 J5 J6 c J1 112131415 6 7186 9 10 112 13 14 112131415 1 92012 P P SHD DG Tin A A L L E E SHD GND TxD RxD SYSTEM STATUS AUTOZERO LIMIT ripen RS232 RS485 L LIN L2 GH ow BZ Se wo tea a 5 x gt n a O 2 2 D 6
2. 1100 840 110 0 84 0 1 0 FIXED PULLEY WITH FLANGE UNIT EXAMPLE 1 A E masiwa ADJUSTABLE PULLEY SCREW TAKE UP ENCLOSURE ENCLOSURE USING TAKE UP BEARING UNIT EXAMPLE 5 HOLES 912 0 y ey 3 7 A F SCREW Dp 24 222 50 980 A 7 ToRQUE ARM MOUNTED TO EQUIPMENT END ELEVATION TO TO MASTERWEIGH MASTERWEIGH ENCLOSURE ENCLOSURE al ROTARY SHAFT ENCODER ASSEMBLY MOUNTED DIRECTLY TO PULLEY FIXED PULLEY WITH PLUMMER BLOCK MOUNTING EXAMPLE 4 EXAMPLE 2 NOTES 1 THIS DRAWING SHOWS TYPICAL EXAMPLES ONLY 2 IS RECOMMENDED THAT THE ROTARY SHAFT ENCODER TACHO AND SPRING COUPLING BE SHROUDED PROTECT AGAINST MECHANICAL DAMAGE 3 EXAMPLE 3 BRACKET COUPLING BOLTS TO BE LOOSENED BEFORE ADJUSTING PULLEY TAKE
3. QUICK RELEASE LATCH 8 X 13 SLOT WITH PADLOCK FACILITY 2670 1057 159 0 625 203 0 807 M M 5 0 2 s Vo FRONT ELEVATION SIDE ELEVATION VIEW FROM REAR UNLESS OTHERWISE STATED DRAWN T BERNARDI WEB TECH AUSTRALIA PTY LTD DRAWING No BE WITHIN THE LIMITS SHOWN CHECKED 11 STREET OG PUNG 413 ATLA NUE SHT 2 Phone 61 7 3841 2844 Fax 61 7 3841 0005 51 01 ol up aove aove APPROVED CONTRACT S ue To uP To MASTERWEIGH 5 ENCLOSURE S PROJECT gt MOUNTING CENTRES amp i 52 MACHINING 01 02 03 05 10 SCALE 14 BA CARDANCEN 52 ENF EME FABRICATION 05 05 05 10 20 DO SCALE 101201 95 E IF IN DOUBT ALL DIMENSIONS MILLIMETRES and copyright property of WEB TECH AUSTRALIA Cre the confidential a ASSEMBLES 05 05 05 10 20 UNLESS OTHERWISE SPECIFIED are mut be alee lone copied for manufacturing tendering 2420 400 0 28 0 400 0
4. FRONT VIEW SIDE VIEW 1 ENCLOSURE MATERIAL 316 STAINLESS STEEL 270 0 2 ENCLOSURE RATING IP66 BOTTOM VIEW REVISIONS 9 11 05 ORIGINAL ISSUE UNLESS OTHERWISE STATED DRAWN L HARTLEY WEB TECH AUSTRALIA PTY LTD SIZE DRAWING No UNTOLERANCED DIMENSIONS NUMBER REV TO WITHIN THE LIMITS SHOWN CHECKED LH DING eke aon Phone 61 7 3841 2844 61 7 3841 0005 555 NOMINAL SIZE 50 150 300 1000 TITLE upto uP To 3 11 05 MASTERWEIGH 5 ELECTRONICS a WITH STAINLESS STEEL ENLOSURE MACHINING 01 02 03 05 10 SCALE NTS OPTION reader FABRICATION 05 05 05 10 20 DO NOT SCALE MWSSSGA IF IN DOUBT ALL DIMENSIONS IN MILLIMETRES Tiy devig or came hereon the conde ASSEMBLIES 505 05 05 10 20 ASK UNLESS OTHERWISE SPECIFIED muat Tot be loaned copied or used for monutacturing tendering Addendum ADDENDUM The following addenda are applicable to the equipment supplied for this contract Page 1 WEB TECH AUSTRALIA LTD Conveyor Designation Model Tacho Data
5. Zo HGH GH On CARE een E a SK ek lt lt lt J 1 J J J J8 97 J3 J5 J6 J1 11253 11213 1415 16171819 1011 12 13 114 112131415 ce P P SHD DG Tin A L L E E SHD GND TxD RxD Tx Com Rx SYSTEM STATUS AUTOZERO LIMIT 1 RS232 RS485 a lt 5 65 gt 92 2 lt jag PLE L TERCONNECTION CABLE TO BE REMOTE TOTALISER OR PLC INPUT z FOUR 4 CORE SCREENED SUPPLIED BY OTHERS 24VDC SUPPLY 12345678 NOTES 1 RATE OUTPUT IS ISOLATED 4 20 2 PULSE OUTPUT CAN BE 5VDC 24 VDC OR LOADCELL JUNCTION BOX REMOTE RATE METER VOLTAGE FREE CONTACTS LINK SELECTABLE OR PLC INPUT LOADCELL J BOX TERMINATION BOARD GREEN SIGNAL O SIGNAL LL SIGNAL WHITE SIGNAL SIGNAL L SIGNAL SCREEN lt O SCREEN lt SCREEN SCREEN 0 100 ENCODER TACHO RED EXCITE EXCITE ICTO EXCITE O SENSE O SENSE O SENSE BLACK EXCITE O EXCITE EXCITE SENSE O SENSE SENSE 5 0 LOADCELL LOADCELL 2 OR SHIELD 4 4 BLA
6. amp INSTALLATION MANUAL WTE21 E2400 Belt Scale with Masterweigh 5 Integrator Web Tech Australia Pty Ltd Head Office Sydney Office 11 Electronic Street PO Box 4006 Phone 02 9757 2296 EIGHT MILE PLAINS QLD 4113 EIGHT MILE PLAINS BRISBANE QLD 4113 Phone 07 3841 2844 AUSTRALIA Fax 07 3841 0005 Email webtech onaustralia com au wr Section 1 2 Web Tech Australia Pty Ltd TABLE OF CONTENTS Description Unpacking the Equipment Belt Scale Installation Guide Weighframe amp Electronics Installation Getting Started Belt Scale Maintenance Masterweigh 5 Operation Drawings Addendum Calibration Sheets Model WTE21 Scale Unpacking MODEL WTE21 UNPACKING EQUIPMENT PACKING 1 WEIGHFRAME The weighframe is shipped in a timber crate and is retained by bolts in the floor of the crate Remove these bolts before attempting to lift out the weighframe 2 ELECTRONICS The Masterweigh or Optimus electronics and enclosure are shipped in a separate cardboard box When removing the packing be sure to check for any documentation that may be supplied within the box 3 BELT SPEED SENSOR The belt speed sensor is normally shipped in the same box as the Masterweigh or Optimus electronics 4 CALIBRATION WEIGHTS The calibration weights if supplied are shipped in the same crate as the weighframe They are also bolted to the floor 5
7. INTERCONNECTION CABLE TO BE REMOTE TOTALISER OR PLC INPUT 2 FOUR 4 CORE SCREENED 6 SUPPLIED BY OTHERS 110 240 VAC 50 60 Hz 12345678 0 1 Amp 240V 0 2 Amp 120V NOTES 1 RATE OUTPUT IS ISOLATED 4 20 2 PULSE OUTPUT BE 5 0 24 VDC OR LOADCELL JUNCTION BOX REMOTE RATE METER VOLTAGE FREE CONTACTS LINK SELECTABLE OR PLC INPUT LOADCELL J BOX TERMINATION BOARD F GREEN SIGNAL SIGNAL SIGNAL SIGNAL O SIGNAL O SIGNAL SCREEN SCREEN lt O SCREEN SCREEN e SCREEN 0 100 ENCODER RED EXCITE TIO EXCITE 1 O EXCITE SENSE O SENSE O SENSE BLACK EXCITE EXCITE ESS O EXCITE SENSE Oy SENSE O SENSE OADCELL OADCELL 2 INDICATOR 5 Li LI L LI SHIELD 4 4 OR BLUE u OV GND 5 3 5v SUPPLY J 2 240 GREEN SIGNAL 1 1 F SHIELD LOAD CELL CONTAINED CABLE INTEGRAL 1 INTERCONNECTION CABLE 3 H SUPPLIED BY OTHERS SEANN 7 AUSTRALIA LTD size DRAWING No ACN 010 764 431 CHECKED 7008 ULE PLANS 4113 ASTRA Phone 61 7 3841 2644 61 7 384 0005 5 01 1 Y APPROVED TITLE _ CUSTOMER 5 ELECTRICAL CONNECTION DIAGRAM FOR ane TE SINGLE LOA
8. control output Provide serial communications for remote computers Provide Rate alarm outputs Provide batching facilities Most modern integrators are microprocessor based with computing power similar to a personal computer Each manufacturer engineers their own software which incorporates their own design philosophies Whilst all integrators may look similar at first glance the methods used by the various manufacturers to achieve the end result can vary significantly The current state of the art integrators are designed to make operation calibration easier for site personnel and great emphasis should be placed on the ease of use Many sites will prefer the Belt Scale supplier to carry out routine maintenance and calibration however in an emergency situation there is nothing worse than having to wade through a manual attempting to understand what a displayed code means Integrator Location The electronic integrator does not have to be located adjacent to the weighframe Some customers may wish to mount the integrator in a nearby motor control centre or in a control room Whilst this is possible the following points should be considered when selecting the location e The weighframe transducers produce very low voltage levels and therefore if long cables are used voltage drops may occur e The longer the cable run the greater the chance of picking up electrical noise on the cables BELT SCALE SELECTION AND INSTALL
9. Electronic Simulation Test Electronic Simulation tests are carried out without the use of weights material or chains When the test is initiated a shunt resistor is applied across the transducer input which creates an offset The value of the resistor is usually calculated to represent approximately 75 80 of maximum belt loading A test value is initially established at the time of commissioning which can then be used to check the repeatability of the system SCALE SELECTION AND INSTALLATION GUIDE CONT D This method of testing does not obviously take into account the belt effects or conveyor running conditions Web Tech provides this method of testing as a standard feature however we do not place great emphasis on it s use 4 CONVEYOR DESIGN Conveyors are designed to transport material from one location to another and not specifically for the benefit of a Belt Scale A Belt Scale is often an after thought and therefore the conveyor design may be less than ideal for accurate and repeatable results The following is asummary of recommended conveyor design Weighframe Location The weighframe should be located in a position where the belt tension and belt tension variations are minimal Generally speaking this location is at the tail end of the conveyor at the loading point However sufficient distance from the loading point should be provided to allow the material to be settled and be travelling at the same ve
10. calibration of the load cell span The test is 1659 E10 Os press run over a preset number of belt revolutions as in Menu 2 during which calibration weights 10 Seen only if span invalid or weigh chains are placed on the belt or weighframe A mass total is accumulated is invalid the course of the test This total is then TESS AAO CONUNUE compared with an expected or target weight and the span adjusted accordingly The display shows the currently stored load cell 1 Press Enter when at Menu Entry 4 to span value proceed 2 Atthis stage the belt span factor can be set manually by entering the desired span factor and pressing the Enter key If no value has been entered then no change is made to the stored value and the next level is entered Menu entry 4 Fixed weight calibrate span 222 1 3 Masterweigh 5 has been provided with two methods of span calibration Fixed Weight or Empirical Menu 5 Manual entry of Span Factor 0 000 or press Enter to continue 3 After initial calibration the user can by Span Cal Mode Fixed Weight toggling Fixed Weight to R Cal perform a Press Clear to Change Enter to accept calibration verification An explanation of this procedure follows this text 4 For initial calibration toggle this menu step to Fixed Weight by pressing the Clear C 120 8 t eons button if R Cal has been selected Current weight Enter target w
11. GETTING STARTED Now Masterweigh is counting the pulses coming from the tachometer and the elapsed time When the minimum time or one belt rev has occurred then the Enter key is again pressed when the mark on the belt passes the reference point Note Web Tech advises using 5 belt revolutions assuming that 5 belt revolutions take longer than 5 minutes and that full belt revolutions only are used The display will now change to the following The display will now look like the following Menu entry 3 Zero cal 0 010 mV 0 010 mV Press the Enter key to gain access to the menu The display will now look like the following Enter number of belt revolution 0 Pulses counted Time Manual entry of zero error 0 000 Or press Enter to continue Where yyyy number of pulses counted the elapsed time in seconds You should now enter the number of complete belt revolutions When the correct number of revolutions have been entered press Enter key and now Masterweigh will calculate the number of pulses per revolution and the display will change to the following At this point you could enter that value you found in Menu 8 earlier See Mechanical Tare If you don t remember don t worry as Masterweigh will calculate it later Note that the entry of data at this point only assists Masterweigh in finding an average zero and does NOT negate the requir
12. Software Version Contract No MENU FUNCTION MASTERWEIGH 5 SETTINGS 1 Parameter Setup Capacity Increments Size Pulse Time On Zero Reference Precision Reference 2 Pulses Programmed Pulses per Belt Revolution Revolution No of Belt Revs Zero Calibration Zero Calibration mV AutoZero Tracking mV 5 Emperical Span Empircal Span Null Level Null Level 7 Auto Zero Auto Zero Level Auto Zero Period Tracking Delay Time secs Fixed Weight 5 Target Weight Calibration Loadcell Input Dynamic No Load Dynamic with weights Tacho Frequency Tacho Frequency Hz Hz on VF Drive if appl Filter Constants Display Time Constant Rate O P Time Constant Tacho I P Time Constant Displayed Units tonnes hr kg hr kg min tons hr Ibs hr 0 1 2 Belt Speed Indicated Belt Speed m sec Hz on VF Drive if appl Indication Current Belt Length metres 5 1 Access Codes Operator Code Configuration Code 1 1 1 DESIGN DATA SERIES Conveyor Date CAL BARS 1 Max Nominated Conveyor Capacity t hr No Wt kg 2 Max Capacity in kg s 1 x 1900090 kg min 1 3 Measured Belt Speed m min 2 4 Max Load on Belt 2 3 kg m 3 5 Weigh Span metres 4 6 Loading across Weigh Span 4 x 5 kg 5 6 7 Effective Load Load cell See Fig 1 7 8 Length of Weigh Moment 0 305 yin table
13. If the Enter key is pressed during the test then the totalisation will be terminated with a mass total of zero The test can be aborted at any time by pressing the Abort key 8 The resulting mass total is displayed along with the number of belt revolutions counted Press the Enter key to calculate the new span calibration factor 9 The new derived loadcell span is displayed Press the Enter key to save this value as the new loadcell span Press the Abort key if this value is not to be stored 10 Should the span value calculated be outside the range 0 1 to 3000 then the Masterweigh will display a warning message Under these circumstances the new span will not be saved and the unit will revert to the value previously stored Calibration Methods MENU 4 1 Ideally conveyor belt scales should initially be calibrated using empirical data obtained from accurate static scales However in most situations this task is impossible to achieve but the fact remains that there is no substitution for data being input to Masterweigh 5 that has been derived from real material bearing down load cell the weighframe carriage at representative speeds 2 A calibration chain a device that rolls on top of the belt provides the next best method of calibration and check calibration It imparts load to the cells through the belt but can not simulate belt tensions as a fully loaded belt does 3 Static calibration weights are of
14. autozero tracking level selected the more sensitive Masterweigh is to detecting a relatively negative signal the appearance of the E during normal operation signifies to the operator that the weighframe should be inspected for mechanical damage or positional change The E can also appear if the conveyor belt is damaged with pieces missing etc GETTING STARTED 21 Scale BELT SCALE MAINTENANCE GUIDE ONGOING MAINTENANCE Many Belt Scale installations are ignored until a problem exists Like all equipment a minimum of maintenance will assist in providing long term reliability For multiple installations at the one site it may be worth contracting Web Tech to carry out the maintenance and regular calibrations These visits can also be used to provide basic training for the site personnel in the event of an emergency breakdown situation These site visits are normally scheduled at three monthly intervals The following work should be carried out on a regular weekly basis Clean down of build up on weighframe and removal of spillage Inspection and cleaning of idler rolls Zero calibrations Inspect belt tracking Inspect belt wear 9 9 NOTE The Zero calibrations can be AutoZero initiated which only requires belt to be run empty for the calibration period The following work can be carried out less frequently 3 monthly Span calibrations Check cabling and junction boxes The follow
15. indicating when an increment in Masterweigh s total has occurred 1 An Internally Generated 5VDC Pulse 2 An Internally Generated 28VDC Pulse 3 Contact closure from internal relay providing voltage free contacts Which of these options is used can be selected from links LK6 LK7 and 9 as shown in the USER CONFIGURATION section The pulse duration is adjustable in Menu 1 One pulse is output each time the least significant mass total digit displayed is incremented by 1 count A minimum of 20 milliseconds is guaranteed between pulses thereby providing a maximum pulse rate of 25 pulses per second 20 milliseconds on plus 20 milliseconds off The internal 5V supply is regulated to 5V It is not isolated from ground External load resistance should not be lower than 50 ohms The internal 28V is unregulated and may vary over the range 25 35V It is isolated from ground to allow configuration of fully isolated pulse output This 28V supply is shared with the 4 20mA analogue loop output and is rated at 400mA continuous maximum current The contact closure is completely isolated and is rated at 32V maximum and 500mA maximum It must not be used for 110V or 240V operation All pulse outputs are protected by 2 of 500 fast blow fuses F2 and F3 Analog Output The Masterweigh provides one analog output channel The output operates over 4 20 range and provides a resolution of better
16. 1000 Hz Belt speed sensors should not be connected to the drive pulley as any slippage between the drive pulley and conveyor belt will not be measured A second type of belt speed sensor involves mounting a sprocket at the end of a conveyor roll and sensing it s rotational speed with the use of a Magnetic Pick up The Magnetic Pick up counts the number of sprocket teeth that pass by a sensing element and therefore produces a frequency proportional to the speed This system is not normally used on applications where the conveyor rolls are subject to material build up as this will change the diameter of the roll and therefore the indicated belt soeed However on some applications where the idler rolls appear to be carrying build up closer inspection will show that the area of idler roll in contact with the belt remains clean The advantages of using the idler roll sprocket type of sensor is that they are relatively simple and robust and can be situated close to the weighframe When installed close to the weighframe the belt speed being measured is the actual belt speed at the weighframe A third type of system still popular with some manufacturers customers is the use of a pivoted trailing arm with a wheel in contact with the return belt The wheel is attached to a rotary sensor similar to that used with the tail pulley method The disadvantages of this method are The wheel is prone to bounce when disturbance in the
17. 844 8 800 32in 1 H TORQUE TUBE 900mm 36in 1 1000mm 40in 1 1050mm 42in 1 B A 2 8328 s a gt D E 6 Ae pel NORMAL DIRECTION OF CONVEYOR BELT TRAVEL 11 gt CONVEYOR IDLER ro G a WELD IDLER FRAME TO I Wek gt CALIBRATION BAR ANGLE BRACKET SUPPLIED POSITION 5 gt A M o H N H 5 LOADCELL EXISTING CONVEYOR STRUCTURE 1486 SECTION a SECTION SCALE 1 5 ke SCALE 1 5 YX UNLESS OTHERWISE STATED DRAWN TONY BERNARDI AUSTRALIA PTY LTD SIZE DRAWING No UNTOLERANCED DIMENSIONS BE WITHIN THE LIMITS SHOWN CHECKED PLING URED oe Phone 61 7 3841 2844 61 7 3841 0005 2 2 OR MODEL WTE21 CONVEYOR a 8 ooo DATE APP D 170 _ Slow BELT SCALE STRAIN DYNE LOADCELL nz La MACHINING 01 02 03 05 10 SCALE 1 5 cae SCALE WEIGHFRAME GENERAL ARRANGEMENT 05 05 055 1 2 2 IF IN DOUBT ALL DIMENSIONS IN MILLIMETRES tnd copyright property of MOTEC AUSTRALIA PTY LOD wen the confidential aS ASSEMBLIES 0 5 05 05 10 20 ASK UNLESS OTHERWIS
18. GUARDS 5 Idlers min 5 Idlers min External Influences such as wind can effect the accuracy of the Belt Scale Wind guards should be installed for at least 5 idlers either side of the weighframe where necessary SINGLE IDLER PIVOTED WEIGHFRAME TRANSDUCER LOADCELL DUAL IDLER PIVOTED WEIGHFRAME TRANSDUCER LOADCELL SINGLE IDLER FULLY FLOATING WEIGHFRAME MULTI IDLER FULLY FLOATING WEIGHFRAME VARIOUS WEIGHFRAME CONFIGURATIONS BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D 5 WHICH MODEL BELT SCALE Most Belt Scale manufacturers can supply a number of different model weighframes and electronics Some models may appear to duplicate each other in regard to accuracy specifications and general features For example two different model weighframes may be specified at an accuracy of 0 5 However one model may be designed for medium duties with relatively light belt loadings and the other for heavy duty applications with high belt loadings When you examine the construction of the weighframe will it stand up to the duty The accuracy of the system will be determined by the weighframe type as the same model electronics will normally be used regardless of the accuracy requirements More than one model electronics may be available however this is generally because they offer various options When specifying a desired accuracy for the Belt Scale system the application should
19. UP TO ALLOW FOR THE REALIGNMENT OF THE SHAFT ENCODER RETIGHTENED FOLLOWING ADJUSTMENT 3 1 TORQUE ARM WEB TECH SUPPLY 2 1 ROTARY SHAFT ENCODER TACHO WEB TECH SUPPLY 1 1 5 8 S S SPRING COUPLING 5 5 SUPPLY ITEM QTY PART NUMBER DRAWING 51 7 DESCRIPTION LENGTH MAT SPEC WEIGHT REMARKS lt DRAW AUSTRALIA LTD SIZE DRAWING No 9 a UNTOLERANCED DIMENSIONS re i i A NUMBER SHT REV a ae WITHIN THE LIMITS SHOWN CHECKED 11 ELECTRONICS STREET EIGHT MILE PLAINS QUEENSLAND 4113 AUSTRALIA 2 RG S 1 PO hore 81 7 3841 2844 000S 5013 oo 5 mE TYPICAL INSTALLATIONS OF ROTARY Aa 5 Bu a ATE TIA JEC 2 Shae SHAFT ENCODER IN CONJUNCTION PRSS 9282 gt lt MACHINING 01 0 2 203 205 1 0 NTS CAD FILE ota AT SAA WITH CONVEYOR BELT SCALES 65861 ziS FABRICATION 05 05 05 1 10 20 Ka DO NOT SCALE 10230 ee IF IN DOUBT ALL DIMENSIONS IN MILLIMETRES os E ee en ane ASK UNLESS OTHERWISE SEECINED a 318 0 1257
20. Whilst the mathematics used by the Belt Scale electronics may appear to be relatively simple the tasks required of the electronics are more complex Not only must the electronics be capable of receiving and processing the signals from the weighing mechanism and belt speed travel device it must also be capable of the following Display Rate and Total readings BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Provide stable power supplies to the weighing and belt speed travel elements Provide analogue and digital outputs for remote equipment Provide Automatic Zero and Span calibration facilities Provide serial communications for remote computers Carry out AutoZero routines when the belt is empty Provide alarm functions Provide control functions Interface with the operator measurement the weight the conveyor belt and belt speed travel also present some physical problems which must be overcome The accuracy of the weight measurement is dependant on a number of factors such as belt tension belt construction weighframe location troughing angle and material loading The degree of accuracy and ways of improving the accuracy are discussed in further detail in the following sections 3 BELT SCALE COMPONENTS Basically Belt Scales consist of four main components The main components are i Weighframe and associated weigh idlers Belt speed travel sensor iii E
21. be investigated thoroughly Like most equipment the higher the accuracy specified the more expensive the system will be Belt Scale accuracy depends on a number of factors such as belt tension belt type location and belt loadings However they are usually categorised into one of three groups SINGLE IDLER General purpose process scales with typical accuracies in the order of 1 10 3 DUAL IDLER Inventory purpose scales with typical accuracy of 0 5 MULTI IDLER High precision systems such as shiploaders and scales for payment purposes Accuracy typically 0 25 However in some applications it may be necessary to use a four idler weighframe to achieve 1 accuracy On other applications a single idler weighframe may achieve 0 5 accuracies The Belt Scale supplier will require certain information regarding the application which should be detailed on their Application Data sheets It may be preferable to allow the supplier to review the data and advise what options are available in regard to the possible accuracy versus the costs rather than specifying the accuracy BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D 6 ONGOING MAINTENANCE Many Belt Scale installations are ignored until a problem exists Like all equipment a minimum of maintenance will assist in providing long term reliability For multiple installations at the one site it may be worth contracting the Belt Scale supplier to carry out the maintenance and reg
22. below 8 c c Torque tube and Load cell 9 9 Force on Load cell s Full Scale 7 x 8 kg 10 10 Calibration Bars Total kg 11 11 Length of Moment 0 457 in table below 12 c c Torque Tube and Weights 13 12 Force on Load cell s with Cal Bars 10 x 11 kg 14 13 Cal Bars as a of Max Capacity 12 9 x 100 15 14 Mass Rate with Cal 1 13 100 t hr 16 15 Tonnes per min with Cal Bars 14 60 t min 17 16 Time per Belt Revs secs 18 17 Time expressed in minutes 16 60 min 19 18 Target Weight for time period 15 17 tonnes 20 Load on cell s x z Item6 Total y 2 1 451 7 400 0 305 0 305 0 457 800 0 305 0 305 0 457 2400 0 219 0 991 1 219 1 374 2800 0 219 0 991 1 219 1 374 Fig 1 i 2 All dims from ofpivot T T Distance to centre of first idler dual idler only y Distance to load cell s centre 7 Distance tocentreof second idler a Distance Tocentreof Cal Wt
23. mass total and mass rate units Pressing the Enter key without entering a new unit number or pressing Abort will not change the currently displayed units 3 Press Menu and Enter to save MENU ENTRY 12 BELT SPEED INDICATION This entry displays the current belt speed in metres second or feet minute if the mass rate unit is in tons or lbs based on the total belt length in metres 1 Menu entry 12 Belt speed 3 10 metre second Belt load 75 015 kg metre Press E to continue Current belt total length 200 000m Enter new belt total length Enter measured speed metres min 0 000 Press E for belt length Calculated belt length 0 000 metres Press E to save otherwise Press A MENUS 11 amp 12 1 This entry shows the current calculated belt speed Press Enter once view the current belt loading 2 The current calculated belt loading will be displayed in the appropriate units Kg m or Lb ft depending on the mass units selected This belt loading is calculated from the current Mass Rate and belt speed 3 The current value for the belt length is shown If the belt length is known enter it here 4 the belt length is not known an accurate belt speed has been physically measured itself the Masterweigh can calculate the belt length Enter the measured belt speed in the units shown then press E to calculate the new belt length 5 If you e
24. of the transportation block Make sure that the lock nuts are loose before attempting to lift the striker bar Carefully bolt down the load cell using the four bolts and washers supplied Tighten the bolts alternatively to approximately 45Nm Now lower the striker bar into contact with the load cell by loosening anti clockwise the tare bolt until it is free of load 14 The cable from the load cell should be run in the steel conduit which is built into the weighframe A flexible conduit should be used to carry the load cell cable to the load cell junction box The junction box should be mounted on the outside of the conveyor stringer If the optional Web Tech load cell junction box is not used then a waterproof box should be used and all load cell wires terminated in a suitable connector strip Note Water ingress into the load cell junction box will cause inaccuracies and non linearity in the displayed Mass Rate and Total Only neutral cure Silastic should be used if sealant is required MECHANICAL INSTALLATION 21 Scale MECHANICAL INSTALLATION CONTD 15 Now the belt can be lowered and the belt take ups engaged It is a good idea to paint the idlers that are in the alignment zone a different colour from the non aligned idlers Signs should be posted warning maintenance personnel that the idlers in the alignment zone should not be adjusted or interfered with If the belt does not track properly and t
25. protected against most industrial electrical noise however problems with the mains supply encountered an external mains power filter should be used 21 Scale ELECTRICAL INSTALLATION CONTD Auto Zero Limit Alarm Terminal Strip 8 Masterweigh 5 is fitted with an Auto Zero Limit Alarm feature which can be used to alert operators that the Auto Zero Tracking has exceeded predetermined limits Terminal Com Relay Common Contact Terminal NO Relay Normally Open Contact Terminal NC Relay Normally Closed Contact System Status Alarm Terminal Strip J7 Masterweigh 5 is fitted with a System Status alarm which can be used to alert operators when an electronic problem has been detected or if the power to the electronics has been turned off The terminal designation is shown for the de energised condition In fault free circumstances the relay is energised Terminal Com Relay Common Contact Terminal NO Relay Normally Open Contact Terminal NC Relay Normally Closed Contact Pulse Output Terminal Strip J3 Masterweigh 5 provides a pulse output which can be used for remote totaliser PLC DCS The pulse output gives one pulse out each time the Main totaliser increments one count The type of pulse output can be selected as either SVDC 24VDC or Voltage Free Contacts by selecting the appropriate link configuration see elsewhere for details Terminal P Pulse Positive Te
26. shaft and the two grub screws located at both ends of the spring couplings c Electrical Connections Refer to Electrical connection drawings in the Drawing section NOTE The Tachometer must move with the tail pulley if screw take up is used Connect the tacho up as shown using Beldon 8771 or equivalent It is important to seal the junction box against water and to run the cable away from high voltage power cables ELECTRICAL INSTALLATION WTE21 Scale ELECTRICAL INSTALLATION CONTD Loosen the four screws on the junction box cover plate noting that they have retaining washers fro the screws and gasket The enclosed PCB can be removed by squeezing the nylon locks on the PCB stand offs in turn and pulling the board forward When Masterweigh has been connected and ready for commissioning it is advisable to observe the frequency of the tacho pulses arriving at Masterweigh displayed in Menu 9 The minimum frequency is 10Hz and the maximum 1000Hz The reading should be fairly stable if the conveyor is not surging or slipping Wild fluctuations generally indicate a mechanical problem with the tacho installation or conveyor drive Field Wiring Refer to Dwg WTMW5 01 1 WTMWS 01 7 All field wiring should be run away from any influence of high voltage and current cables Note If the field wiring is run in conduit make sure that the conduit termination is sealed so water cannot enter the Masterweigh enclosure f
27. should not so steep as to allow the material to be able to roll back on itself CONCAVE CURVES Tangent Point The minimum distance between the last weigh idler on weighframe and the tangent point of the curve should be no less than 20 metres and preferably 30 metres if possible CONVEX CURVES Tangent Point The minimum distance between the last weigh idler on weighframe and the tangent point of the curve should be no less than 6 metres WEIGHFRAME LOCATION CONCAVE AND CONVEX CURVES WEIGHSPAN Weighspan The amount of belt that the weighframe weighs Is called the welghspan The welgh idler s share half of the load with the adjacent fixed Idlers BELT LOADING When sizing conveyors the belt should be 75 80 volumetrically full CONVEYOR STIFFENING Weigh Idlers Fish Plates Install weighframe and at least one approach and one retreat idler on the same section of conveyor stringer Where this is not possible weld fish plate s between conveyor joints to prevant movement CONVEYOR SUPPORTS Weigh Area Ensure that conveyor structure is adequately supported within the Weigh Area Total deflection under full load should not exceed 0 25 TRAINING IDLERS 5 Idlers min 5 Idlers min Training Idlers It is preferable not to locate tracking idlers within the weighframe area Tracking idlers should be no closer than 5 Idler spacings from the weighframe WIND
28. system e Material Test Calibration Chain Train Static Calibration Weights e Electronic Simulation Material Test A material test is the best form of test that can be done The test involves collecting an amount of material that has passed over the Belt Scale and weighing it on an accurate static weighing system such as a weighbridge or bin weighing system Other methods of testing simulate material loading however only a material test duplicates the actual operating conditions of the conveyor With regard to the amount of material required for a test a general rule of thumb is a test of 10 minutes duration When considering the installation of a Belt Scale system a method of diverting material from the process should be investigated It is essential when carrying out a material test that it can be guaranteed that all of the material that has passed over the Belt Scale has been collected BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Calibration Chain Train Test A calibration chain train is a device that sits on the conveyor belt above the weighframe and approach and retreat idlers is restrained in position whilst the conveyor is run and simulates material loading A calibration chain consists of a series of interconnected steel rolls which is manufactured to represent approximately 80 of the maximum belt loading A calibration train is similar to a chain except that it consists of a series of interconnect
29. to the menus will be restricted Two four digit codes will have been entered see Menu 15 for details One code low level allows the code holder limited access to any data in the menus for inspection only The other code high level is needed for access to menus and to make modifications to constant start calibration sequences etc Note that no access is given if no code is entered If security codes have been activated on pressing the Menu key the computer waits for the four digit code If no attempt is made to enter a code then the display returns to MRMT format after 30 seconds an invalid code is detected the display returns to MRMT format immediately If a security code is detected then limited or complete access is gained to the menus as appropriate Once the menu format is exited the code will have to be re entered for further access ENTER KEY FUNCTIONS This key switches between the main display mode showing Total MRMT and the Menu mode AND J When Menu mode pressing or key once will go forward or backward one menu entry If either key is held down the menu changes will repeat at a rate of approx 5 per second When entering the data the key is the decimal point ABORT When the Menu mode and entering changes or new data this key enables the user to abort the changes and restore the existing entries The
30. 5 Operation MENU 8 LOADCELL INPUT Millivolts This entry displays the load cell input in millivolts The displayed value is unaffected by the load zero load calibration and zero tracking functions The entry also displays the excitation voltage as currently sensed by the Masterweigh It is displayed to the nearest volt only ie 10V is in the range 9 501 to 10 5V It is updated once every 3 minutes This display enables a user to confirm that the Masterweigh is correctly sensing the excitation voltage and thus that all links etc are correctly installed Incorrect excitation sensing will result in inaccurate and unstable mass rate measurements Access is also available to the output of the voltage to frequency converters Menu Entry 8 Loadcell 16mV Extin 10 2 V to F count xxxxx Press Enter to continue This facility is for technician s use only 1 Menu Entry 8 displays the load cell millivolt output and excitation voltage 2 Press E to access the current V to F output 3 Press E again to return to Menu Entry 8 MENU ENTRY 9 TACHO FREQUENCY This entry displays the current tacho frequency in hertz the input range is 5Hz to 1000Hz and switches between software or hardware inputs 1 Menu Entry 9 Tacho Frequency 50 005 Hertz 2 Tacho Source Hardware Press Clear to change Enter to accept 3 Tacho Source Simulated Press Clear to change Enter to accept 4 Tach
31. ATION GUIDE CONT D e Long distances between weighframe and integrator increases the time required when carrying out calibrations 15 the proposed area classified as Dust Ignition Proof or Hazardous It is Web Tech s belief that the best location for the integrator is adjacent to the weighframe where possible The output signals can be used to provide information to remote equipment The integrator should be mounted so that it is free from vibration not subject to direct sunlight and rain If installed outdoors it is suggested that rain sun hoods are used When selecting a Belt Scale system the following integrator features should be investigated Are the operation calibration functions displayed entered in plain English or in code form Is the circuit design truly digital or does it require potentiometer adjustments in it s setup Are service and fault finding functions available Does the integrator maintain it s accuracy over a wide temperature range typically 0 to 40 C Are the analogue and pulse outputs isolated Is the integrator enclosure suitable for the environment Does the system provide Automatic zero and calibration facilities Are the integrator outputs compatible with remote equipment Is the integrator supplied with filters on the mains input Can the integrator be easily serviced 44 4 K iv Calibration Device There are basically four methods that can be used to calibrate a Belt Scale
32. C and DC Note The excitation voltage regulators are overload and short circuit protected however short circuiting of the excitation output will interfere with normal operation of analog input circuitry and the RS232 interface Caution Application of an external voltage source to the excitation terminals may cause serious damage to the Masterweigh calibration adjustment of the Masterweigh analog inputs is required Gain and zero are automatically adjusted by the reference This automatic calibration 15 repeated once every 30 seconds whenever the Masterweigh is energised After energising the Masterweigh always allow a minimum of thirty 30 seconds for this automatic calibration to be performed before initiating a span or zero calibration sequence Note If Masterweigh has not been energised for some time allow 3 minutes before initiating the above Tacho Input and Supply a Electrical Characteristics The tacho input is designed to accept a voltage input of 2 5 to 50 volts peak and so will accept either a TTL or sinusoidal voltage input The input threshold voltage is 1 2 volts at the positive input with respect to the negative input The negative input is directly connected to the Masterweigh grounds Avoid earthing this input in the field as it will create ground loops The tacho input will not accept frequencies in excess of 800 Hz approx A regulated 5 volt supply is provided for energising
33. CK OR BLUE L OV GND 5 3 O 5v suppLY D 2 21 GREEN SIGNAL 1 1 SHELI LOAD CELL CONTAINED CABLE INTEGRAL L WEIGHFRAME INTERCONNECTION CABLE THREE 3 CORE SCREENED SUPPLIED BY OTHERS REVISIONS 7 8 07 ORIGINAL ISSUE DRAWN LH WEB TECH AUSTRALIA PTY LTD SIZE DRAWING ACN 010 764 431 APPROVED Phone 61 7 3841 2844 Fox 61 7 3841 0005 TMW5 01 4 A E ELECTRICAL CONNECTION DIAGRAM FOR ee SINGLE LOAD CELL BELT SCALES INCORP MASTERWEIGH 5 24VDC amp SPEED ENCODER FE DO NOT SCALE 5 01 7 IF IN DOUBT ALL DIMENSIONS MILLIMETRES and copyright propery of WEBTECH AUSTRALA PIY LID Se the confidential ASK UNLESS OTHERWISE SPECIFIED and muat not be loaned copied used for manufacturing tendering CLEARANCE HOLE 5 8 Q a F i 60 15 75 TYPICAL SHAFT EXTENSIO 7 WITH SPRING COUPLING 42
34. D CELL BELT SCALES INCORP gt T CAD FILE 50 NOT Scale MASTERWEIGH 5 amp CODER SPEED SENSOR IF IN DOUBT ALL DIMENSIONS IN MILLIMETRES and formation descriptive it hereon are the UNLESS OTHERWISE SPECIFIED ane must at be disclosed loaned copied or used for manufacturing tendering CONTAINED WITHIN MASTERWEIGH ENCLOSURE amp gt 172 oO Yn 5 gt gt zZz A 5 90 08 5 lt 2 gt ac 77 2 21 500 9 T a 5 amp D H 70 a 2 ac J J J 1 J 5 1 a gt 29 Br
35. E SPECIFIED and must not be disclosed loaned copied or used for menufacturing tendering 11 12 TYPICAL REPRESENTATION F INLINE CONVEYOR IDLERS IDLERS C2 THROUGH TO C2 ARE WEIGH QUALITY IDLERS EXISTING CONVEYOR STRINGER STRINGLINE REFERENCE THIS IS A NO STEP ZONE TYPICAL WELD 5 IDLER FRAME TO BRACKETS 5 TORQUE TUBE PLAN VIEW DIRECTION OF CONVEYOR BELT TRAVEL TYPICAL CALIBRATION BARS IN PLACE M AMOUNTS IN EACH POSITION TYPICAL REPRESENTATION OF OFFSET CONVEYOR IDLERS STRINGLINE REFERENCE 4 A 02 OFFSET CONVEYOR IDLER PACKING PLATE USED TO RAISE IDLER TO HEIGHT OF INLINE IDLER REFER NOTE 3 EXISTING CONVEYOR STRINGER SURFACE DETAIL STRINGLINE REFERENCE 120 Np SECTION REPRESENTATIONAL CROSS SECTION NTS OF EXISTING CONVEYOR STRINGER INLINE CONVEYOR IDLER EXISTING CONVEYOR STRINGER SURFACE TYPICAL WELD IDLER FRAME TO SUPPORT BRACKETS VIEW FROM SIE BE AWARE THAT THE RETURN TRAVEL OF THE CALIBRATION BARS EXISTING CONVEYOR STRINGER SURFACE DETAIL D BELT IS NOT TO FOUL THE INTERNAL FRAME OF THE BELT SCALE DEFLECTION IDLERS TO BE INSTALLED
36. IF THIS IS THE CASE LOADCELL JUNCTION BOX OPTIONAL SUPPLY E NOTES CONVEYOR IDLERS FROM C2 THRU TO C2 WEIGH QUALITY 6 OFF MUST BE INLINE IDLERS NOT OFFSET IDLERS CONVEYOR IDLERS FROM C3 THRU TO C3 MUST BE OUNTED AT RIGHT ANGLES TO THE DIRECTION OF BELT CENTRELINE DIMENSIONS SHOWN BETWEEN IDLERS MUST MAINTAINED TO A TOLERANCE OF 0 5mm ENERALLY IDLER HEIGHTS FOR OFFSET IDLERS IS LESS HAN THOSE FOR INLINE IDLERS PACKERS MAY BE USED LERS TO THE HEIGHT 0 LERS REFER DETAIL B 0mm GRADIENT PER METRE IS AN ALLOWABLE HT BETWEEN ROLL HEIGHTS IGNORE THIS NOTE F INLINE IDLERS ARE SOLELY USED 1 i a n gt m gt ROLLS 2 THRU TO 2 INCLUDING W2 THRU W1 ARE RILLED AND TAPPED M8 18 ROLLS IN TOTAL REFER DETAIL A ALL ROLLS MUST BE ADJUSTED TO STRINGLINE REFERENCE TO A OLERANCE OF 0 4mm 0 0 LEVEL CENTRE ROLLS ON C2 AND C2 IDLERS PRIOR TO ANY ADJUSTMENTS ENSURE ALL LOCKING NUTS ARE TIGHTENED AFTER ADJUSTMENTS ARE COMPLETED EIGHFRAME ORIENTATION AS SHOWN IS CORRECT FOR INCLINED AND HORIZONTAL CONVEYORS FOR DECLINED CONVEYORS REVERSE DIRECTION OF WEIGHFRAME HE LOAD CELL OR A LOAD CELL DUMMY OF EXACTLY THE SAME HEIGHT AS THE LOAD CELL MUST BE INSTALLED PRIOR TO ALIGNING IDLERS
37. OMETER ADJUSTMENTS Power Supply Bottom Board RV1 Used to adjust the load cell excitation used in conjunction with a digital meter or the Masterweigh when menu 8 been selected RV2 Used to boost the tachometer supply voltage when the voltage drops are evident at the tachometer due to a large separation between Masterweigh and the tachometer or due to Intrinsic Safety Barriers on the tachometer cables CPU PCB Top Board VR1 Adjusts the LCD display viewing angle so that the display can be easily read VR2 Used to span the analog output channel Use this potentiometer with a digital current meter in series with the output Use this potentiometer in conjunction with Menu 1 Sub Menu C final step to calibrate the analog output by setting the output to 20 000mA in the menu then adjusting the potentiometer until the current meter shows 20 000mA POTENTIOMETER ADJUSTMENTS 30 Masterweigh 5 Operation FIELD TERMINATIONS J1 Power supply input 1 L L1 240VAC 110VAC Active 2 N L2240VAC 110VAC Neutral 3 6 240VAC 110VAC Earth 8 Auto Zero Limit Alarm 1 COM Common contact 2 NO Normally open contact 3 NC Normally closed contact J7 System Status Relay 1 COM Common contract 2 NO Normally open contract 3 NC Normally closed contact J3 Load cell and tachometer inputs pulse counter and analog outptuts 1 P Pulse Counter Output Pulse Counter Output N
38. Press the Abort key The total achieved should be logged and future R Cal tests reference to it If the value recorded in subsequent tests exceeds 0 5 of the original value perform full calibration using weights etc Note Zero system prior to R Cal test MENU 4 Masterweigh 5 Operation MENU 5 EMPERICAL SPAN CALIBRATION This menu entry enables the entry of manual belt totalisations resultant recalculation of the load cell span To use this calibration facility it is necessary to weigh a quantity of material with the belt scales and then to accurately determine the actual mass of that material by independent means i e via a weighbridge The two totals are then entered and the Masterweigh computes the new span factor 1 Empirical calibration span 211 7 2 3 4 New span 205 6 previous 211 7 1 At menu Entry 5 press Enter to proceed 2 Enter the exact mass total as measured by the weighbridge Press Enter when the data is correct 3 Enter the mass total as measured by the weigher Press Enter 4 Press Enter to store the new span value as the load cell span calibration factor Press Abort if no update is required Press Menu and Enter to save Page 11 MENU 5 12 Masterweigh 5 Operation THIS PAGE INTENTIONALLY LEFT BLANK Masterweigh 5 Operation Page 13 MENU 6 NULL LEVEL This entry displays the level at which the load is considered to be zero Bel
39. Shd Shield DG Tacho Digital Ground Tin Tacho Signal In TE Tacho Excitation 5V 7 Analog output ve 8 Analog output ve 9 AG Analog ground 10 L Loadcell output ve 11 L Loadcell output ve 12 E Loadcell excitation ve 13 E Loadcell excitation ve 14 Shd Loadcell Shield FIELD TERMINATIONS J5 RS232 Communications Port 1 GND Ground 2 TXD Transmit 3 RXDReceive J6 RS485 Communications Port 1 TX Transmit 2 TX Transmit 3 COM Ground 4 RX Receive 5 RX Receive EEC DECLARATION OF CONFORMITY Directives Covered by this Declaration 89 336 EEC Electromagnetic Compatibility Directive amended by 92 31 EEC amp 93 68 EEC 72 23 EEC Low Voltage Equipment Directive amended by 93 68 EEC Product covered by this Declaration MASTERWEIGH 5 Variants included NONE The Products Identified Above comply with the protection requirements of the above EU Directives by meeting the following standards EN 50081 2 1994 Electromagnetic Compatibility Generic Emissions Standard Part 2 Industrial Environment EN 50082 2 1995 Electromagnetic Compatibility Generic Immunity Standard Part 2 Industrial Environment 61010 1 2 1995 AMD 8961 Safety requirements for electrical equipment for measurement control and laboratory use Part 1 General Requirements The CE Mark was first Applied in 1998 Verified that evidence of successful testing to the above standards has been viewe
40. U 16 Pressing Enter when report mode is Time based advances to 4 1 hour 0 hours Report every Enter new value Here the time based reporting period is displayed and may be modified The time period entered here will cause the Masterweigh 5 to automatically print a report via the serial port every time the period expires ie a report period of 4 hours will cause a report to be automatically printed at midnight 4 am 8 am noon 4 pm 8 pm etc Pressing enter here returns to step 1 above Pressing Enter when report mode is Total based advances to 5 100 tonnes 0 tonnes Report every Enter new value Here the total based reporting increment is displayed and may be modified The mass total increment entered here will cause the Masterweigh 5 to automatically print a report via the serial port every time the increment is added to the mass total ie a total increment of 2500 tonnes will cause a report to be automatically printed at 20000 tonnes 22500 tonnes 25000 tonnes 27500 tonnes etc Pressing Enter here returns to step 1 above The RS232 Parameter are Baud 19200 bps Data bit 8 bits Stop bit 2 bits Parity None Masterweigh 5 Operation Page 23 RECONFIGURING MASTERWEIGH 5 Under some circumstances Masterweigh s memory can be corrupted so that correct operation of the unit is not possible This condition can occur if Masterweigh has been subjected to severe electrical noise or spikes Thes
41. U 7 AUTO ZERO TRACKING Cont d 1 Menu Entry 7 press Enter to proceed 2 Enter the new autozero level in mass rate units and press the Enter key If the Enter key is pressed with no data entry then the stored value remains unchanged 3 Enter the period required in belt revolutions over which autozeroing occurs Note that the number of belt revolutions should be chosen such that the total zeroing period is of the order of 5 minutes or more This will ensure that accurate zero levels are produced Note that the actual zero level used by the Masterweigh will not be updated until a zeroing period has been completed If a new value is entered and the Enter key is pressed then that value is saved otherwise no update occurs 4 This step enables the qualifying delay time to be set Choose a time that will ensure that all material is off the belt The delay time commences when the mass rate falls below the minimum level set above 5 Step five allows the user to enter the value in mV below which it may considered that an invalid Autozero is taking place 6 Step six allows the user to enter the value in mV above which it may be considered that an invalid Autozero is taking place 7 Increase this factor if the letter is being encountered in the main display 8 The function of displaying the letter E can be switched on or off here by pressing the C button Page 15 MENU 7 16 Masterweigh
42. WEIGH IDLERS If weigh idlers have been supplied by Web Tech these will be packed on a separate pallet or skid STORAGE If the equipment is to be stored for a long period prior to installation we would suggest that the equipment be covered if in an outdoors situation EQUIPMENT DAMAGE If any equipment has been damaged in transit or some item s appears to be missing please contact Web Tech immediately Page 1 Web Tech Australia Pty Ltd BELT SCALE SELECTION AND INSTALLATION GUIDE BRISBANE SYDNEY W EB TECH BRISBANE Head Office SYDNEY OFFICE 11 Electronics Street Tel 61 29757 2296 Web page Eight Mile Plains QLD 4113 Australia Fax 61 2 9899 6585 Tel 61 7 3841 2844 Email webtech onaustralia com au Email webtech onaustralia com au MELBOURNE OFFICE Tel 61 3 9653 9260 Fax 61 3 9653 9699 Web Tech are manufacturers and designers webtech onaustralia com au Weigh belt feeders Conveyor belt scales Loss in Weight screw feeders Volumetric screw feeders Loss in Weight vibratory feeders Gain in Weight vibratory feeders Company Profile Web Tech is a wholly owned Australian company which specialise in the design and manufacture of continuous and static weighing systems for all facets of industry Web Tech have 15 years experience in the field of continuous weighing Web Tech s Head office and manufacturing works are located in Brisbane with a sales and service office in Sydn
43. a digital pulse generator This supply is rated at 200mA maximum and is overload and short circuit proof with fold back current limiting It may be necessary to briefly remove all load after removing a short circuit in order to reset the protection circuit Short circuiting of the tacho 5 volt supply will not affect the Masterweigh CPU operation Masterweigh is fitted with a potentiometer RV2 to adjust the tachometer s 5V rail if required Normally only used when the tacho supply drops to voltage where the tachometer ceases to work owing to significant voltage drop from long cable runs IS barriers or the like CAUTION Application of an_ external voltage source to the tacho supply terminals may cause damage to the Masterweigh b Frequency Selection The tacho generator should be selected and fitted to provide a frequency input to the Masterweigh within the range 5 to 1000 Hz to ensure compatibility amp accurate measurement The tachometer is normally selected for the user by the factory FACILITIES AVAILABLE Masterweigh 5 Operation Page 26 FACILITIES AVAILABLE Cont d Selection depends on rotational speed of the pick up pulley which in turn is supplied by the user Note that the tacho frequency has no affect on the rate at which the load cell signal is sampled Pulse Output The Masterweigh provides a pulse output for external accumulation of the mass total Masterweigh provides for three methods of
44. actured to weigh approximately 70 of the load that the weighframe will carry when the maximum flow rate as detailed in the client s data sheet is achieved With the belt stopped load all the calibration bars supplied onto the weighframe They should be placed centrally across the weigh arms and pushed hard up against the two stops Now set the weighfeeder running and advance Masterweigh to Menu 4 and enter that Menu by pressing the Enter key The display will change to the following Manual entry of span factor 0 000 Or press Enter to continue 21 Scale GETTING STARTED CONTD Normally with a new installation data would not be available at this stage as Masterweigh calculates this parameter however this entry is useful if span adjusting is required at a later date Press the Enter key and the display will change to the following 60 000 tonnes 0 000 tonnes Current weight Enter target weight Dealing with the target weight first When the system is purchased from Web Tech a set of data referring to the Belt Scale parameters accompany the delivery see back of manual for a sample After entering your target weight and pressing the Enter key the display will change to the following Press E to continue Mass rate mmmm Where mmmm the current mass rate prior to span adjustment On pressing E once again the display changes to the following To
45. ate a aaa Revs Where a aaa the zero error the number of revolutions completed Once Masterweigh has completed the test the display will change to the following To calculate new calibration Press E Mass total 7 777 Revs Where Z ZZZ the totalised value of the mass rate found during the routine x x the number of belt revolutions By pressing the Enter key at this point Masterweigh will calculate a new zero If something went wrong during the test e g material did accidentally get onto the belt pressing the Abort A key will cancel the test Following the pressing of the Enter key Masterweigh will display the zero as a voltage output from the load cell and once again give you the ability to cancel out the result Masterweigh will also cancel the tests if the results from that test fall outside preset limits See the section Load Zero Calibration in Masterweigh Operation GETTING STARTED Spanning Calibration There are three ways of calibrating spanning Masterweigh 1 By passing material over the belt weighing that material and then entering that value into Masterweigh via Menu 5 2 Using a weigh chain 3 Using supplied calibration bars This part of the manual will deal only with method 3 Refer to the calibration data sheet supplied with your system and the sample sheet at the rear of this manual The calibration bars supplied have been manuf
46. being returned during any period that the belt is considered to be running empty by the computer The window is set in this menu at step 5 amp 6 If the signal from the load cell falls outside these user preset levels then the Autozero limit alarm relay will energise Under some circumstances it may be necessary to increase the tolerance at which Masterweigh flags in the display that a negative loadcell excursions has taken place which is greater than the level set in the null x 2 The error is only flagged in the local display in the form of an E at the right hand side of the display where the 7 is normally shown MENU 7 Step 7 allows the user to increase the tolerance before displaying the E At step 8 the user can toggle the above function on or off depending on preferences Note Under normal running conditions negative loadcell excursions should not be occurring Check the weigh area for abnormalities 1 Menu Entry 7 Zero Track if greater than 20 0 for 5 revs 2 Auto Zero Level 20 00 tonnes hour 3 Auto zeroing period 5 revs Enter new period 0 4 Delay before auto zeroing 60secs Enter new Delay 0 5 Auto Zero Low Limit 0 000mV Enter new level 6 Auto Zero High Limit 0 000 Enter new level 0 000mV 7 Auto Zero Error Level 2 times Auto Zero Autozero Error Display is On Press Clear to Change Enter to accept Masterweigh 5 Operation MEN
47. cedures is to be found earlier in this manual Load Cell Input and Excitation The Masterweigh is designed to accept a load cell millivolt signal in the range 0 to 32 millivolts with a resolution of approximately 4 microvolts An on card voltage source provides excitation for the load cell This source can provide excitation for up to four 350 ohm load cells in parallel The excitation is not precisely controlled but is maintained within approximately 1 percent of the set value The Masterweigh monitors the excitation voltage and automatically compensates for any voltage change that may occur The excitation is adjustable over a wide range to enable optimum performance to be obtained from a wide variety of load cells Masterweigh be configured to provide either a positive excitation voltage referenced to ground unipolar or a plus minus bipolar voltage by configuration FACILITIES AVAILABLE of links The positive voltage is continuously adjustable from 4 to 12 volts The negative voltage is set at 12 volts The Masterweigh is factory set for a unipolar excitation of 10 volts Following adjustment of the excitation allow a minimum of 30 seconds for the Masterweigh to update its internal excitation reading before proceeding with calibration functions The approximate value of the excitation voltage sensed by the Masterweigh is displayed in Menu 8 This should match the voltage sensed at terminals J3 pi
48. ct with the stringlines it is likely that the lines will be deflected thus causing all further idlers to be misaligned The weigh idler rolls will have been fitted with grub screws and lock nuts These grub screws are to be used to lift the rolls into contact with the stringlines It should also be noted that a certain amount of profile adjustment can be made if careful use is made of the grub screws It is necessary to securely bolt down all the weighing idlers using the grub screws as the idler assembly will tend to be pulled away from stringlines when tightening the securing bolts Remember to tighten up the grub screw lock nut after the final adjustment has been made If the profile of the non weighing quality idlers needs to be altered then either weld support plates to the idlers shaft carrying slot if the particular rolls need lifting or grind out the slot if the rolls need to be lowered Web Tech will quote for the supply of new rolls with grub screws fitted to the shafts if this method is preferred Note The maximum vertical misalignment should be no more than 0 8mm 13 When the vertical alignment pitch and squareness of the idler is correct the transportation block can be removed and the working load cell installed To assist in removing the transportation block remove the calibration bars from the load arms if used Now lift the load arms by screwing the tare screw until the striker bar is just free
49. d Signed K Webster Authority Managing Director Attention The attention of the Specifier Purchaser Installer or User is drawn to special measures and limitations as to use if applicable which must be observed when this product is taken into service to maintain compliance with the above directives Details of these special measures and limitations are available on request and are also contained within the product manuals WEB TEGH CERTIFICATE NUMBER 5 001 7 1 2 4 5 6 7 8 10 11 12 MOUNTING SLOTS 106 106 14 WIDE x 30 LONG 27 27 27 27 i 450mm 18 756 544 500mm 20 806 594 H 600mm 24in 906 694 650mm 26in 956 744 750mm 30in 1056
50. dvances to 3 Configuration access code Enter access code 0 Here a new Configuration access code may be entered this can be a number in the range 1 to 32766 Note that entering a Configuration access code of 0 zero clears the Configuration access code Pressing Enter returns to step 1 above Page 21 MENU 15 22 Masterweigh 5 Operation MENU 16 REPORT PRINTING Optional This menu controls the automatic report printing function of the Masterweigh 5 This menu is only accessible if the real time clock module has been installed It is possible to configure the Masterweigh 5 to automatically produce a report via the RS232 serial port on either a time or mass total basis It is also possible to manually command a report at any time The format of the report is Masterweigh Report Date 29 06 00 Time 12 01 41 Mass total 2474450 tonnes Mass rate 5380 tonnes hour Menu step 1 displays the following 1 Menu entry 16 Automatic report printing Off Pressing Enter advances to Press Clear to print report NOW Press E to continue 1 Pressing Clear will cause report to be immediately printed via the RS232 serial port Pressing Enter advances to Report Mode Off Press Clear to change Enter to accept Pressing Clear toggles the report mode between off time based or total based Pressing Enter when report mode is Off returns to Step 1 above MEN
51. e phenomena usually occur on 240 110V AC power lines however they can also appear on the load cell input cables as well as the tachometer cables Masterweigh has been protected as far as possible however severe noise or spikes can get through Once any part of memory has been corrupted Masterweigh will detect it and automatically flag an error If the corruption has only changed data an error may not be detected and some erroneous results may occur The only way to clear the memory of this data is by re initialising Switching off and on will not clear the memory The act of re initialising causes all the calibration data to be lost and replaced by factory data The calibration data specific to your application can easily be re entered if you have kept a note of what was in the menus Menu 1 however does have specific data that is logged on the main PCB under Calibration zero and Precision ref LOG ALL CALIBRATION DATA AS YOU MAY NEED TO MANUALLY RE ENTER IT A LATER DATE TO RE INITIALISE MASTERWEIGH 5 PROCEED AS FOLLOWS 1 Switch off Masterweigh 2 Simultaneously press the Blank and Abort keys 3 With both the above keys pressed switch Masterweigh on 4 The display will now show the message Press C to Configure Any other key to continue 5 Now press the C key and Masterweigh will return to normal running mode 6 Masterweigh is now configured to factory defaults 7 Press Menu to enter
52. ed carriages which can be loaded with weights to simulate various belt loadings The disadvantages of calibration chains trains are as follows lt They generally expensive sometimes more expensive than the Belt Scale they are testing x They require additional personnel to set up x They have to be stored above the conveyor and therefore a storage structure has to be built lt They require maintenance Static Weight Test Static weight tests are the most common form of testing carried out on Belt Scales All Belt Scale manufacturers offer calibration weights as an option with the system the weight and quantity sized to approximate 75 80 of maximum belt loading The calibration weights are applied directly to the weighframe the belt is run and material loading is simulated The advantages of this method are as follows They generally the cheapest method They be applied by one person and for high belt loadings permanent weights that can be jacked off the weighframe can be installed material test be initially carried out they can be referenced to the material test results Repeatability tests are easy to carry out The disadvantages of static calibration weights are as follows lt They cannot exactly duplicate the running conditions of the conveyor lt They sit directly on the weighframe and therefore not duplicate the belt effects lt They tend to be lost
53. eigher the precision of the remote counter pulse or the remote counter pulse width 2 At this step the current feeder capacity is displayed new value may be keyed in then press Enter to continue Otherwise press Enter with no data entry to retain existing values and continue This value sets the 100 point for the 4 20mA mass rate output signal Note that the system can measure mass rates above this value assuming the instruments remain within their normal operating range and higher values will be shown on the screen and totalised However the 4 20mA mass rate output signal will show 20mA for all mass rates above this value Note that units can be changed to tons Ibs or kg if preferred within Menu Entry 11 3 This step displays and allows alteration to the mass total increment This increment is used for both the mass rate and the mass total displays Enter the new value required and press the Enter key No change is made if Enter is pressed without data entry Note that the increment set is the increment required to cause one pulse output from the electronic counter Also do not change the increment in normal operation as the change insetting will invalidate existing accumulated mass total 4 This step displays and allows alteration to remote counter pulse width this value is limited to between 20ms and 1000ms Note the value entry should be in multiple of 10ms 20 30 990 1000 No change is made i
54. eight 0 000 tonnes Press E to continue Mass rate 0 000 To Start span calibration Press E Mass Rate 0 000 Revs 0 0 To abort span calibration Press A Mass rate 1543 000 Revs 1 507 calculate new calibration Press Mass total 120 000 Revs 10 MENU 4 9 Masterweigh 5 Operation MENU 4 FIXED WEIGHT CALIBRATION Cont d 4 The target weight is the mass total that is expected over the number of belt revolutions as currently set Menu 2 This target weight may at this point be changed to suit the calibration weights being used Note that this value will generally be determined by running this procedure and recording the result immediately after performing empirical calibration Menu 5 A load zero calibration should generally be performed Menu 3 before running this procedure If a new value is entered then pressing the Enter key will save this as the new target weight If the Enter key is pressed without entering a target weight then no change to the stored value occurs 5 The current mass rate is shown the number of belt revolutions is zeroed Press the Enter key to start the test 6 Once started the test will run until the currently specified number of belt revolutions has been counted Refer to Menu 2 7 During this step the weight is totalised over the specified number of belt revolutions after which time totalisation is automatically stopped
55. ement to run the zero test Press enter again the display will change to the following Pulses per belt revolution Press E to save otherwise press A Press E to continue Mass rate a aaa By pressing the Enter E key the calculated data is stored in Masterweigh memory and will be used as a time base for zeroing and spanning calibrating The display will now return to Menu 2 entry display showing the new data If the A key was pressed no calculations would be done and the display would show previously stored data Zeroing Masterweigh Advance to Menu No 3 by pressing the key Where a aaa shows the current zero if the belt is running This data is raw that is not adjusted by the computer and will be changing frequently This information is mostly used by technicians Press the Enter key again and the display will change to the following Zero reset To start zero cal Press E Mass rate 0 000 Revs 0 0 GETTING STARTED 21 Scale GETTING STARTED Masterweigh is now ready to zero and will as soon as the Enter key is pressed again Masterweigh did not start executing its zeroing immediately because it gives time to make sure that the belt is empty most important After confirming that the belt is empty press the Enter key to start the zeroing The display will now change to the following To abort zero calibration Press A Mass r
56. ence between the current loadcell zero and the actual load reading is accumulated over the test duration which is the total number of belt revolutions specified in menu 2 The test can be aborted at any time by pressing the Abort key If the test is aborted the working copy of the load zero is reinitialised from the stored load zero calibration value This working copy normally includes contributions from both the load zero calibration as carried out in this menu entry and the auto zero tracking function It is thus possible by entering the menu to this level and then aborting to reinitialise the working copy of the load zero and remove any auto zero tracking contribution Masterweigh 5 Operation MENU 3 ZERO CALIBRATION Cont d 6 This display will come up automatically when the belt has completed the required number of revolutions The measuring phase of the test has finished and the resulting mass total is displayed This mass total should be approximately zero however if non zero then a new loadcell zero may be required Press the Enter key to display the millivolt offset resulting from this test 7 The new loadcell zero or offset is displayed in millivolts Press the Enter key to save this value as the new loadcell zero or press Abort to exit without saving Page 7 MENU 3 8 Masterweigh 5 Operation MENU 4 FIXED WEIGHT CALIBRATION This menu entry allows the automatic th T factor
57. ent of a Belt Scale may be for a variety of reasons Most applications require a Belt Scale to accurately weigh the total amount of material that has been conveyed from one location to another However some applications only require the Belt Scale to accurately measure the rate that the material is being conveyed at and the total figure is only of a secondary interest Other applications place great emphasis on both the total and rate results An example of a total application could be a shiploading operation where it is critical to know the actual total tonnes that have been loaded into each section of the ship The ship holds can be relatively easily topped up to the required weight however it is difficult to take excess tonnes back off the ship A Belt Scale can be installed on the ship loading conveyor to continually record the total tonnes that have been transferred onto the ship and thereby not have to wait for draft surveys to be carried out An example of a rate application could be a long drift conveyor transporting coal from underground to the surface It is important not to overload the conveyor as this may cause the conveyor to trip due to the excessive load This will then require the conveyor to be shovelled off so that the conveyor can restart A Belt Scale can be installed on the drift conveyor to measure the rate passing over it which can then be used to control the rate of feed onto the conveyor An e
58. ey and Melbourne We have a standard range of designs for equipment Where a customer has a special requirement we will where possible modify our design or design a new device to meet the application requirements Our feeders are currently in use with most of the major companies in Australia and our electronic systems are widely used in the U S A South America and Europe Web Tech is proud to include companies such as BHP Steel BHP Minerals BHP Temco BHP Australia Coal CSR Sugar amp Plaster Board Monier Queensland Cement amp Lime Tomago Aluminium Company Boyne Smelters Limited Blue Circle Southern Cement Swan Cement Boral Comalco Aluminium Incitec Mt Isa Mines Limited Port Waratah Coal Services Simplot Uncle Bens Kellogg Australia amp Malaysia SPC amongst our users Whe WEB TECH AUSTRALIA PTY LTD TABLE OF CONTENTS 1 BELT SCALE FUNCTIONS 2 THEORY OF OPERATION 3 BELT SCALE COMPONENTS 4 CONVEYOR DESIGN 5 WHICH MODEL BELT SCALE 6 ONGOING MAINTENANCE The information contained in this document remains the property of Web Tech Australia Pty Ltd and should not be reproduced or disclosed without their permission BELT SCALE SELECTION AND INSTALLATION GUIDE The following guide has been produced as an aid in the correct selection and installation of Conveyor Belt Scales This publication does not cover the operation of Nuclear Belt Scales 1 BELT SCALE FUNCTIONS The requirem
59. f Enter is press without data entry One pulse is output each time the mass total increases by one increment set in step 3 above 4 Masterweigh 5 Operation MENU 1 PARAMETER SET UP Cont d Enter a pulse width that will match with the remote counter response time but keep the following in consideration when selecting this value The pulse output can go no faster than the value you just selected but the accumulation of the mass total may and so the remote totaliser will fall behind the actual mass total E g if the pulse width is set to 100mS then at it s fastest rate the output will on for 100ms then off for 100ms This will give a maximum output of 5 complete pulses per second 100mS on and 100mS off 200mS per total pulse Therefore if the feeder is running faster than 5 increments per second 18000 increments per hour then the remote total will be wrong E g for an increment value of 0 01tonnes the limit will be 180tph To modify factory calibration data 5 At Menu Entry 1 press the C key to gain access to the factory calibration data The correct values for these calibration constants have been engraved onto the main board of the Master Weigh 5 stack the top board Check that the values in the computer are the same as the engraved values and modify the values in the computer as required 6 The display will warn the operator not to modify data and to press A to exit and c
60. here are no alignment faults within the alignment zone adjust idler assemblies upstream and downstream from the zone 0 effect acceptable belt tracking Finally Note and remember that any roll that may fail in service must be replaced by a modified roll grub screw fitted and aligned if performance specifications are to be maintained MECHANICAL INSTALLATION 21 Scale ELECTRICAL INSTALLATION ELECTRONIC ENCLOSURE It is advisable to mount the enclosure as close to the weighframe as possible The maximum cable length from weighframe junction box to the enclosure is approximately 150m However in our experience it is quite frustrating moving any distance between the weighframe and electronics during zeroing and calibration routines Fix the enclosure to a suitable post or wall It is advisable to select a position which is not subject to excessive vibration and is out of direct sunlight unless a sunshield if require contact Web Tech with details for pricing is fitted out of the way of running water during rain or hosing and easily accessible to an operator Note Close up the enclosure door to prevent ingress of water and dirt TACHOMETER INSTALLATION a General Refer to Dwg No s WT5013 Masterweigh uses the signal from the tachometer to calculate the belt speed The signal from the device is a train of 5 volt square wave pulses The pulses per revolution are selected by Web Tech to suit y
61. hours 1 Press Enter to continue Here a count of power on hours since the last unit re configuration is displayed This display is provided for information only it is not user adjustable Pressing Enter returns to step 1 above Masterweigh 5 Operation MENU 15 ACCESS CODE Masterweigh 5 provides for 2 levels of user configurable access code If no access codes are activated all Masterweigh 5 menus are accessible all the time An Operator and a Configuration access code may be entered AS soon as an access code is activated the user cannot leave the main mass rate total menu and gain entry to the menu system without entering a valid correct access code Entering the correct Configuration access code allows full access to all Masterweigh 5 menus and parameters Entering the correct Operator access code allows limited access to the Masterweigh 5 menu system Step 1 of this menu displays 1 Menu Entry 15 Press Enter to modify access codes Unless the special security key has been installed in link 3 of the CPU PCB the following menus cannot be accessed If the security key is installed then pressing Enter advances to 2 Operator Access Code Enter access code 0 Here a new Operator access code may be entered this can be a number in the range 1 to 32766 Note that entering and Operator access code of 0 zero clears the Operator access code If the security key is installed then pressing Enter a
62. igh can be used to display the load cell output With Masterweigh on and in the normal running mode press the Menu key and advance the display by pushing the key until Menu 8 appears Menu 8 display the load cell output in millivolts When the tare voltage has been set up return Masterweigh to the run mode by pressing the Menu key followed by the Enter key Finally seal up the junction box and make sure that the water can t enter via conduit connections etc Remember Water entering the junction box will adversely affect the performance of Masterweigh MECHANICAL TARE 21 Scale GETTING STARTED NOTE The following procedures will normally have been carried out at the factory This section includes a minimum of basic information to get you started Detailed procedures are to be found in Masterweigh Operation The set up sequence is Enter pulses revolution Zero Span Fine tuning Most Belt Scales require to be zeroed and spanned The time required to zero and span a system is determined by the belt speed and length It is recommended that a minimum time of about 5 minutes be used Note the longer the time and hence more revolutions the better Entering Pulses per Revolution To input this time into Masterweigh mark the conveyor belt with chalk or paint a particular point on the belt If there is already a distinguishing mark on the belt use that Select a static point
63. ill ensure that the striker bar stays in contact with the transportation block during the following steps If the calibration bars do not force the striker bar on to the load cell button loosen the tare screw 11 Using either piano wire or nylon fishing line 50kg breaking strain or greater run seven stringlines along the alignment zone These seven lines should be tied off on the two previously elevated idlers Two lines should be allocated to each of the wing rolls with three being allocated to the bed roll The lines must be very taut after tying off and there should be no measurable sagging No rolls wing or bed must contact any of the strings at this time If any rolls are contacting a stringline then the two idlers used to tie off the stringlines have not been elevated high enough or there is an idler profile mismatch between the new and old idlers Adding shims to the tie off idler will overcome one aspect of the problem but if the profile troughing angle is found to be causing stringline contact then those idlers must be changed to comply with the weigh idler profiles Note Make sure all weigh roll grub screws have been backed off so the roll shaft is in contact with the idler support brackets 21 Scale MECHANICAL INSTALLATION CONTD 12 Using packers and shims of various thickness elevate the non weigh idlers so that the rolls just contact the stringline If the rolls make too positive a conta
64. ing work should be carried out on a 12 monthly basis Lift belt and check all idler rolls for wear build up and bearing problems Carry out mechanical alignment check with stringlines Adjust balance on loadcells where applicable Apart from the general housekeeping of the installation the other important aspect that should be addressed is the record keeping for each installation Most modern Belt Scale electronics store all data in battery backed or non volatile memory however in the case of catastrophic failure this data will probably be lost or not accessible At these times it is essential that accurate records be available for reprogramming purposes Accurate records also allow review of the Belt Scale performance and possible problems that may require attention Web Tech has provided proper data record sheets that can be used in conjunction with the maintenance program BELT SCALE MAINTENANCE GUIDE Masterweigh 5 Operation Page 1 KEYBOARD LAYOUT AND KEY FUNCTIONS MASTERWEIGH 5 KEYBOARD LAYOUT TOTAL RESET ZERO CAL J ABORT E Masterweigh 5 operate protected security open mode depending how user has configured it See Security for set up details The following text assumes that the operator has gained access to the system SECURITY CODES If a user has entered security codes into the Masterweigh 5 entry
65. ist in the mechanical installation Conveyor Stringers The conveyor stringers should be rigid free from vibration and capable of supporting the load without deflection Weighframes and approach retreat idlers should not be installed where joins in the stringers exist If this is not possible stringers should be welded together using fish plates The stringers should be suitably supported in the area of the weighframe approach retreat idlers so that the total deflection within the weigh area does not exceed 0 25 mm BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Environmental Protection Where the conveyor is exposed to the elements errors may be induced by external influences such as wind Errors equivalent to 30 tonnes per hour have been measured on large conveyors subject to high wind velocities These errors can be minimised by installing guards which protect the weighframe and 5 metres of conveyor in each direction Where possible supply the Belt Scale manufacturer with a detailed arrangement drawing of the proposed installation with as many parameters as known WEIGHFRAME TO LOADING POINT DISTANCE The weighframe should be located far enough from the loading point to ensure that the material has achieved the same velocity as the conveyor belt Typically most materials will settle within 5 idler spacings of the loading point MAXIMUM CONVEYOR INCLINATION ANGLE Product Roll Back The conveyor incline angle
66. ks with previously set values As some conveyors experience surges of material then run empty as part of the plant s normal operating conditions Masterweigh can if instructed delay any autozeroing process for a predetermined time To enter the Autozero menu press the Enter key and the display will change to following Autozero level 20 000 tonnes hour Enter new level 0 000 At this point a new mass rate level can be entered Note this level should be sent at approximately 2 of the maximum flow rate On pressing the Enter key again the display will change to the following Autozero period 5 rev s Enter new period 21 Scale GETTING STARTED CONTD It is best to set this to the same number of belt revolutions as when the zero and span were set However fewer whole revolutions can be used if preferred Note by entering 0 into this entry the Autozero mode is switched off If the Enter key is pressed once again the display will change to the following Delay before auto zeroing 60 sec Enter new delay 0 Where XXXX delay in seconds Note When the autozero is running a lower case z appears on the display when load is detected it will be switched off Should appear where the z normally appears it means that the signal from the load cell has gone negative with respect to the normal load cell output The lower the
67. lectronic Integrator iv Calibration device i Weighframe and Weigh Idlers The function of the weighframe is to support the weigh idler s and conveyor belt and to convert the weight of the material within the weigh span to an electrical signal which can be processed by the electronics Weighframes are varied in design however the majority of the designs incorporate one or more transducers most typically strain gauge loadcells The weighframe is usually self contained low profile and designed to be installed within the limits of the conveyor structure The number of idlers used is dependant upon the accuracy required and the conveyor parameters Various weighframe designs exist each with their own perceived advantages Most Belt Scale manufacturers use either a pivoted design a fully floating design With a pivoted design one or more idlers are mounted ona frame which is pivoted at one end by some form of fulcrum point The fulcrum point is designed to be both maintenance free and as close to frictionless as possible Early pivot designs included knife edges and bearings or ball bearings however due to the perceived maintenance problems and the advent of transducers with very small amounts of movement these were replaced with components such as torque tubes flexures or rubber trunnions BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D The fully floating design comprises one or more idlers mounted on a frame
68. ligned weigher this figure should be approximately 1 to 2 of capacity MENU 6 14 Masterweigh 5 Operation MENU 7 AUTO ZERO TRACKING This entry specifies the mass rate level below which automatic zero tracking occurs and the number of belt revolutions required before a new zero level 15 established the Masterweigh Control of the Autozero Alarm relay is achieved from this menu The auto zero mode will not be entered or continue unless the mass rate remains below the specified level The value is normally set at approximately 1 5 of capacity A qualifying time delay period is also provided to ensure that the belt is completely free of material Should it be necessary to clear the present auto zero value then this can be done by entering Menu 3 load zero calibration then aborting after starting the test A z will be displayed at the right hand side bottom line of the main mass rate mass total display when the auto zero conditions are met and the Masterweigh is collecting data for a possible new zero level Note The auto zero tracking procedure is inhibited under the following conditions Masterweigh not in the mass rate mass total display mode Input tacho frequency less than 5Hz It may be required that the user wishes to know if the Autozero function is being forced to zero out belt zero errors which could be considered as abnormal This is achieved by setting a window around the signal
69. lity of the system to be severely degraded After the location for the scale s weighframe has been selected using the previous chapter as a guide carry out the installation using the following method Refer to Dwg No s WTE21 and WTE21 1 which are at the end of this manual 1 Electrically isolate the conveyor 2 Lift the conveyor belt so that clear access is gained to idlers numbered 1 to 12 Remove idlers 4 5 6 7 8 and 9 Examine idlers 1 2 3 10 11 12 and check Replace if not sound Square up idlers 1 and 12 Elevate to approximately 1 2mm It is important that these two idlers be square with respect to the stringers and are securely bolted down prior to proceeding The measurement between idlers 1 and 11 divided by 11 will from there on be referred to as the pitch The pitch must be an achievable measurement over the 12 idlers under discussion The zinc plated brackets to which the idler will eventually be welded are manufactured with slotted mounting holes Check and set the measurement between the centre of the torque tube pivot Point and the centre of the first idler on the weighframe at 219mm If the desired pitch cannot be obtained move the two idlers 1 and 12 to assist 3 Locate the weighframe assembly Carefully remove it from its wooden crate Do not lift it out by the load arms the load arms will be marked with warning signs to this effect Place the frame into a position where the weighi
70. locity as the belt Typically for most products this is approximately 5 idler spacings or 6 metres Conveyor Inclination Ideally the conveyor would be horizontal to provide for more consistent belt tensions however this is not generally practical The conveyor inclination angle should not be so great as to allow the product to roll back This will cause a positive error from the Belt Scale Concave and Convex Curves Concave curves should be avoided where possible The weighframe should be located as far away as possible from the tangent point of the curve and no closer than 20 metres Convex curves are less of a problem however the weighframe should be located no closer than 6 metres from the tangent point of the curve Conveyor Take up The conveyor should preferably be fitted with gravity take up on the return belt Gravity take ups located on the tail pulley are acceptable however less desirable Screw take ups on short conveyors less than 15 metres may be acceptable however not preferred Belt Loading Belt loading should be uniform and consistent Belts should be sized so that they are volumetrically 75 80 full BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Belt Type The selected belt type should use the minimum number of plies possible Additional plies add to the stiffness of the belt and therefore reduce the achievable accuracy Steel cored belts are the least desirable due to the stiffness of these belts Co
71. mass total accumulated over the period will be zero The display shows the currently stored value in millivolts as read at the load cell input including any contribution made by the autozero function Note that the zero value is automatically adjusted if the excitation voltage changes 1 Menu entry 3 Zero cal 2 563mV 2 563 7 2 Manual entry of Zero Error or press Enter to continue 3 Press E to continue Mass rate 0 000 4 Zero reset To Start zero cal Press Mass rate 0 000 Revs _ 0 0 0 000mV 5 To Abort zero calibration Press A Mass rate 0 000 Revs 0 0 6 To calculate new calibration Press E Mass total 1 150 Revs 10 7 Zero error 2 756 millivolts Press E to save otherwise press A MENU 3 1 At Menu Entry 3 press Enter to proceed 2 Optional Using digital voltmeter measure the belt zero error value in millivolts at the loadcell or read the mV level displayed in menu 8 Manually key in the value to the Masterweigh and press the Enter key to accept Otherwise press Enter with no data entered to continue with no change Note that entering this value does not negate the need to perform a zero calibration 3 The live zero error is now displayed as a mass rate Press Enter for the loadcell calibration procedure 4 The mass total will now display zero Check that the belt is empty then press the Enter key to begin the zero calibration test 5 The differ
72. menu entry 1 then press C to enter the calibration data section The display will warn you not to continue Press E to continue 8 The display will request a new Calibration Zero to be entered Enter the value that is engraved onto the right hand side of the main pcb under the label Cal Zero then press E 9 The display will request a new Precision Reference Enter the value that is engraved onto the right hand side of the main pcb under the label Prec Ref then press E 10 Press M then E to return to normal running mode Remember If MW5 is reconfigured all calibration data is lost Keep Notes RECONFIGURING MASTERWEIGH 24 Masterweigh 5 Operation FACILITIES AVAILABLE Introduction The Masterweigh is a precision microprocessor based instrument for accurate integration of mass totals in belt scale applications The core highly successful Masterweigh 1 design has been in operation for many years and has been proven in the field and tested by the National Standards Authority Australia The tests on the core proved that the instrument is accurate to 0 1 over its operating range The operating environment is based on a series of discrete Menus Each menu allows the user to set up a working environment or calibrate the system For a detailed description of each menu refer to the following pages of the manual Note that detailed information relating to the keyboard operating command pro
73. mode Press to change Enter to accept The Masterweigh 5 real time clock can be configured to display the current time in either 12 or 24 hour mode the selection is made in this menu Pressing Enter advances to 4 Time 09 13 56am Enter new time HHMM Here the current time is displayed and may be modified A 4 digit time string of the form needs to be entered Where HH is the desired hours ie 12 03 etc and MM is the desired minutes 45 07 etc E g to enter 9 30 press 0 9 3 0 E Pressing Enter advances to MENU 14 5 Time is currently Press to change Enter to accept Here the current 12 hour time format postfix is displayed and may be modified The user can select either am Pressing Enter advances to 6 Date 29 6 94 Enter new date DDMMYY Here the current date is displayed and may be modified A 6 digit time string of the form DDMMYY needs to be entered Where DD is the desired days ie 27 04 etc MM is the desired months ie 11 05 etc and YY is the desired years ie 94 01 etc E g to enter 12 Feb 2000 press 1 2 0 2 0 0 E Pressing Enter advances to 7 Day of the week Wednesday Press to change Enter to accept Here the current day of the week is displayed and may be changed by the user Pressing the key toggles through the days of the week Pressing Enter advances to 8 Power on
74. n 12 and 13 if link LK3 is correctly installed and should be checked when configuring the Masterweigh Allow 30 seconds for update of display after adjusting the excitation Incorrect configuration of excitation sensing will cause erratic mass rate readings The millivolt input accepts either a differential millivolt signal or a half bridge input and will operate accurately over a common mode range of minus 8 to plus 8 volts The input is overload protected to plus or minus 35 volts on either terminal with the Masterweigh energised and plus or minus 20 volts on either terminal when not energised Transient overload capacity is much higher than this continuous rating and depends the duration of the overload Masterweigh 5 Operation Page 25 FACILITIES AVAILABLE Cont d Load cell Input and Excitation Contd The analog digital conversion is performed using voltage to frequency conversion techniques thereby providing excellent rejection of signal noise over a_ wide frequency range With the exception of short periods allocated to self calibration Masterweigh is continuously monitoring the load cell input rather than periodically sampling as is the case for systems which use dual slope integrating converters This results in a more accurate measurement of the rapidly fluctuating input signal from the load cell Careful design of the input circuitry ensures excellent rejection of common mode signals both A
75. n board half bridge circuit This half bridge is energised from the excitation as supplied to the external device The zero point is adjustable via RV1 Refer to Section Potentiometer Adjustments RV1 LK4 LK5 Current loop supply These links select the power supply for the analog output current loop The supply can be an internally generated isolated 28VDC supply or an external supply of 20 to 50VDC Set the links to select the appropriate power source as follows Internally generated LK4 LK5 1 2 1 2 Externally generated USER CONFIGURATION LK4 LK5 2 3 2 3 LK6 LK7 LK9 Control Pulse Output Type These links select the power source for the totaliser counter pulse output Set the links to suit the external counter device Internally generated 5VDC not isolated 1 6 LK8 9 1 2 1 2 1 2 1 2 Internally generated 28 VDC Isolated LK6 8 9 1 2 1 2 2 5 2 3 Relay provided voltage free contacts 1 6 LK9 2 3 23 2 3 2 3 LK1 When installed to the bottom Masterweigh s digital communication is based on the RS232 protocol When installed to the top the digital communication is based on the RS485 protocol RS485 communications are only available if the main board has the relevant optional components installed LK2 Not user configurable Link 1 4 amp 3 6 or leave un linked Masterweigh 5 Operation Page 29 POTENTI
76. ng idler assembly can be easily welded onto the support bracket sometimes loading the frame into the conveyor stringers is the most convenient 4 Drawing WTE21 shows the load cell positioned within the body of the weighframe carried on a stainless steel plate This plate positions the load cell so that it contacts the weighframe s striker bar The weighframe is supplied with a transportation support block in place of the load cell The block is of the same dimensions as the load cell and must be left in place whilst the installation procedure is taking place Load Cells can be easily damaged by shock loading overload or welding in the vicinity of the cell Web Tech reserve the right to cancel any warranty on the load cell if it is damaged for any of the above reasons 5 The zinc plated brackets are affixed to the torque arms by two bolts These bolts fit through two elongated holes in the brackets Make sure that the brackets either side of the frame are either fully forward or fully back prior to proceeding to the next step MECHANICAL INSTALLATION 21 Scale MECHANICAL INSTALLATION CONTD 6 Lift the idler assembly onto the zinc support brackets and centralise the assembly so that the zinc angle iron support straddles the weighframe evenly The rolls can be removed if the assembly is heavy and unmanageable 7 Weld the angle iron of the idler brackets to the zinc brackets It is advisable to
77. ntered a belt speed this value will be the calculated belt length If it seems correct Press enter to save the value or abort to ignore the calculation Note that if you entered a belt length in step 3 and not a belt speed in step 4 this value will be meaningless Press E to continue Masterweigh 5 Operation Page 19 MENU 13 CLEARING MASS TOTAL Menu entry 13 Press C to clear Mass Total 1 When the mass total on the mass rate mass total display MRMT is to be zeroed press C at Menu Entry 13 All totalised figures are then cancelled by the integrator Press Menu then Enter to return to the display MENU 13 20 Masterweigh 5 Operation MENU 14 REAL TIME CLOCK This menu controls the operation of the Masterweigh 5 real time clock The real time clock is a separate module with its own battery power source that will continue to keep accurate time even in the case of power loss to the Masterweigh 5 unit This menu is only accessible if the real time clock module has been installed Step 1 displays the following current time date and day of week information 1 Menu entry 14 Wed Time 09 12 43am Date 9 6 94 Pressing Enter advances to 2 Elapsed Time Press clear to reset 0 days 00 19 58 hours Here a free running elapsed time count is displayed Pressing Clear will reset the elapsed time counter Pressing Enter advances to 3 Clock is currently in 12 hour
78. nveyor belts should be uniform in weight with a minimum of splices Metal clip fasteners should not be used Belt Tracking Belt tracking should be central to the idlers regardless of belt loading Training idlers should not be used any closer than 5 idler spacings from the weighframe Conveyor Idlers It is more desirable to use idlers with shallow troughing angles Idlers with 20 angle are better than 30 angle and 30 is better than 35 Idlers with 45 troughing angle be used however errors due to belt tension changes are more significant The steepness of the troughing angle determines the planar moment of inertia of the belt which determines how susceptible the Belt Scale is to belt tension variations and misalignment Idlers on the weighframe two approach and two retreat idlers should be In Line Weigh Quality Rolls should be machined concentric to provide 0 13 mm Total Indicated Runout Rolls to be balanced within 0 011 Nm Rolls to be fitted with some form of height adjustment On some low accuracy applications some of the above requirements may not be required Idler Alignment The mechanical alignment of the weigh approach and retreat idlers is critical The height misalignment in this area should be no greater than 0 4 mm Mechanical misalignment of these idlers will cause the accuracy of the system to vary depending on belt tension variations It is advisable to have the Belt Scale supplier ass
79. o Source Ext Con Press Clear to change Enter to accept 1 Press E to enter the menu to select the source of the tachometer signal MENUS 8 amp 9 2 Press C to change or toggle between the available pulse sources which are Hardware input signal to the system as generated by the speed sensor Magnetic pick up or optical tachometer Simulated an internally generated 100 2 signal that is always on e Ext Con an internally generated signal that is only on when an external contact is closed between terminals and on terminal strip J3 usually auxillary motor contacts 3 Press E to accept and return to the Menu Entry 9 Masterweigh 5 Operation Page 17 MENU 10 FILTER CONSTANTS Filtering can be applied to the following functions Displayed mass rate 4 20mA mass rate output Tacho input The level of filtering is specified by a constant that may be in the range 1 second to 120 seconds Time constants greater than 120 seconds have the same effect as a 120 second constant A time constant of 1 second is equivalent to no filtering Time constants greater than 1 second introduce a delay in the rate of change of the filtered function 1 Menu Entry 10 To modify Filter factors press Enter 2 Display Time constant is 2 secs Enter new Time constant 0 3 Rate O P Time constantis 4secs Enter new Time constant 4 Tacho Time constant i
80. ole positive range of the load cell to be used To mechanically tare the weighframe proceed as follows 1 Make sure that the connections in the junction box have been made and that all connections to Masterweigh have been made 2 Switch on Masterweigh and observe that the mass rate and total display appears 3 Using a digital multimeter of 3 1 2 digits or better and with the millivolt scale selected place the probes across load cell positive green wire and the loadcell negative white wire If the Web Tech junction box is being used then red probe is placed on and the black probe on TP2 Remove links LK1 amp LK2 Now the load cell output has been isolated and the mechanical tare procedure can take place Observe the reading which should be 2 5mV If not then adjust the tare screw so that approximately 2 5mV is achieved 2 5 0 5mV By screwing in the tare screw the reading will decrease until it goes to approximately 0 06mV Screwing the screw out will cause the millivolt reading to increase The maximum value is dependent on the capacity of the load cell and the weight of the idlers Once the digital voltmeter reads approximately 2 5mV lock the screw by tightening up the lock nut making sure that the action of tightening the lock nut does not cause the tare screw to move and hence change the tare output from the load cell If a digital multimeter is not available then Masterwe
81. ontinue Press the E key at this point for access to the Zero Reference 7 Enter new data and or press the E key to proceed Now access to the precision reference has been gained Enter new data and or press the key gt again 8 Either exit at this step by pressing the A key or press E to access the menu which exercises the 4 20mA output 9 Press C to step through the Rate O P s to the desired value namely 20 0 10 04 5 02 7 53 6 27 5 645 5 335 5 178 5 099 1 790mA Press E to reset unit A current meter needs to be connected across pins 6 amp 7 of J3 and in series with the load if connected MENU 1 Masterweigh 5 Operation Page 5 MENU 2 PULSES PER BELT REVOLUTION This calibration is carried out with the belt moving The number of complete belt revolutions over a time period are counted by the operator and the Masterweigh counts the pulses returned from the speed sensor device The revolutions are then entered using the keypad and _ pulses rev calculated by Masterweigh and then saved To enable the revolutions to be counted a point on the belt should be marked with paint and a suitable point on the framework chosen close to the belt The count is then started as the belt mark passes this point and stopped as the mark again passes this point after the greater of 5 minutes or 5 belt revolutions 1 Menu entry 2 Pulse per rev 2 Manual entry of Pulses Rev or press Enter
82. our conveyor s performance from the following range 100 500 1000 The tachometer selected will normally supply pulses at a rate of between 400 and 600 per second Masterweigh has been designed so that if the pulse rate exceeds approximately 900 per second they are automatically cut off therefore Masterweigh will read zero mass rate If ever necessary it is important to replace the tachometer with one with the same number of pulses per revolution b Tachometer Positioning The preferred position for the tachometer is the tail pulley The tail pulley has a large angle of wrap and because it is not driving it is unlikely to slip Its relatively large diameter is not normally affected by material build up also is less likely to be speed sensitive to the effects of belt thickness variations Whilst the tail pulley is normally subjected to harsh environmental conditions the Web Tech tachometer has been manufactured to cope If you are unable to place the tachometer in the tail pulley consult Web Tech As there are many different conveyor designs and hence tail pulley fixings we do not supply a fixing bracket for the tachometer See Dwg WT5013 for a suggested method Whilst the spring coupling will accommodate small misalignments without any problems large misalignments will cause premature failure of the coupling When connecting the spring coupling it is advisable to smear anti freeze grease onto the tail pulley s snub
83. ow this level the mass rate display will show zero no increment of the mass total will occur no pulse outputs to the pulse counter and the mass rate analog output will be set to 4 1 Menu entry 6 Null level 20 000 tonnes hour 2 Enter a new null level 25 Mass rate 22 657 tonnes hour 3 Enter belt scale total 0 000 4 New span 205 6 Previous 211 7 Press E to save otherwise press A 1 At Menu Entry 6 press Enter to proceed 2 Enter the exact mass total as measured by the weighbridge or other accurate method Press Enter when the data is correct 3 Enter the mass total as measured by this Masterweigh unit Press Enter 4 Press Enter to store the new span value as the loadcell span calibration factor Press Abort if no update is required 5 At Menu Entry 6 press Enter to proceed 6 Key in the new null level of zero Press Enter when the data is correct Note on selecting the null level This entry is used to mask variations in mass rate caused by variations in the belt weight caused by the belt splice etc To select the null level observe the mass rate shown over several belt revolutions with the belt running completely empty ie no product or calibration weights Take note of the highest equivalent mass rate reached then enter a value slightly higher than this level Eg if the mass rate was swinging from 20 to 0 to 20 select 22 as the null level On a correctly installed and a
84. rminal P Pulse Negative Belt Speed Sensor Terminal Strip J3 The belt speed sensor tacho is connected to terminals DG T and T Terminal DG Ground Terminal T Tacho Output Terminal T Tacho 5 VDC Supply Rate Output 4 20mA Terminal Strip J3 Masterweigh 5 provides a 4 20 mA analog output which can be used for remote rate meter PLC DCS The output is optically isolated Terminal A Negative Terminal A Positive Load Cell s Terminal Strip J3 Load cell s connections to Masterweigh are made via terminals AG L L E and Terminal AG Load Cell Screen Terminal L Load Cell Output Positive Terminal L Load Cell Output Negative Terminal E Load Cell Supply Positive Terminal E Load Cell Supply Negative ELECTRICAL INSTALLATION 21 Scale ELECTRICAL INSTALLATION CONTD RS232 Serial Output Terminal Strip J5 Masterweigh 5 is provided with an RS232 serial output Terminal GND Ground Terminal TxD Transmit Terminal RxD Receive RS 485 Serial Output Terminal Strip J6 Optional Feature Masterweigh 5 is provided with an RS 485 serial output Terminal Tx Transmit Terminal Tx Transmit Terminal Com Ground Terminal Rx Receive Terminal Rx Receive ELECTRICAL INSTALLATION WTE21 Scale MECHANICAL TARE One of the advantages of using a torque tube is that the dead load can be supported thus allowing the wh
85. rom the conduit Load Cell Electrical Connections Refer to Dwgs WIMW5 01 1 WTMW5 01 7 Locate the junction box on the conveyor stringers preferably on the easy access side Bring all conduits in from the bottom of the junction box so that water ingression is limited Connect the load cell to the terminal block shown Connect load cell Masterweigh interconnect cable to J5 as per drawing ELECTRICAL INSTALLATION Note Water dirt coal dust etc will degrade the system performance Make sure that the Junction box is always properly sealed Commercially available sealants that use acetic acids as an accelerator can cause acidic fumes which condense of the PCB and cause electrical leakage Use Neutral Cure Based Sealants Power Connections Masterweigh can be supplied with 240 or 110V 50 or 60Hz or optionally 24 48VDC Check that the slide switch on the power PCB is set to the appropriate supply voltage if supplied with AC supply Masterweigh is protected against most industrial electrical noise If problems are encountered an external mains power filter should be used Power Connections Terminal Strip J1 Refer to Dwg WIMWS 01 1 WTMWS5 01 7 Masterweigh 5 can be supplied 240 or 110VAC 50 or 60Hz Check that the slide switch below the transformer is set to the required supply voltage Terminal Active Terminal N L2 Neutral Terminal G Earth Ground Masterweigh is
86. run the welds along the front and rear of the angle iron on the brackets It is also advisable to protect the welds with cold galvanised paint 8 Fit the weighframe into conveyor making sure that it is not lifted by the torque arms Place the weighframe halfway between the first of the original downstream and upstream idlers Note that the weighframe is usually orientated so that the two vertical arms which retain the calibration bars are in the upstream position However if the conveyor is inclined the weighframe can be fitted with the calibration bar stops downstream Now load the two upstream and downstream weigh idlers followed by the remaining two upstream and downstream idler assemblies 9 Carefully space out the idlers and weighframe dividing the entire alignment area into eleven Note The idlers that have been mounted on the weighframe can also be adjusted by means of the slotted zinc angle brackets The measurement from the torque tube to the first idler must be 305mm When it has been confirmed that all idlers are of equal pitch diagonally square and square with respect to the stringers and belt mark out the fixing hole positions and drill them MECHANICAL INSTALLATION Remove all swarf from the drilled holes before proceeding 10 Loosely bolt down all idlers and the weighframe making sure that the load cell contacts the transportation block Two calibration bars loaded onto the load arms w
87. s 1 secs Enter new time constant 1 Press Enter to modify the display filter time constant 2 The display mass rate filter time constant is shown When a time constant of greater than 1 is selected the main mass rate display is damped A new value for the display filter constant may be entered 3 The 4 20mA mass rate output filter time constant is now displayed A new value for the mass rate output filter constant may be entered 4 The tachometer input filter is displayed here and a new constant applied if necessary Note At each step pressing the Enter key will save the new value If a new value has not been entered then the current value is unchanged MENU 10 Page 18 Masterweigh 5 Operation MENU 11 MODIFICATION OF DISPLAYED UNITS The displayed units for mass may be selected from tonnes lbs tons and kgs displayed units for mass rate will be the same as those selected for mass ie tonnes hour Ibs hour tons hour kgs hour 1 Menu entry 11 To modify display units Press E 2 Ibs 4 tonnes 1 Pressing the Enter key will advance to select mass units 2 this stage the mass units which be displayed are shown To select the mass unit required press the number key associated with it then press the Enter key The units number selected will be shown in the lower right hand corner of the display Numbers greater than 4 will not change the currently displayed
88. stal display used the Masterweigh provides LED backlighting for improved readability under adverse light conditions If the unmarked key has not been activated then the display will switch off if any key has not been used within 5 minutes System Output Status A voltage free contact has been provided for remote monitoring of Masterweigh autozero function If the autozero function returns a value that is outside the high and low limits that were set in Menu 7 the relay will energise It will remain energised until an operator initiated zero is performed in Menu 3 FACILITIES AVAILABLE 28 Masterweigh 5 Operation USER CONFIGURATION Power Supply PCB Lower Board LK1 Grounding When the shunt is in position Masterweigh is referenced to ground When open Masterweigh is floating LK2 Excitation Selection This link allows the user to select either a unipolar or bipolar excitation voltage Refer also to Section Input and Excitation Unipolar OV is used for excitation voltages in the range 4 to 13 volts Selecting bipolar VE allows a plus minus excitation with a total voltage within the range 16 to 25 volts LK3 On Board Half Bridge This link allows use of input devices that have a half bridge configuration When linked for half bridge input micro the negative side of the load cell input is disconnected from the terminal block J6 and instead connected to an o
89. start span calibration Press E Mass rate 0 0000 Revs 0 0 This display indicates that Masterweigh is ready to start and requires that the Enter key be pressed again On pressing the Enter key the display will change to the following To abort span calibration press A Mass rate m mmm Revs Where m mmm the current mass rate prior to calibration r r belt revs that have elapsed When Masterweigh has timed out the display will automatically change to the following To calculate new calibration Press E Mass total tt ttt Revs r r Where tt ttt Mass total r r Number of revs On pressing the Enter key Masterweigh uses the target weight and the found mass total to calculate it s new span factor NOTE The above calibration data will not be stored in the Masterweigh working memory until the following key sequence has been carried out 1 Press Menu 2 Press E Enter key If A Abort 15 pressed instead of E Enter then the new calibration information is lost and Masterweigh uses previous data The same loss occurs if power is lost during calibration GETTING STARTED 21 Scale GETTING STARTED CONTD Fine Tuning Now that the system is running it can be fine tuned a Null Level Most conveyor belts have sections which are much heavier or lighter than the average weight of the belt To stop Masterweigh adding small amoun
90. surface such a splice passes under it This will cause a variation in frequency output and therefore the measured belt speed wheel is usually mounted on the return belt adjacent to the weighframe This can be along distance away from the weighframe by belt travel and therefore the belt speed measured may not be the same belt speed at the weighframe BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Belt Travel Sensor A belt travel sensor usually consists of one or more flags welded to a pulley usually the tail pulley and a proximity probe As the flags pass by the proximity probe they are counted and this relates to the amount of conveyor belt that has passed around the pulley The advantage of this type of system is that it is relatively simple and robust however the disadvantage is that it is low frequency in output and therefore the resolution can be coarse iii Electronic Integrator The electronic integrator is designed to carry out the following basic functions Provide supply voltages to weighframe transducers and speed travel sensors Measure and integrate the instantaneous weight weighframe and instantaneous belt speed travel which calculates the Mass Rate and Mass Total passing over the conveyor Provide analogue and pulse outputs for remote equipment Provide facilities for calibration The electronic integrator may also provide the following options Provide
91. ten used where a chain is impractical to use Bars of a known weight are loaded directly onto the weighframe and hence simulated a load This method does not take into consideration belt tension or weight transfer through the belt It does however exercise the weighframes mechanics 4 R Cal is an electronic method of checking the calibration A simulated loadcell signal is created by running the belt empty and electronically unbalancing the loadcell by switching in a reference signal across one arm of the loadcell bridge This method provides a reasonable method of quickly checking a weightometer but is no substitution for the aforementioned calibration methods The software required to implement this function is supplied in all Masterweigh 5 units but the hardware required for the use is an optional extra and therefore only supplied to order Assuming that your system is rigged for R Cal proceed as follows 10 Masterweigh 5 Operation MENU 4 FIXED WEIGHT CALIBRATION Cont d Initially calibration Menu 4 should be accessed and the enter key pushed until the sub menu Span Cal Mode is reached Menu 4 Span Cal Mode R Cal Press Clear to change Enter to accept Toggle the clear key until R Cal has been selected Now proceed as for normal calibration which is performed as described under Menu Entry No 4 When Masterweigh 5 completes the test note the number but do not accept it by pressing enter
92. than 0 5 It operates as loop powered configuration therefore derives its operating power from the 4mA residual loop current A minimum of 20 volts is required to operate with zero ohms load rising by 1 volt for every 50 ohms of load ie 30 volt supply required for 500 ohm load The output can operate with supply voltage of up to 50 volts and provides excellent rejection of power supply ripple and noise The loop power supply thus need not be heavily filtered or regulated An unregulated DC supply is provided on the Masterweigh board which can be used for energisation of the analog loop This supply provides a nominal 28V DC and is isolated from the Masterweigh ground Links are provided on the board to enable this supply to energise the analog output To use an external loop supply configure links LK4 and LK5 the board appropriately and connect the external supply in series with the analog loop Span calibration of the output is readily performed by accessing the analog calibration in the Menu 1 set up There is no provision for zero adjustment on the analog output Earthing This is achieved by installing the shunt on LK1 link located on the lower pcb above the capacitors Installing this link will connect the Masterweigh s digital and analog grounds to power earth FACILITIES AVAILABLE Masterweigh 5 Operation Page 27 FACILITIES AVAILABLE Cont d Display Backlighting The liquid cry
93. that can be easily used as a reference point to start and stop counting belt revolutions Set the Belt Scale running Masterweigh should now be switched on Press Menu key and then to advance to Menu Entry No 2 If the instrument is new it may show the following Menu Entry 2 Pulse per rev 1000 This is a factory entry and will change to the application values when entered To gain access to change these values to your GETTING STARTED application press the Enter key The display will now change to the following Manual entry of Pulses Rev or Press Enter to Continue This entry is used when the number of pulses per revolution is known and is not applicable to a new installation Press the Enter key to advance and the display will change to the following Manual entry of No of Revs or Press Enter to continue Once again this entry is not normally used in a new installation Press the Enter key to advance and the display will change to the following To start belt pulse count Press E Pulses counted 0 Time 0 You should now wait until the mark on the belt coincides with the selected reference point and as they coincide press the Enter key The display will now change to the following To stop belt pulse count Press E Pulses counted yyy Time 1 Time elapsed since pressing key 21 Scale
94. the actual weight on the conveyor belt and the second variable is the actual belt speed or belt travel The weight of material on the conveyor belt is obtained by measuring the load on one or more idlers This load can then be expressed in terms of kg metre W of belt The belt speed or belt travel is measured by using a device which gives an output proportional to the belt speed S or belt travel T The flow rate of material passing over the Belt Scale can be expressed as Rate WxS WEIGHT BELT SPEED FLOW RATE Weighframe Belt Speed Sensor The total weight of material that has passed over the Belt Scale can be expressed as Total W x T WEIGHT BELT TRAVEL Weighframe Belt Travel TOTAL WEIGHT Sensor Belt Scale manufacturers use either the belt speed or belt travel methods depending on their design philosophy Those that use the belt travel method generally use a low frequency device which delivers a number of pulses per unit of belt length The integration primarily calculates the total weight from which the flow rate is then derived The second method is to use a high frequency device up to 1 KHz the output of which is proportional to the belt speed The integration primarily calculates the rate passing over the Belt Scale from which the total is then derived Due to the availability of high speed processors most modern Belt Scales use the rate method as the basis for their electronic design
95. timed function of the backlighting That is under normal operating conditions the back lighting will automatically switch off 5 minutes after the last keypad operation NUMERIC KEYS These keys are used to enter calibration data KEYBOARD LAYOUT AND KEY FUNCTIONS Masterweigh 5 Operation Page 3 MENU 1 PARAMETER SET UP Menu 1 is used firstly to enter the maximum capacity of the weigher and the precision of the remote counter pulse 1 Menu Entry 1 Parameter Set Up 2 Current capacity 1000 000 tonnes hour Enter new capacity 0 000 3 Mass total increment 1 000 tonnes Enter new inc 10 0 001 0 000 4 Remote totaliser pulse width 100ms Enter new value 20 1000 0 Menu 1 can also be used to access and modify the precision zero reference and reference voltage by pressing the C key It is advisable however not to adjust this data unless the unit has been reconfigured 5 Menu Entry 1 Parameter setup 6 WARNING Calibration data Do not modify Press A to continue 7 Calibration zero x xxx milli volts Enter new zero ref 0 000 8 Precision ref x xxx millivolts Enter new precision ref 0 000 9 Press for Rate span calibration else press A MENU 1 10 Rate O P x xxmA C for next E to reset unit 1 At Menu Entry 1 press Enter to examine or modify the maximum capacity of the w
96. to continue 3 Manual entry of N of Revs or press enter to continue 4 To start belt pulse count Press E Pulse counted Time 1000 Revs 5 5 To stop belt pulse count Press E Pulses counted Time 6 Enter number of belt revolutions Pulses counted Time 7 Pulses per belt revolution Press E to save otherwise press A 1 At Menu Entry 2 press Enter to proceed with calibration 2 Ifthe pulses per rev are known then manually key in the number of pulses and press E Otherwise simply press E to continue 3 Manually key in the number of revs for the above number of pulses and press E Otherwise press E to continue 4 At the moment the belt mark passes the fixed point chosen press E to start the Masterweigh counting pulses and start counting revolutions Note that the display panel will show the counting 5 After at least 5 minutes press E again to stop the count as the mark passes the fixed point 6 Key in the number of revolutions counted and press E to confirm 7 Press E to save the number of pulses rev just calibrated otherwise press A to abort and return to the original values if any MENU 2 6 Masterweigh 5 Operation MENU 3 ZERO CALIBRATION This menu entry enables the operating zero to be calibrated A specified number of belt revolutions are run as determined by Menu 2 with no material or calibration weights on the belt If the zero is correct then the
97. top level menu screen is then displayed Similar to Abort except that current screen data only is cancelled and the existing entries restored The display remains at the current screen ENTER In menu mode key accepts the default setting or confirms any data entered and moves to the next level in the operating sequence In MRMT display mode if the Enter key is pressed the current CPU central processor unit status is displayed and also the number of times the CPU has been restarted KEYBOARD LAYOUT AND KEY FUNCTIONS 2 Masterweigh 5 Operation KEYBOARD LAYOUT AND KEY FUNCTIONS Cont d If the display is flashing the CPU fault status may be viewed by pressing the enter key in the MRMT display mode SPEED KEYS TOTAL RESET When this key is pressed MW5 clears the accumulated mass total Pressing this key takes the operator directly to the belt zero function without having to scroll through the menu structure CAL When this key is pressed the operating display jumps to the fixed weight calibration function ready to span the system 2 The blank key has been deliberately left this condition as it is a key that will be assigned to user s requiring special functions ordered as option However if no options are required this key provides the user with a method of switching on and off the displays back lighting The action of this key overrides the normal
98. ts of weight to its total during those periods when the belt is running empty Masterweigh has a menu entry which is called Null The joint in the belt is a major cause of small amounts of weight being added to the totaliser and the effects of the joint can be seen by entering Menu 6 The display will change to the following Enter a new null level 0 000 Mass rate 0 165 tonnes hour By running the belt empty in this menu the raw empty belt mass rate can be observed As the joint or any other belt abnormality passes the weighing element observe the highest mass rate value achieved over one belt revolution and enter a null value just higher than the mass rate noted b Autozero Tracking Material sometimes builds up on the conveyor belt and the weigh area even though belt scrapers are used and Masterweigh s weigh area is narrow Masterweigh can automatically compensate for these build ups if Menu 7 is activated Advance Masterweigh to Menu 7 At the point of entry Masterweigh displays the following if no entry has been previously entered GETTING STARTED Menu entry 7 Zero track if lt 20 0 for 4 revs This display tells us that Masterweigh will automatically force itself to read zero when the recorded mass rate is less than 20 tonnes per hour and stays below that value for the duration of five belt revolutions Should material start to flow Masterweigh immediately cancels the Autozeroing and wor
99. ty idlers are also supplied for the two approach and two retreat idlers to the weighframe Idler roll height is adjustable to allow for accurate alignment of the idlers within the weigh area Weigh Quality idlers are available from most idler manufacturers The following design aspects should be confirmed when considering a proposed weighframe Self contained and preassembled for easy installation Rigidity with great emphasis placed on eliminating deflection Provide minimal surface area for material build up Provide equal loading all transducers BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D Provide maintenance free and frictionless pivot points Be provided with mechanical tare facility for lightly loaded conveyors Reduce the effects of material off centre loading ii Belt Speed Travel Sensor As previously discussed a sensor is supplied to provide a signal to the electronic integrator as to the actual belt speed or belt travel Belt Speed Sensor Belt speed sensors be supplied in several arrangements The most common method is for a rotary type sensor to mounted in an enclosure to be connected to a shaft pulley usually the tail pulley As the pulley rotates the speed sensor shaft is also rotated which in turn produces a pulse output The frequency of the pulse output is proportional to the rotational speed of the pulley Typical frequencies fall within the range of 100
100. ular calibrations These visits can also be used to provide basic training for the site personnel in the event of an emergency breakdown situation These site visits are normally scheduled at three monthly intervals The following work should be carried out on a regular basis Clean down of build up on weighframe and removal of spillage Inspection and cleaning of idler rolls Zero calibrations Inspect belt tracking Inspect belt wear following work can be carried out less frequently Span calibrations Check mechanical alignment Balance transducers where necessary Check cabling and junction boxes Apart from the general housekeeping of the installation the other important aspect that should be addressed is the record keeping for each installation Most modern Belt Scale electronics store all data in battery backed or non volatile memory however in the case of catastrophic failure this data will probably be lost or not accessible At these times it is essential that accurate records be available for reprogramming purposes Accurate records also allow review of the Belt Scale performance and possible problems that may require attention Belt Scale suppliers will usually be able to provide proper data record sheets that can be used in conjunction with the maintenance program 21 Scale MECHANICAL INSTALLATION NOTE Mechanical misalignment will cause the accuracy and repeatabi
101. wer M8 LOCKNUT M8x40 SOCKET SCREW DRILL THRU 96 9 TAP M8 BOTH ENDS IDLER MOUNTING FRAME DETAIL REVISIONS 18 03 98 ORIGINAL ISSUE UNLESS OTHERWISE STATED DRAWN UNTOLERANCED DIMENSIONS TO BE WITHIN THE LIMITS SHOWN NOMINAL SIZE uP To uP 150 300 1000 ABOVE ABOVE ABOVE asove APPROVED 50 150 300 1000 MACHINING 02 03 05 10 SCALE FABRICATION 05 0 5 1 0 20 2 ASSEMBLIES AUSTRALIA PTY LTD DRAWING No 010 764 431 CHECKED 11 ELECTRONICS STREET EIGHT MILE PLAINS QUEENSLAND 4113 AUSTRALIA NUMBER REV P O BOX 4006 EIGHT MILE PLAINS QUEENSLAND 4113 AUSTRALIA WTE21 1 A Phone 61 7 3841 2844 61 7 3841 0005 ODEL WTE21 CUSTOMER DATE PROJECT o CONVEYOR BELTSCALE ENE CAD FILE oe INSTALLATION GENERAL ARRA N1 TE g IF IN DOUBT ALL DIMENSIONS IN MILLIMETRES and property of WEB TECH AUSTRALIA PTY LID n 01 the confidential ASK UNLESS OTHERWISE SPECIFIED al rh arn eS
102. which is in turn supported at each corner by a transducer Horizontal and transverse restrainers limit the movement of the weighframe in any direction except that perpendicular to the belt line The advantages of both types of design are as follows PIVOTED TYPE FULLY FLOATING TYPE Less Expensive Same design as used in high accuracy static weighing systems Require less transducers Do not use pivots which could influence measurements Can be counterweighted which allows Forces acting on weigh idlers act deadweight of belt and idlers to be directly on tranducers removed Better sensitivity from the Calibration weights represent the transducers same weight regardless of where Less calibration weights required placed on weighframe Generally speaking fully floating multi idler weighframes are normally used for high accuracy weighing applications and pivoted single or multi idler weighframes are used for general purpose weighing applications However similar performance can be achieved by installing two pivoted weighframes in series Weigh Idlers The weighframe supports the belt by means of Weigh Quality idlers The differences between these idlers and standard conveyor idlers are The idler rolls are in line rather than offset The idler rolls are machined concentric to provide 0 13 mm Total Indicated Runout The idler rolls are balanced within 0 011 Nm The idler roll height can be adjusted Weigh Quali
103. xample of an application where both the total and rate are equally important could be a feed conveyor into a coal preparation plant The rate is important as the coal feed into the plant must be maintained at a predetermined setpoint The total input into the plant is important as this determines the yield or quality of the coal when compared to the amount of saleable coal that comes out of the plant A Belt Scale can be installed on the feed conveyor to accomplish both functions All modern Belt Scales calculate both total and rate figures which can be used for whatever purpose Some also have additional features and options such as in built controllers batching facilities and rate alarms which can be used as an adjunct to the primary function It is important when discussing the requirements of a new installation with the Belt Scale supplier to advise him of the intended function of the system to ensure that all the necessary facilities and hardware are available It is also important to discuss what the technical requirements may be for the interface of the Belt Scale with other equipment such as aPLC or controller BELT SCALE SELECTION AND INSTALLATION GUIDE CONT D 2 THEORY OF OPERATION Belt Scales enable material to be weighed on a conveyor whilst in motion A Belt Scale differs from a static weighing system such as a bin weighing system in that the Belt Scale is required to measure two variables The first variable is

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OPERATION &amp; INSTALLATION MANUAL

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OPERATION & INSTALLATION MANUAL