background image

CHAPTER 1  

GETTING STARTED

 

1.9 CALIBRATION 

Three calibration processes are available: Zero, Span, and Linearity Calibration.  In addition, a 
Calibration Test and Geographical Adjustment Factor setting are accessible from the CAL 
menu. 

Preliminary Steps

1.  Be sure appropriate calibration masses are available before beginning calibration. 

2.  Be sure the scale base is level and stable during the entire calibration process. 

3.  If LFT is set to On, calibration is unavailable.   

To set LFT to OFF, see Section 1.10, page 1-13.

 

 

Note:

  To use the LFT mode again after turning it off, it is necessary to have the 

Indicator locked and sealed by local Weights and Measures authorities. 

4.  If the Calibration Menu is locked in the Menu Lock submenu, turn it back on: 

– Press and hold 

TARE/Menu

 until 

C.A.L. 

appears, then press 

No

 continuously until: 

– 

L.MENU 

appears.  Press 

Yes

.  

RESET 

appears.  Press 

No

– 

L.CAL 

appears.  Press 

Yes

.  

OFF 

flashes.  Press 

Yes

– Press 

No

 continuously until 

End.LM

 appears.  Press 

Yes

– 

L.Key 

appears.  Press 

No

.  

END

 appears.  Press 

Yes

 to exit menu mode. 

5.  Allow the Indicator to warm up for approximately ten minutes after stabilizing to room 

temperature. 

6.  To abort calibration, press the 

Exit 

button anytime during the calibration process. 

1.8.1 Zero 

Calibration 

Zero calibration uses one calibration point. The zero calibration point is established with no 
weight on the scale. Use this calibration method to adjust for a different pre-load without 
affecting the span or linearity calibration. 

Press and hold 

TARE/Menu

 until 

C.A.L. 

appears, then press 

Yes

.   

(

LFt.NO

 appears briefly before 

C.A.L.

, if the Indicators is not in LFT mode.) 

ZErO

 appears.  Press 

Yes 

to initiate Zero Calibration. 

The display flashes 

and the calibration unit. Press 

Yes 

to establish the 

zero point. 

The display shows 

--C--

 while the zero point is established. 

When zero calibration is completed, the display shows 

dONE

Then the scale exits to the active weighing mode and displays the actual 
weight value. 

Ohaus Corporation  www.ohaus.com 

1-10 

5000 Series T51 Indicator Service Manual 

Summary of Contents for T51P

Page 1: ...SERVICE MANUAL 5000 Series T51 Indicators T51P T51XW Ohaus Corporation 19A Chapin Road P O Box 2033 Pine Brook NJ 07058 2033 973 377 9000 ...

Page 2: ......

Page 3: ...rate at the time of publication but Ohaus Corporation assumes no liability arising from the use or misuse of this material Reproduction of this material is strictly prohibited Material in this manual is subject to change Copyright 2008 Ohaus Corporation all rights reserved TM Registered trademark of Ohaus Corporation ...

Page 4: ......

Page 5: ... Geographical Adjustment Factor 1 13 1 10 RS232 Interface Connection 1 14 1 10 1 Setting Communications Parameters 1 14 1 10 2 Interface Commands 1 15 1 10 3 Output Format 1 15 1 11 Legal For Trade LFT 1 16 CHAPTER 2 TROUBLESHOOTING 2 1 Introduction 2 1 2 2 Visual Inspection 2 1 2 3 Diagnostic Guide 2 2 2 2 1 Diagnosis 2 2 CHAPTER 3 MAINTENANCE PROCEDURES 3 1 Preventive Maintenance 3 1 3 1 1 Preve...

Page 6: ...ng Decreasing Load Test 4 2 5 1 T51P Indicator Housing Internal Parts 5 3 5 2 T51XW Indicator Housing Internal Parts 5 5 A 1 Geographical Adjustment Values A 1 LIST OF ILLUSTRATIONS FIGURE NO TITLE 1 1 Top and Bottom Housing and Rear Panel T51P 1 2 1 2 Top and Bottom Housing and Rear Panel T51XW 1 3 1 3 Printed Circuit Board PCB T51 Indicator 1 4 1 4 Load Cell wiring 1 4 1 5 Open shorted jumpers 1...

Page 7: ...stments Chapter 5 Drawings and Parts Lists Contains exploded views of T51 Indicators identifying all serviceable components Before servicing the indicator you should be familiar with the Instruction Manual which is packed with every indicator 1 2 SERVICE FACILITIES To service an indicator the service area should meet the following requirements Must be protected from electrostatic discharge Should ...

Page 8: ...ons 6 ESD work station or mat 1 3 2 Standard Tools and Test Equipment List 1 Standard Electronics Tool Kit 2 Digital Voltmeter DVM with clip on probes Input impedance of at least 10 megohms in the 1 Volt dc position 3 Soldering Iron solder and flux remover 1 4 Top and Bottom Housing Adjusting Knobs Mounting Bracket Security screw 4 screws Battery Compartment RS232 Connector Power Receptacle Hole p...

Page 9: ...ing Bracket 4 hex head bolts RS485 422 Scale 1 RS232 Scale 2 Relay Option Cable Load Cell Cables RS232 Cable Power Cord Security screw location Figure 1 2 Top and Bottom Housing and Rear Panel T51XW 5000 Series T51 Indicator Service Manual 1 3 Ohaus Corporation www ohaus com ...

Page 10: ...5V DC Load Cell Drive Up to 4 x 350 ohm load cells Load Cell Input Sensitivity Up to 3mV V Stabilization Time Within 2 seconds Auto Zero Tracking Off 0 5 1 or 3 divisions Zeroing Range 2 or 100 of capacity Span Calibration 1 kg or 1 lb to 100 capacity Interface RS232 optional Com2 either RS232 or RS422 485 Overall Dimensions W x D x H in mm 10 2 x 2 7 x 6 5 260 x 71 x 166 10 3 x 3 0 x 5 8 262 x 76...

Page 11: ...front housing forward Below is a diagram of the T51 s Main PCB with connectors jumpers terminals and switches indicated Figure 1 3 Printed Circuit Board PCB T51 Indicator Power Supply connector Battery connector J2 T51P only Alternate Load Cell Terminal J4 Sense Jumper W1 Sense Jumper W2 Security Switch SW2 RS232 Terminal J7 T51XW only External Input Terminal Block COM2 Connector J8 Optional RS232...

Page 12: ...S422 485 The optional interface is available separately with its own instructional manual for installation and configuration TABLE 1 2 T51P RS232 PIN CONFIGURATION 1 2 3 4 5 6 7 8 9 Figure 1 6 RS232 Pins T51P Pin Connection 1 N C 2 TXC 3 RXD 4 N C 5 GND 6 N C 7 CTS 8 RTS 9 N C TABLE 1 3 T51XW RS232 TERMINAL CONFIGURATION Figure 1 7 RS232 Terminal T51XW Pin Connection 1 RTS 2 TXD 3 RXD 4 CTS 5 GND ...

Page 13: ...r can operate for up to 80 hours on battery power During battery operation the battery charge symbol indicates the battery status The indicator will automatically turn off when the batteries are fully discharged 0 5 charged 5 25 charged 26 50 charged 51 75 charged 76 100 charged Figure 1 8 Battery charge symbol 1 8 OVERVIEW OF THE CONTROLS Capacity label window Under Accept Over LEDs Stability Zer...

Page 14: ...ects the current setting on the display and advances to the next available setting Increments the value Back Moves back to previous menu item Decrements the value Exit Exits the User menu Aborts a calibration in progress 1 8 3 Menu Setup To enter the Menu Mode press and hold the TARE Menu button until MENU appears on the display The first upper level menu appears on the display Use Yes No Back and...

Page 15: ...DE NAME LAYOUT FORMAT FEED LIST END PRINT1 PRINT 2 COM 1 COM 2 I O LOCK MENU LOCK KEY END RESET STABLE ONLY2 AUTO PRINT CONTENT RESULT GROSS NET TARE HEADER USER ID PROJECT ID SCALE ID DIFFERENCE DATE TIME INFO MODE NAME LAYOUT FORMAT FEED LIST END PRINT2 RESET BAUD PARITY STOP BIT HANDSHAKE ALT COMMAND PRINT TARE ZERO END COM1 RESET BAUD PARITY STOP ADDRESS3 HANDSHAKE ALT COMMAND PRINT TARE ZERO ...

Page 16: ...es Press No continuously until End LM appears Press Yes L Key appears Press No END appears Press Yes to exit menu mode 5 Allow the Indicator to warm up for approximately ten minutes after stabilizing to room temperature 6 To abort calibration press the Exit button anytime during the calibration process 1 8 1 Zero Calibration Zero calibration uses one calibration point The zero calibration point is...

Page 17: ...tion point Place the specified weight on the scale and press Yes To choose a different span point press No to increment the selections or Back to decrement the selections When the desired value is displayed place the specified weight on the scale and press Yes The display shows C while the span point is established The display flashes 0 With no weight on the scale press Yes to establish the zero p...

Page 18: ...calibration point and calibration unit Place the specified weight on the scale and press Yes To choose a different full point or calibration unit kg or lb press No to increment the selections or Back to decrement the selections When the desired value is displayed place the specified weight on the scale and press Yes The display shows C while the full calibration point is established The display fl...

Page 19: ...e example shows a 0 010 kg difference If printing is enabled the result of the Calibration Test is printed After 5 seconds Calibration Test ends the scale returns to the active weighing mode and displays the current weight 1 9 5 Geographical Adjustment Factor The Geographical Adjustment Factor GEO is used to compensate for variations in gravity To determine the GEO factor that corresponds to your ...

Page 20: ...st 9600 then 300 600 1200 2400 4800 and 9600 again Press Yes when the desired setting appears bAUd appears again Press No 4 PAritY appears Press Yes The default Parity setting 8 NONE appears To change the setting press No The menu cycles to the next setting each time you press No first 7 Even then 7 Odd 7 None and 8 None again Press Yes to accept a setting PAritY appears again Press No 5 StOP appe...

Page 21: ...LFT is set ON Enter Header line where x line number 1 to 5 text header text up to 24 alphanumeric characters H x text Esc R Global reset to reset all menu settings to the original factory defaults NOTES 1 Commands sent to the Indicator must be terminated with a carriage return CR or carriage return line feed CRLF 2 Alternate command characters may be defined by the user 3 Data output by the Indica...

Page 22: ...d TARE Menu until C A L appears then press No 2 S E t U P appears Press Yes Then press No until LFt appears Press Yes 3 OFF appears Press Yes 4 LFt appears again Press No Then press Exit to return to the current application mode 5 It is now possible to use the above mentioned menus After the Security Switch has been turned off before it can be used in a trade approved application it must be inspec...

Page 23: ...cracks on corners which may suggest the unit was dropped 2 Open the Indicator by removing the four screws in the rear housing Be careful not to stretch the cables that connect the main Printed Circuit Board PCB to the outlets RS232 and Load Cell ports and power supply 3 Examine the top of the main PCB for cracks or signs of corrosion 4 If it appears corrosion may have affected the board examine th...

Page 24: ...ents 2 3 1 Diagnosis 1 Isolate and identify the symptom 2 Refer to Table 2 1 Diagnostic Guide and locate the symptom 3 Follow the suggested remedies in the order they appear 4 Perform the indicated checks or see the appropriate section of the manual 5 Repair or replace the defective part NOTE If more than one symptom is observed approach one area at a time and remember that the symptoms may be int...

Page 25: ...vironment Perform calibration Move scale to suitable location Unable to calibrate Unstable environment Incorrect calibration mass Lock Calibration Menu set to On LFT menu set to On Main PCB failure Move the scale to suitable location Use correct calibration mass Set Lock Calibration Menu to Off Set LFT menu to Off Replace Main PCB Cannot display weight in desired weighing unit Unit not set to On E...

Page 26: ...8 6 Weight exceeds six digits Display overflow Reduce load on scale Error 9 5 Calibration data not present Calibrate scale CAL E Calibration value outside allowable limits Repeat calibration using correct calibration weights LOW REF WT The average piece weight of the parts is too small warning Increase sample size Add additional samples or continue to weigh with less accurate results REF WT Err Re...

Page 27: ...e using a cloth dampened with a mild detergent 3 For the T51XW use appropriate cleaning solutions for the stainless steel Indicator housing and rinse with water CAUTION DO NOT USE CHEMICAL CLEANERS OR SOLVENTS OF ANY TYPE SOME CLEANERS ARE ABRASIVE AND MAY AFFECT THE SCALE S FINISH 4 Check the Power Cord for broken or damaged insulation 5 Make a visual inspection for faulty connectors wiring and l...

Page 28: ...eads 6 On the T51P remove the hex screws connecting the RS232 Interface port to the Bottom Housing so the port will clear when the PCB is lifted out 7 Remove the four screws from the PCB and on the T51XW a fifth securing the grounding cable to the PCB on the lower left CAUTION When handling the PCB grasp it by the edges only Always use an anti static kit Do not touch the foil side Static discharge...

Page 29: ...ne connected to the Membrane Switch and the other to the Main PCB 5 Lift out the Display PCB 6 Connect the ribbon cables to the replacement Display PCB and carefully position the board over the screw holes Insert the screws and tighten them 7 On the T51XW carefully re position the Main PCB over its screw holes in the Top Cover Re insert and tighten the screws 8 On the T51XW reconnect the cables re...

Page 30: ...refully clean the Top Housing Membrane Switch area removing all traces of adhesive The best method is to use a flat razor blade 5 Remove the protective backing from the back of the new Membrane Switch carefully position it on the Top Cover starting at the bottom of the cover Use a rolling motion to smooth the Membrane Switch into position 6 Reconnect the cable removed in Step 2 7 Close the Housing...

Page 31: ... cases the AC Adapter supplied with the Indicator may have become defective 1 Connect a functioning AC Adapter to the Indicator power plug 2 Plug the AC Adapter into a suitable power source 3 With the Indicator connected to an appropriate power supply press the ON ZERO Off button The Indicator performs a self test indicates the software revision and then goes into weighing mode 4 If all of the dis...

Page 32: ...tor to zero Power on the Indicator Perform a Span Calibration with zero at the simulator s zero setting and 100 capacity at the simulator s 2 0 milli volt setting 2 Following calibration check that the Indicator s display reading is stable at each simulator level up to the maximum set in the calibration If the readings are stable the Indicator is functioning properly 4 5 Calibration Retention Test...

Page 33: ...ghly checked after the replacement is made The balance MUST meet the parameters of all applicable specifications in this manual If further technical information is needed please contact your local Ohaus distributor or Ohaus Corporation www ohaus com 19A Chapin Road P O Box 2033 Pine Brook NJ 07058 2033 USA Tel 973 377 9000 Fax 973 593 0359 In the United States call toll free 800 526 0659 between 8...

Page 34: ...ARTS LISTS DIAGRAMS 5 1 5000 SERIES T51P INDICATOR HOUSING INTERNAL PARTS Figure 5 1 Series 5000 T51P Indicator Housing Internal Parts Ohaus Corporation www ohaus com 5 2 5000 Series T51 Indicators Service Manual ...

Page 35: ... 7 Display PCB 8 Battery Cover 9 NiMH Battery 10 Rear Housing 11 Knob Kit set of 2 12 Wall Mount Kit 13 Battery Guide 14 Cable Kit 15 PCB Power Supply 16 Power Supply PCB Cover 18 I O Fitting 20 Hardware Kit 21 I O Filler Plug 22 Recharge PCB 23 RS422 485 Interface Kit Accessory 23 RS232 Interface Kit Accessory 24 Relay PCB Cover 25 Relay Kit Accessory 26 Main PCB 70 Line Cord 5000 Series T51 Indi...

Page 36: ...RTS LISTS DIAGRAMS 5 2 5000 SERIES T51XW INDICATOR HOUSING INTERNAL PARTS Figure 5 1 Series 5000 T51XW Indicator Housing Internal Parts Ohaus Corporation www ohaus com 5 4 5000 Series T51 Indicators Service Manual ...

Page 37: ...PCB 9 NiMH Battery 10 Rear Housing 11 Knob Kit Set of 2 12 Wall Mount Kit 14 Cable Kit 15 PCB Power Supply 16 Cover Power Supply PCB 17 I O Fitting 18 I O Fitting 19 Cable Mounts Internal 20 Hardware Kit 21 I O Fitting 22 Recharge PCB 23 Accessory RS422 485 Interface Kit 23 Accessory RS232 Interface Kit 24 Cover Relay PCB 25 Accessory Relay Kit 26 Main PCB 70 Line Cord 5000 Series T51 Indicators S...

Page 38: ...CHAPTER 5 PARTS LISTS DIAGRAMS Ohaus Corporation www ohaus com 5 6 5000 Series T51 Indicators Service Manual ...

Page 39: ... 17 17 18 18 19 19 20 20 21 21 22 22 04 05 05 06 06 07 07 08 08 09 09 10 10 11 11 12 12 13 13 14 14 15 15 16 16 17 17 18 18 19 19 20 20 21 21 22 04 04 05 05 06 06 07 07 08 08 09 09 10 10 11 11 12 12 13 13 14 14 15 15 16 16 17 17 18 18 19 19 20 20 21 21 03 04 04 05 05 06 06 07 07 08 08 09 09 10 10 11 11 12 12 13 13 14 14 15 15 16 16 17 17 18 18 19 19 20 20 21 03 03 04 04 05 05 06 06 07 07 08 08 09 ...

Page 40: ...4 66 24 67 57 67 57 69 35 69 35 71 21 71 21 73 16 73 16 75 24 75 24 77 52 77 52 80 56 80 56 85 45 85 45 90 00 23 23 24 24 25 25 26 26 27 27 28 28 29 29 30 30 31 22 23 23 24 24 25 25 26 26 27 27 28 28 29 29 30 30 22 22 23 23 24 24 25 25 26 26 27 27 28 28 29 29 30 21 22 22 23 23 24 24 25 25 26 26 27 27 28 28 29 29 21 21 22 22 23 23 24 24 25 25 26 26 27 27 28 28 29 20 21 21 22 22 23 23 24 24 25 25 26...

Page 41: ......

Page 42: ... 80252587 P N 80252587 SERVICE MANUAL 5000 SERIES T51 INDICATORS ...

Reviews: