OHAUS T71P Service Manual Download Page 1

Page: 1 / 48

SERVICE MANUAL
7000 Series

T71 Indicators

T71P T71XW

Ohaus Corporation 19A Chapin Road, P.O. Box 2033, Pine Brook, NJ 07058-2033 (973) 377-9000

Summary of Contents for T71P

Page 1: ...SERVICE MANUAL 7000 Series T71 Indicators T71P T71XW 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: ...pan Calibration 1 14 1 8 3 3 point Linearity Calibration 1 15 1 8 4 5 point Linearity Calibration 1 16 1 8 5 Calibration Test 1 17 1 8 6 Geographical Adjustment Factor 1 17 1 9 RS232 Interface Connection 1 18 1 9 1 Setting Communications Parameters 1 18 1 9 2 Interface Commands 1 19 1 9 3 Output Format 1 20 1 10 Legal For Trade LFT 1 21 CHAPTER 2 TROUBLESHOOTING 2 1 Introduction 2 1 2 2 Visual Ins...

Page 6: ...de 2 3 4 1 Increasing Decreasing Load Test 4 2 5 1 T71P Indicator Housing Internal Parts 5 3 5 2 T71XW 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 T71P 1 2 1 2 Top and Bottom Housing and Rear Panel T71XW 1 3 1 3 Printed Circuit Board PCB T71 Indicator 1 5 1 4 Load Cell Terminal Blocks J4...

Page 7: ...g Contains an operational test segment display test performance tests and adjustments Chapter 5 Drawings and Parts Lists Contains exploded views of T71 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...

Page 8: ...rface 4 RS232 Interface cable 5 Data Printer for use with RS232 communications 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 Figure 1 1 Top and Bottom Housing and Rea...

Page 9: ...3 Ohaus Corporation www ohaus com 1 4 Top and Bottom Housing Figure 1 2 Top and Bottom Housing and Rear Panel T71XW Adjusting Knobs Mounting Bracket 4 hex head bolts RS232 Cable Security screw Power Cord RS232 Scale 2 RS485 422 Scale 1 Load Cell Cables Relay Option Cable ...

Page 10: ...IP66 Load Cell Excitation Voltage 5V DC Load Cell Drive Up to 8 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 Interfaces RS232 External Input optional Com2 Overall Dimensions W x D x H in mm 10 2 x 2 7 x 6 6 260 x 71 x 168 1...

Page 11: ...ase s Load Cell The T71P has a circular connector jack on its Bottom Housing The white plastic six wire plug connects to the Scale 1 Load Cell Connector J14 See Figure 1 3 Attach a base without a circular connector to one of the Load Cell Terminal Blocks on the Main PCB Pass the load cell cable through a Cable Gland see Figure 1 1 and attach it to Terminal Block J4 or Terminal Block J7 See Figure ...

Page 12: ...4 GND 5 Signal 6 Sense 7 Excitation Figure 1 6 Open shorted jumpers 1 6 3 RS232 Interface The T71P has a built in RS232 Interface a standard 9 pin D style female connector on the back of the T71P Housing In addition each model T71P and T71XW has an optional COM2 connector which can be either RS232 or RS422 485 The optional interface is available separately with its own instructional manual for ins...

Page 13: ...arged 76 100 charged The T71P indicator can also be operated on six alkaline batteries not supplied when AC power is not available It will automatically switch to battery operation if there is power failure or the power cord is removed The indicator can operate for up to 80 hours on battery power During battery operation the battery charge symbol indicates the battery status The indicator will aut...

Page 14: ... off Units Changes the weighing unit Mode Allows changing the application mode Press and hold allows scrolling through modes Menu Enter the User menu Edit Enable editing the current library record Menu Function Short Press Yes Accepts the current menu or setting No Advances to the next menu or menu item Rejects the current setting on the display and advances to the next available setting Increment...

Page 15: ...nd Scale 2 Info Show the Accumulation statistics on the display Change the polarity of the displayed value 1 7 5 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 Exit to navigate in Menu Mode Yes Allows entry into the displayed menu Accepts the displayed setting and advances...

Page 16: ... ON OFF CUSTOM 2 OFF ON SET FACTOR EXP LSD COUNT ON OFF APW OPTIMIZE ON OFF SETUP END SETUP RESET YES NO LFT OFF ON BEEPER VOLUME OFF LO HI BEEPER SIGNAL OFF ACCEPT UNDER OVER UND OVR KEY BEEP ON OFF BACK LIGHT OFF ON AUTO AUTO 5 SEC 30 SEC SHUT OFF OFF SET 1 SET 2 SET 5 GROSS INDICATOR OFF Gross Brutto N GMP PROJ ID USER ID SET SET END GMP N Y DATE set type TYPE MDY DMY YMD SET RESET YES NO SCALE...

Page 17: ... ON I O OFF ON LOCK KEY OFF OFF ON END LOCK KEY N Y RESET YES NO ZERO OFF ON PRINT OFF ON UNIT OFF ON FUNCTION OFF ON MODE OFF ON TARE OFF ON MENU OFF ON Info Off On App Mode Off On Name Off On PRINT 2 AUTO PRINT OFF On Stable Interval Continuous INTER 1S 1M 1H Load Load Zero On Stable RESET YES NO STABLE ONLY 2 OFF ON Accept COM1 BAUD PARITY RESET YES NO 300 9600 19200 7EVEN 7ODD 7NoP 8NoP HandSh...

Page 18: ...h German French and Italian To change the menu language press and hold TARE Menu until MENU appears When the button is released the Legal For Trade status is displayed followed by the first menu To navigate the menus press No to move to the next menu or Back to move to the previous one Press Yes to enter the displayed menu Press Exit to immediately leave a menu and return to weighing mode The map ...

Page 19: ...CALIBRATION Press No until MENU MENU LOCK appears Press Yes L MENU RESET appears Press No L MENU LOCK CAL appears Press Yes L CAL OFF flashes Press Yes Then Press Exit to return to weighing mode Open the Indicator and put the Security Switch on the Main PCB in the OFF position 5 Allow the Indicator to warm up for approximately five minutes after stabilizing to room temperature 6 To abort calibrati...

Page 20: ...l LFT OFF flashes and CALIBRATION appears Press Yes CAL ZERO appears Press No CAL SPAN appears Press Yes SPAN and the current unit of measure and Span calibration point flash Note To change the span calibration point press No and enter the value using the keypad Then press Yes To change the calibration unit of measure press No to alternate between kg and lb Place the specified calibration weight o...

Page 21: ...and hold TARE Menu until LFT OFF flashes and CALIBRATION appears Press Yes CAL ZERO appears Press No CAL SPAN appears Press No 3 PT LINEAR appears With no load on the scale press Yes The display shows the current full load calibration point and calibration unit of measure Note To change the full load calibration point press No and enter the desired value using the keypad Then press Yes To change t...

Page 22: ...load calibration point press No and enter the desired value using the keypad Then press Yes To change the calibration unit of measure press No to alternate between kg and lb Place the specified full load calibration weight on the scale and press Yes The display shows C followed by the 3 4 load calibration point Place the specified 3 4 load calibration weight on the scale and press Yes The display ...

Page 23: ...isplay shows T followed by difference between the calibration weight and the stored calibration data After five seconds the display returns to the current application mode 1 8 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 location see Appendix A Note Changing the GEO Facto...

Page 24: ...o change the setting press No The menu cycles to the next setting each time you press No first 9600 then 300 600 1200 2400 4800 and 9600 again Press Yes when the desired setting appears COM 1 bAUd appears again Press No 4 COM 1 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 th...

Page 25: ...al 1 3600 sec Z2 Same as pressing Zero button T2 Same as pressing Tare button xT Download Tare value in grams positive values only Sending 0T clears tare if allowed PU Print current unit g kg lb oz lb oz xU Set scale to unit x 1 g 2 kg 3 lb 4 oz 5 lb oz PV Version print name software revision and LFT ON if LFT is set ON H x text Enter Header line where x line number 1 to 5 text header text up to 2...

Page 26: ...cters If the value is negative the character is located at the immediate left of the most significant digit 4 The Unit field contains the unit of measure abbreviation up to five characters 5 The Stability field contains the character if the weight reading is not stable The Stability field and the following Space field are omitted if the weight reading is stable 6 The G N field contains the net or ...

Page 27: ...hen set the LFT menu item to OFF as follows 1 Press and hold TARE Menu until MENU LFT OFF appears briefly followed by MENU CALIBRATION 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 abovementioned menus After the Security S...

Page 28: ...CHAPTER 1 GETTING STARTED Ohaus Corporation www ohaus com 1 22 7000 Series T71 Indicator Service Manual ...

Page 29: ... base damage from liquids 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 that corrosion may hav...

Page 30: ...ents 2 2 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 31: ...ion Unstable environment 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 ...

Page 32: ...cale Error 8 4 Weight reading below Underload limit Add load to scale Recalibrate scale Error 8 6 Weight value exceeds six digits Use more appropriate unit of measure Reduce load on scale displayed Busy message Displayed during tare setting zero setting printing If this message persists it usually indicates the reading is not stable Correct the instability NO displayed The action is not allowed Do...

Page 33: ...a cloth dampened with a mild detergent 3 For the T71XW use appropriate cleaning solutions for the stainless steel Indicator housing and rinse with water Dry thoroughly 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 wirin...

Page 34: ...ews and remove the leads 6 On the T71P 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 T71XW a fifth securing the grounding cable to the PCB on the lower left CAUTION When handling the PCB grasp it by the edges only Do not touch the foil side Static discharge may damag...

Page 35: ...Switch 5 Gently remove the two ribbon cables one connected to the Membrane Switch and the other to the Main PCB Avoid bending the pins 6 Connect the ribbon cables to the replacement Display PCB and position the board over the screw holes Insert the screws and tighten them 7 Carefully re position the Main PCB over its screw holes in the Top Cover Re insert and tighten the screws 8 Reconnect the cab...

Page 36: ...r starting at the bottom of the cover Use a rolling motion to smooth the Membrane Switch into position 4 Carefully re position the Main PCB over its screw holes in the Top Cover Re insert and tighten the screws 5 Reconnect the cables removed in Steps 4 and 5 of Section 3 2 1 6 On the T71P re insert the hex screws connecting the RS232 Interface port to the Bottom Housing 7 Close the Housing and re ...

Page 37: ...ve 1 Plug the AC Adapter or line cord into a suitable power source 2 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 3 If all of the displays appear normal in this test continue with the next test If the display did not appear check that the AC input is good ...

Page 38: ...1 Set the simulator 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 Calibratio...

Page 39: ...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 40: ...S T71P INDICATOR HOUSING INTERNAL PARTS 11 22 13 8 12 14 21 6 4 18 4 70 23 15 25 16 7 3 1 2 5 24 20 26 10 9 Figure 5 1 Series 7000 T71P Indicator Housing Internal Parts Ohaus Corporation www ohaus com 5 2 7000 Series T71 Indicators Service Manual ...

Page 41: ... 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 AC Relay Kit Accessory 26 Main PCB 70 Line Cord 7000 Series T71 Ind...

Page 42: ...RTS LISTS DIAGRAMS 5 2 7000 SERIES T71XW INDICATOR HOUSING INTERNAL PARTS Figure 5 1 Series 7000 T71XW Indicator Housing Internal Parts Ohaus Corporation www ohaus com 5 4 7000 Series T71 Indicators Service Manual ...

Page 43: ...CB 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 AC Relay Kit 26 Main PCB 70 Line Cord 7000 Series T71 Indicators...

Page 44: ...CHAPTER 5 PARTS LISTS DIAGRAMS Ohaus Corporation www ohaus com 5 6 7000 Series T71 Indicators Service Manual ...

Page 45: ... 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 46: ...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 47: ......

Page 48: ... 80252588 P N 80252588 SERVICE MANUAL 7000 SERIES T71 INDICATORS ...

Search results

Summary of Contents for T71P

Reviews:

Related manuals for T71P

Brands by name

Popular brands

OHAUS T71P, Service Manual

Search results

Summary of Contents for T71P

Reviews:

Related manuals for T71P

Brands by name

Popular brands