KERN PNJ Service Manual Download Page 1

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KERN & Sohn GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]

Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com

Servicemanual

Precision balances

KERN PNJ/PNS

Version 1.1

03/2020

Summary of Contents for PNJ

Page 1: ...Sohn GmbH Ziegelei 1 D 72336 Balingen E Mail info kern sohn com Tel 49 0 7433 9933 0 Fax 49 0 7433 9933 149 Internet www kern sohn com Servicemanual Precision balances KERN PNJ PNS Version 1 1 03 202...

Page 2: ...7 1 Adjustment with internal weight only models PNJ 12 7 2 Adjustment with external weight only models PNS 13 7 3 CALIBRATION OF BUILT IN WEIGHT REFCAL 15 7 4 Resetting address data and linearity cal...

Page 3: ...cation will result in a loss of the type approval After successful repair the balance will have to be reverified before it can be used again in a statutorily regulated field Detailed instructions abou...

Page 4: ...ction Turn on off Transfer weighing data via interface Exit menu back to weighing mode Save settings back to weighing mode Switch over weighing unit Menu access longer pressing of the button Scroll fo...

Page 5: ...s just processing a function CAL Illuminates and flashes during an adjustment process Brackets for identifying non verified digits only verified models Capacity display The bar graph display moves fro...

Page 6: ...y of 620 g or less Square pan for capacity of 1200 grams or more Remove the hexagon head bolts attached in two locations and then remove the protector and dust cover Circle pan for capacity of 620 gra...

Page 7: ...tapping screws attached in two locations and then remove the case case Tabs inside Notches Tapping Screw 4 mm x 10 mm long 3 3 Attaching the case Attach the case by performing the reverse of the proce...

Page 8: ...Check the weighing pan 2 Inspect the inside of scale 3 Replace the mechanical unit 4 Reconsider the installation location and response speed appears on display before Capacity 9d is reached 1 Sum of...

Page 9: ...mple weight is too light Number of weights in the percentage weighing mode 1 Check the sample weight Display shows I Err 1 Balance weight was lighter than 50 of capacity during span calibration 1 Chec...

Page 10: ...r NO Connectors ar inserte Check memory content 0 err u err Reset address data Not good Return to initial inspection Check output waveforms OK Tunning fork assy failure FAULTY Replace tunning fork ass...

Page 11: ...ion of the electrical section remove the AJDP circuit board and check the board and check at CN1 CN4 TP4 and TP6 1 Check the supply voltage of TP0 CN1 5 7 to 6 3 V 2 Check supply voltage within the ci...

Page 12: ...s at the same time The motor noise of the loading system for the internal adjustment weight can be heard the internal adjustment is started After successful adjustment the balance automatically return...

Page 13: ...is displayed With pressed TARE key press the F key then release both keys at the same time Ensure that there are no objects on the weighing pan With display on FS place the required adjustment weight...

Page 14: ...errupted The balance returns to weighing mode At the models with internal adjustment weight KERN PNJ the adjustment with external weight is not possible The following error messages may be displayed d...

Page 15: ...E Following does not describe the procedure of ordinary span adjustment This is the procedure of Calibration of the built in weight of AJH CE scales lt is necessary to adjust the linearity of the scal...

Page 16: ...PNJ_PNS SH e 2011 16...

Page 17: ...of address data see the data attached on the reverse side of the scale Span calibration Performance check Coefficient memories address data have changed by noises or static electricity Entry of addres...

Page 18: ...the mechanical unit is replaced new data sheet shall cover the old one Data sheet 7 5 2 How to read the data sheet Tuning fork No Program No Address from the left 00 to 09 Address from the left 0A to...

Page 19: ...nd release both On 0 6 on 0 starts blinking Zero point calibration 7 Follow the steps at the display On 1 to on 4 8 After busy appears the sclae shifts to the weighing mode 9 Turn off the scale 10 Tur...

Page 20: ...PNJ_PNS SH e 2011 20 7 7 Corner Error Adjustment Remove the case and remove the boarder holder assy Reattach the weighing pan and the pan base and then use the adjuster to make them level...

Page 21: ...21 PNJ_PNS SH e 2011 Turn the adjusting bolts to adjust the corner error referring to following illustrations After adjustment apply screw locking glue to the adjusting bolts Describtion...

Page 22: ...assy and then bring the right and left stoppers into slight contact In the stopper adjustment use a tool to access the stoppers from the side of the pan base when a circle pan for capacity of 620 gram...

Page 23: ...emove the case Flip the board holder assy over be carful not to damage the liquid crystal surface of the display board LF board cable IF board cable AJDP circuit board failure Removal of AJDP circuit...

Page 24: ...ldered onto the AJDP circuit board AJDP circuit board White wire Shield wire Black wire Tuning fork cable Remove the two tapping screws and then remove the AJDP circuit board from the board holder Tap...

Page 25: ...ard Install the AJDP circuit board in the board holder Board holder assy Tapping screw 3 mm x 8 AJDO board assy Projections Perform final tightening while holding down the board The LCD and the window...

Page 26: ...ing fork assy cable onto the AJDP circuit board 3 Connect the cables to CN1 and CN4 on the AJDP circuit board 4 Fix the board holder assy on the chassis in place Insert the chassis tabs into the notch...

Page 27: ...AJDP circuit board 2 Remove M4 conical nuts attached at four locations and then remove the mechanism unit assy from the mechanical unit base of the chassis assy Chassis assy Mechanism unit assy Conic...