Recent Job Report #2- ALLEN BRADLEY 1391 AC Servo Controller Repair


Last week, we received in an Allen Bradley 1391B-AA45 AC servo controller for repair.  We have repaired hundreds of these units and have a high rate of success.  This customer, in the automotive industry, said they needed it back in a week, if that was possible.  We had it back to them in 3 days.  We cleaned and baked unit, replaced fan and several components at the board level and more.  If you need a repair of your servo drive or other automation equipment, please call 1(888) 706-5263 for immediate service.  To browse our inventory, go to  Enjoy!

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Very contaminated Allen Bradley servo controller.   Technician Adam H. removes logic board

                                                                                   during disassemble.

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Removing driver board.                                            Heavily contaminated Driver board.

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Removal of DC bus capacitor.      High current area with heavy contamination, on IGBT’s as well.


Full disassemble of unit.                                                          Testing driver board before cleaning.

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Discuss troubleshooting using schematics.    Contaminated fan leads to many problems: Fan


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Adam cleans logic board.                                              Cleaning driver board.

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Baking components to eliminate moisture.  New components installed, including preventative

                                                                            replacement of aged or worn.



Soldering in new resistors.                                                             Installing DC bus capacitor.



Driver board mount  and install.                                 Finishing assembly of drive housing.



Final logic board connect and mount.        Test cart connection for final run test and evaluation.

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Successful run test with Allen Bradley servo motor.        Drive is ready.

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                          Call Repair Zone 1-888-706-5263

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  1. Victor,

    Hello, we have received your request but were unable to retrieve any contact information for you. Please call 1-888-706-5263 or email us at so we can properly assist you.

    Thank You,

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