Baldor Vector Drives : LUSENET : Elevator Problem Discussion : One Thread

My company is in the process of installing an O'Thompson controller/Series 18H AC Flux Vector Control. I noticed that all the relays on the controller with the exception of car and hall calls were protected by adding noise suppression circuits. (Snubber for AC) and (diode for DC). My question is can the unprotected car and hall relays effect the operation of the Baldor unit?

-- John Fellin (, January 30, 1999


All relays on Thompson controls have noise suppression installed by the factory. If relays or other inductive devices are added to the equipment, proper suppression must be installed. Noise from improperly suppressed relay coils can cause processor re-starts, erroneous faults and other conditions. This can effect the operation of the drive. Please contact O. Thompson Technical Support @ (718) 417-3131 for further assistance.

-- Ian MacMillan (, February 16, 1999.


These Quencharchs...Snubbers or diodes are being used to reduce electrical noise which could interfere with the processors or induce a false low voltage signal in common conduits, travelling cables or troughing...your drive is in proximity of these devices, but wiring is run independent {isolated} from control wiring and I'm sure the installers used adequate suppression and grounding..

-- Joe... (, June 07, 2000.

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