OkiePC
Lifetime Supporting Member
Where can I safely measure the full DC BUS on a 3hp 1305 drive?
I can go from DC+ to GND and get half the voltage.
Reason: drive faults for overvolts after accelerating to speed.
We replaced motor (low megohms) and drive and symptoms remain. The motor leads are picking up VFD noise from another drive which runs parallel for about 100', and I think that is causing the fault. I read 40-50VAC of noise on the motor leads with the other drive running.
There is also a load filter on the motor circuit, but bypassing it did not change things either.
We found some significant leakage to ground with the megger on the motor wiring and the guys are chasing that down right now.
Meanwhile, I want to measure the DC bus with my fluke and compare that with parameter 53 (DC Bus volts) to see if the drive is being fooled by noise (like my meter was when trying to ohm the motor leads).
I have never seen a wiring problem cause an overvolt fault. It is driving a 2hp motor turning a conveyor and there is no regeneration going on, plus I changed the decel rate from 1.5 seconds to 10 seconds and it was no help, so I am certain that regeneration is not causing this.
I had no luck finding a service manual for the drive, but if anyone has one, that would be great.
Thanks,
Paul
I can go from DC+ to GND and get half the voltage.
Reason: drive faults for overvolts after accelerating to speed.
We replaced motor (low megohms) and drive and symptoms remain. The motor leads are picking up VFD noise from another drive which runs parallel for about 100', and I think that is causing the fault. I read 40-50VAC of noise on the motor leads with the other drive running.
There is also a load filter on the motor circuit, but bypassing it did not change things either.
We found some significant leakage to ground with the megger on the motor wiring and the guys are chasing that down right now.
Meanwhile, I want to measure the DC bus with my fluke and compare that with parameter 53 (DC Bus volts) to see if the drive is being fooled by noise (like my meter was when trying to ohm the motor leads).
I have never seen a wiring problem cause an overvolt fault. It is driving a 2hp motor turning a conveyor and there is no regeneration going on, plus I changed the decel rate from 1.5 seconds to 10 seconds and it was no help, so I am certain that regeneration is not causing this.
I had no luck finding a service manual for the drive, but if anyone has one, that would be great.
Thanks,
Paul