jcole
Senior Member
- Location
- Lawrenceburg, Kentucky
Hell guys and gals.
I had a fault on a powerflex 400 drive called "hardware overcurrent" today. After disconnecting and reconnecting power a fault labeled " UV shorted" came up. "U" and "V" are output terminals for the motor from the drive. The motor does not move at all and the fault happens so fast I cant get a current draw.
I disconnected conductors from drive to motor. I ohmed with VMM phases to phases and phases to ground. Nothing. Then I megged conductors at 1000v the same way and nothing.
I then megged motor to ground at 1000v. Nothing.
I then checked for mechanical overload. Nothing.
I then ohmed phase to phase the motor which has 3 leads. They all were shorted together. But isnt this common for ac induction motors because all you are doing is measuring wire resistance of each coil. Correct?
I connected a motor that is a lot smaller than the one in question and it ran fine.
So I assume the problem is at motor. How would you guys have went about trying to find the problem?
What could possibly be wrong that my measurements are not telling me?
Thanks for replies.
I had a fault on a powerflex 400 drive called "hardware overcurrent" today. After disconnecting and reconnecting power a fault labeled " UV shorted" came up. "U" and "V" are output terminals for the motor from the drive. The motor does not move at all and the fault happens so fast I cant get a current draw.
I disconnected conductors from drive to motor. I ohmed with VMM phases to phases and phases to ground. Nothing. Then I megged conductors at 1000v the same way and nothing.
I then megged motor to ground at 1000v. Nothing.
I then checked for mechanical overload. Nothing.
I then ohmed phase to phase the motor which has 3 leads. They all were shorted together. But isnt this common for ac induction motors because all you are doing is measuring wire resistance of each coil. Correct?
I connected a motor that is a lot smaller than the one in question and it ran fine.
So I assume the problem is at motor. How would you guys have went about trying to find the problem?
What could possibly be wrong that my measurements are not telling me?
Thanks for replies.