PF525 with RSlogix5000

Hello everyone,

I have a problem with my PF525 overload fault !
It happened to me 3 times in a month !

The motor stopped working and on HMI it showed "motor overload fault" but there is no fault on VFD! it shows everything is normal and I can't reset the fault and start the motor ! I also reboot the PLC and VFD but the alarm was still on HMI! finally I moved the motor by hand accidently and the alarm gone by itself!

any idea if we had an option on PF525 to troubleshoot this problem?

Thanks

You need to look at the PLC program - sounds like the PLC program seals on a fault event but doesn't clear it until it sees the motor RPM feedback (?) is greater than zero.

Check your wiring connections.
Set a trap in your PLC logic to capture a change of state in this input.

As the others have said I would look at the alarm portion of your PLC program. Either the alarm happened and was cleared by the PLC automatically (that's why is it not showing up on the VFD screen) or some other condition caused the alarm to come up. It could be a program bug that is looking at the wrong status bit and is tripping overload alarm erroneously in the PLC/HMI.
You will obviously have to look at the reset portion of the program too.

ben_pordad said:

Hello everyone,

I have a problem with my PF525 overload fault !
It happened to me 3 times in a month !

The motor stopped working and on HMI it showed "motor overload fault" but there is no fault on VFD! it shows everything is normal and I can't reset the fault and start the motor ! I also reboot the PLC and VFD but the alarm was still on HMI! finally I moved the motor by hand accidently and the alarm gone by itself!

any idea if we had an option on PF525 to troubleshoot this problem?

Thanks

Click to expand...

Check parameters A541 and A542. They might be auto resetting the the drive. As the others have mentioned, the rest of the issue sounds like a programming problem caused by a bit not clearing when the fault goes away.

The other thing I would wonder about is WHY the motor has had 3 over current faults in a month. That seems a little excessive.



Will.