ABB ACS355 drive problem

Hi,

I have a question outside the plc area, but I thought someone would have an idea.

I was comissioning an ABB ACS355 drive (frequency inverter) with Basic-panel. I entered parameters and tried to manually operate the drive to check the rotation of the motor. When I pressed start button, the drive gives F0016 (earth fault). I checked the motor's and cable's insulation, they're ok. I tried to start drive without motor cable connected and it gave the same fault code.

We discussed with ABB and they said it's warranty issue, so we got a new drive. But it didn't help. New drive gives the same fault code. User manual says that you can disable the earth fault monitoring, but you might lose the warranty by doing that.

Then I had to power up and parametrize ACS 355 drive on different work cite and it runs fine.

So long story short, does anyone had these kind of problems with drives?

I understand that you are getting a Ground Fault on an ACS355 even with no motor leads connected.

My first response would be to check the incoming power. Is it floating, grounded wye, or maybe corner grounded. And, if not grounded wye, have you disconnected the CE filter network?

Let us know. This is a somewhat odd situation that you describe.

Little update to the problem. I tried third drive, same ABB ACS355, and powered it for the first time in different location. As I thought, it worked just fine. So the original location, where I was comissioning the machine has some issues in the power network. Unfortenately we don't have any tool to check the harmonic waves, which would be nice to see. By quick measuring the earth is ok, but voltage in the three phases is a little bit high. We'll keep on checking the problem, as soon as the christmas holidays has passed. Hopefully our client gets a machine with working drive Anyone who reads this thread: Have a merry christmas.

i think it's time to add a drive isolation xfmr, delta primary, Wye or star secondary, ground the center of the star. It will fix any problems related to imbalance or grounding and, lf you get it with taps, you can fix the voltage problems too

viikku said:

Little update to the problem. I tried third drive, same ABB ACS355, and powered it for the first time in different location. As I thought, it worked just fine. So the original location, where I was comissioning the machine has some issues in the power network. Unfortenately we don't have any tool to check the harmonic waves, which would be nice to see. By quick measuring the earth is ok, but voltage in the three phases is a little bit high. We'll keep on checking the problem, as soon as the christmas holidays has passed. Hopefully our client gets a machine with working drive Anyone who reads this thread: Have a merry christmas.

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My advice would be to take heed to DickDV's suggestion, this is more likely an issue with grounding and/or common mode noise issues. An isolation transformer would likely be the answer. If you were using a reactor in front of the drive (and shame on you if not), replace it with the isolation transformer, you would not need both.

Might also possibly be a cable capacitance issue on the way you wired the output though. That happens, especially if you did not use hard metal conduit with proper grounding, or shielded VFD power cable but failed to ground BOTH ends of the shield. That's actually a common mistake because people are used to grounding only ONE end of instrumentation shielded cable, on shielded power cables you must ground BOTH ends.

Excellent comments, jraef, especially concerning power shield grounding

I use KDR series line reactors from Trans-Coil with my VFDs.

http://www.clrwtr.com/TCI-KDR-Line-Reactor.htm

Problem solved. In the original situation we had 0.25kW motor with rated current as 0,4A. The ABB drive propably used this value to calculate earth fault or what ever and caused the problem. When rated current was changed higher the drive worked properly.

viikku said:

Problem solved. In the original situation we had 0.25kW motor with rated current as 0,4A. The ABB drive propably used this value to calculate earth fault or what ever and caused the problem. When rated current was changed higher the drive worked properly.

Click to expand...

How does that explain getting the fault when there was no motor connected?