VFD problem

Mar 14, 2006 8 Replies

I need help connecting my VFD to a motor.



I connected my VFD (KBAC-27D) to single phase 240V VFD shows code "Undervoltage" I measured voltage between AC lines - 237V, between one AC line and ground - 117V another AC line and ground 117V It's a little less than suppose to be but should be OK I guess. Can anyone shed some light on this problem?



Thanks, Alex


The input voltage magnitude should be fine. All I can think of after scanning the manual is that there are TWO jumpers that need to be set for 115/220V operation. See page 8 of the manual:

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While you're at it, check the 50/60 Hz frequency jumpers as well.

According to Alex :

It is complaining about the third phase terminal, which is not connected to anything. Try jumpering it to the nearest terminal which does have power, and that should eliminate the complaints.

Some VFDs care about this, others do not.

Enjoy, DoN.

Looking at the data sheet he referenced, there are only two line terminals. This is a single-phase only input VFD, which can be set for 120 or 240 V operation.

Jon

So there are -- but this was in a followup by someone other than the original poster, and I had not seen it when I answered.

So it is -- which suggests that either some of the jumpers are not quite set right, or that there are glitches in the power line connection (loose connection) feeding the VFD, causing the undervoltage to appear momentarily.

Enjoy, DoN.

So there are -- but this was in a followup by someone other than the original poster, and I had not seen it when I answered.

So it is -- which suggests that either some of the jumpers are not quite set right, or that there are glitches in the power line connection (loose connection) feeding the VFD, causing the undervoltage to appear momentarily.

Enjoy, DoN.

I talked to manufacturer. They told me that when VFD just pluged in it is fooled and it's OK to start motor. After you start then stop status is OK. Manual never mentioned that.

Alex

D> According to Jon Elson :

Guys,

does anyone know how to make sure motor is compatible with VFD?

Alex

D> According to Jon Elson :

You mean if it is "VFD rated"? No, but mine is not VFD rated and I haven't had any problems. I asked the same question when I installed my VFD and the general answer was "Don't worry about".

Bob

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