well, it either going to work or make a loud boom

ganutenator

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got a 212 drive connected to a weird motor. drive faulting on mtr phase loss. rang it alll out. it all looks good. about to turn motor phase loss off. it probably going to go boom, huh.
 
what brand and model of drive?
what brand and model of motor?

I ask because I am familiar with some European type motors that require L1 to L1, L2 to L2 and L3 to L3 motor connections or else they burn up.

regards,
james
 
In a former life I was in the break room listening to another tech tell about the rough day he was having. He had to replace 4 different motors in one 12 hour shift. He was remarking on his bad luck getting the rotation right.

He said "You would think that since there is a 1 in 3 chance of getting the direction right, at least one of those motors would have been right on the first try, but NO, I had to swap phases on every one of them."

I remarked, "Actually, you have a one in two chance, forward or reverse"

Without missing a beat, he piped up, "No. It's 1 in 3. Forward, reverse, or not at like like that 25 horse I have to go replace again right after break."
 
Different manufactures measure motor phase loss in different ways and in my experience they do not always take the most direct route. Because of this local conditions can fool the drive. Electrical noise, loose couplings, reciprocating motion, even just a motor that is wound a little "off".

You said that you "rang it out", did this also include measuring the current on each phase, and was the current balanced? If so, then I would say you are okay to disable the phase loss detection. If you have a mis-wire, as in the case that James and pal mentioned, it would show up as a current imbalance.

Several years ago I had a AB motor that had two of the coil leads mis-marked, the VFD faulted for phase loss. Measuring the current was the first clue to the cause and then ringing out each coil independently pinpointed it.

Hope this helps.
 
Mad_poet,

All I know it that Desoutter and several other companies require correct phasing as I noted. After burning up the first motor and contacting the company, we phased each motor from then on.

james

That's interesting. I've never come across a motor that "literally" could only be phased one way. Is my assumption correct that the motor you are referring to can only run in one direction?
 
That's interesting. I've never come across a motor that "literally" could only be phased one way. Is my assumption correct that the motor you are referring to can only run in one direction?

I've seen it in blowers that have an anti-backup bar attached to the blower shaft. But that's on the blower, the motor could care less.

(old) punch presses are the same way, get it wrong and you will shear off some bolts (had that happen once).
 

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