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Effect of higher frequencies on breaker and CT

Effect of higher frequencies on breaker and CT

Effect of higher frequencies on breaker and CT

(OP)
Hi All,

I have a feeder feed by Variable Frequency Drive (VFD)of 60-200HZ.
I have breaker and CT after VFD. Is there any effect on CT and breaker when frequency changes from 60 to 200hZ.

RE: Effect of higher frequencies on breaker and CT

Don't do that.  Just rely on the protections of the VFD.  Most relays won't work above 75Hz, if even that high.  The VFD will do a perfectly goo job.  Breaker after the VFD is just asking to fry the VFD.

RE: Effect of higher frequencies on breaker and CT

CT performance improves with frequency up to a certain point. Normally that's around the 30th harmonic or so.

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