Recent content by easpe

Hi Does anybody know of a 120v 3 phase protection relay for a 120V 3P open delta with a grounded b phase. The relay operates a automatic transfer backup power system sensing ciruit. There is a Time Mark 263 phase protection relay in the cutler hammer gear now but I am being told it does not...

Use golf cart batteries, more amp hr and deep discharge rated.

Aolalde is correct starting KVA with those motors is to much for a 80 KVA genset. Volt drop is greater then normal design causing contactor coil field to colapse most likely. Good design would suggest different way of starting, differnt pump or bigger generator. However if motors start with ups...

Below is taken from reliance electric, SF and IC are by design and not so much a function of one to the other. At minimum I always use a sf of 1.15 and class f motors. If the motor is in place you can IR and amp it to see if design conditions are exceed. Seen lots of pump installs where class b...

If its not broke don't fix it. As long as there are no problems found caused by harmonics there are no postives to spending money on this issues. As a learning tool you might have a power meter with waveform and harmonic capture installed at the transfer switch load side. Then you could monitior...

What is the acceptable volt drop across a electrical contactor before replacing it. Never seen a standard spec for replacement.