Re: OT: Well pump wiring

In article <uGqlg.6500$nS5.4603@trnddc07>, bryan@xxxxxxxxxxxxxxxxxxxxxx
says...
Ned Simmons <news@xxxxxxxxxx> wrote:

There are a couple exceptions to that requirement. The way overcurrent
protection and conductors are figured for motor circuits allows for wire
smaller than you might otherwise expect - see NEC Article 430.

I actually had a copy of the NEC open to Article 430 sitting in my lap when
I read your post, although I'm still having a bit of a time deciphering the
way things are written in there. It reads too much like penal code for
me to feel like I'm fully understanding it.

My simplistic way of thinking about it is that the overcurrent
protection is chosen to avoid nuisance trips (i.e., based on starting
current), while the conductors are sized to carry normal running
(nameplate) current plus some headroom.

See the section on overcurrent protection for transformers if you want
to make yourself dizzy.

Ned Simmons
.

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