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Doug Miller

In article , wrote:
On Sun, 25 Oct 2009 18:32:00 GMT, (Doug Miller)
wrote:

Hazard?, What hazard? I agree I read two 750w not 3 but the 15a
breaker will still protect the 14 ga wire.
You size the largest load at 125% and the rest at 100%

Code cite on that, please?

I'm specifically questioning the use of the 125% factor for _only a portion_
of a continuous load, as opposed to the _entire_ continuous load.

You are right, I should not have said 125% of the largest load, it is
125% of all of them (16,92a) BUT 240.4(D) applies to the breaker
allowed, not the circuit ampacity, since the 80% rule is already built
into that number.
The ampacity of 14ga wire is 20a, the maximum O/C device is 15a unless
otherwise allowed.(not here)

Look at 210.19 FPN No. 1: "See 310.15 for ampacity ratings of
conductors."

And you're right about that -- I'd forgotten that the 80% rule was already
built in to the overcurrent ratings for 14- and 12-gauge conductors.

BTW these are the kinds of questions that will divide a room full of
inspectors.
The bottom line is a 15a breaker will adequately protect 14ga wire, no
matter what you do with it and those heaters should not trip a 15..

Agreed.