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dpb

On 14-Nov-17 8:32 PM, wrote:
....

OK, why? The fault that the OCD is there to safe is still there.

Precisely _because_ it is a motor circuit and motors are different and
NEC understands that.

It's all in Section 430 but short story is as outlined above; ampacity
of the wire is determined for FLA of the motor; the breaker/fusing is
sized to allow to be able to handle inrush starting current and the LRA
or similar _continuous_ overcurrent protection is _NOT_ provided by the
breaker but the _REQUIRED_ thermal protection for the motor (and thereby
the wiring as well).

IOW, there's a second layer of protection besides the branch circuit
breaker of a "normal" branch circuit you're used to that isn't in the
lighting/general use circuit which relies on the one device for both
functions.

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