In article , "Lew Hodgett" wrote:
Doug Miller wrote:
+++++

"When a c'bkr is in a panel, it is derated by 20% to handle the panel heat
generated by adjacent c'bkrs.." -- nonsense. Circuit breakers are *required*
by Code to be placed in a panel or other similar fixture [Article 240.30] and
no derating is applied for doing so.

Name plate ratings of molded case thermal-magnetic c'bkrs are for bkrs in
free air.

As soon as the bkr is placed in an enclosure, detating applies.

Got a Code cite for that?

I didn't think so.

"#14 can only handle 15*80%=12A on a continuous basis." Correct, but
incomplete and potentially misleading, as it omits the Code definition of a
continuous load: "where the maximum current is expected to continue for 3
hours or more." [Article 100] This is *not* a usual, typical, normal
condition.

Three (3) hours doesn't meet the definition of "continuous" in my world.

The definition of "continuous" in your world, wherever that may be, is
irrelevant. The only meaningful definition, for purposes of determining Code
compliance, is that provided by Article 100 of the NEC: "a load where the
maximum current is expected to continue for 3 hours or more."

And *that* is where the 20% derating applies: to continuous loads as defined
by the NEC. Not as defined by Lew.

Now go take your meds and read your code book again. This time try to
understand what you read.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.