"Morgans" writes:

"Mike Marlow" wrote

Cannot understand why you would say that. Odds are it is 12 ga.

Why? Code only calls for 15 amp, 14 ga. in bedrooms.


You are mistaken. The code requires a certain density of
receptacles in a bedroom. The ampacity of the branch circuit is
calculated based on the number of receptacles on a branch circuit and some
very conservatively (err on the side of safety) estimated expected loads.

The gauge of the branch circuit wiring is based on the rating of the overcurrent
protection device with the required branch circuit ampacity. An
overcurrent protection device rated at 20 amperes, will require a mininum
of AWG 12 wire (possibly AWG 10 depending on the distance between the
overcurrent protection device and the set of protected devices to avoid excessive
voltage drop).

The typical residential duplex NEMA 5-15R receptacle is rated to support two devices
which combined, must not consume more than 1.8KW. These receptacles
will accomodate only NEMA 5-15P plugs. NEMA 5-20R duplex receptacles
are available that will accomodate both 5-15P and 5-12P plug, but are very
uncommon in residential work.

Note again, the branch circuit wiring is always sized to the overcurrent
protection device, not the branch device, so a 20A breaker protecting four
or five NEMA-15R duplex receptacles would require miniumum AWG12 wiring
throughout the branch circuit.

scott