James, In the US the NEC is a legal requirement. Local codes must be at=20 least as restrictive as the NEC. Also if the wiring is not done to code=20 and the fire is caused by the poor wiring the insurance does not have to=20 pay. If someone is hurt or killed than the person who did the wiring is=20 now open to criminal and civil charges. I always consider the code as a starting point. As I said before I=20 wire all of the 15 amp 14 gauge circuits to 20 amp 12 gauge specs. I=20 also put in any where from 20 to 100% more circuits depending on the=20 life style of the home owner. In Wisconsin 100 amp panels are required.=20 I always install 200 amp or larger panels. Thanks, rich! On 2/16/2015 6:08 PM, James Cameron wrote: > Agreed. > > I've always considered the critical specification of a circuit breaker > to be the highest current it can hold and not trip, assuming standard > test conditions ... such as voltage, temperature, humidity, magnetic > fields, vibration, gravity, orientation, mounting, atmosphere content, > and atmosphere pressure. > > What some provincial code then says about it, and how it requires any > relabelling or use, is less interesting than the physics. But if the > label is required to be different to that specification, that's > something to watch out for. > > On Mon, Feb 16, 2015 at 06:40:20PM -0500, Allen Mulvey wrote: >> See: >> http://ecmweb.com/basics/sizing-circuit-breaker >> >> "A CB is designed and evaluated to carry 100% of its rated >> current for an indefinite period of time under standard test >> conditions." >> >> The important part is "under standard test conditions." In >> the real world the circuit breaker is likely to heat up >> above "standard" test temperature. The 1996 NEC code >> compensates for this by requiring you to use breakers rated >> at least 20% higher than the anticipated load. >> >> Allen >> --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .