Want 14 wire with a fixed load on 20A breaker HELP! 1

[HighPotential]

Has anyone gotten the permitting authority to buy-off on using 14 wire for the siwtched legs of fixed lighting loads when the system uses No.12 wire and 20A breakers everywhere else? NEC rates 14 at 25A but limits the overcurrent device to 15A. I was thinking that since 14 is rated for 25A and the fixed loads don't exceed 600VA that I might beable to convince them. 14 is a lot easier to work with than 12 in solid.

Thanks!

 

[advidana]

Used 12 gage copper for 20 amps. Save youself a lot of construction defect law suites. That kind of thinking raising everybodies construction insurance.

 

[HighPotential]

LOL!

 

[jOmega]

Which wire will produce more heat under a fault condition..shorted fixture, grounded fixture, etc.. ?

And with more heat.. what happens to the insulation ?

If the circuit protector is thermal as opposed to magnetic, then there is a finite time that must elapse before it trips... which allows heat buildup in the wire... and..... fire maybe ?

So which wire would you like in your residence on a 20A circuit..... 14...or 12 ..... ?

 

[busbar]

There's an old saying: "Don't fight city hall."

 

[dpc]

The circuit protection requirements for #14 and #12 have a long and venerable history in the NEC. I know of no instances where any exception has ever been made.

When dealing with codes and standards, it is generally better to accept what is there rather than trying to apply logic or common sense. Neither will get you very far.

So maybe if the load is small enought, you could use #16 wire.

If this is somewhere you are going to live or work, do yourself a big favor and use #12. You'll have less problem with flicker, voltage drop, tripped breakers, etc.

Ask any electrician what he would use in his own house.

Just my $0.02.

 

[freddycor]

HighPotential:

Maybe making a " fear analisys ", you will have your own answer.
Saludos.

Alfredo Corona
Mexico

 

[peebee]

#14 for 15 amps and #12 for 20 amps is standard practice in even the goofiest rural residential installations.

If the fixed loads don't exceed 600va, and you find #12 too hard to work with, well, then swap out the breaker for a 15 amp breaker. Problem solved.

Re: "The circuit protection requirements for #14 and #12 have a long and venerable history in the NEC." -- from the 1899 1st Edition NEC:

The ampacity of #14 is given as 12 amps (rubber covered indoor installations) or 16 amps (weatherproof wires);
and #12 is given as 17 or 23 amps. Even in 1899 they wouldn't let you run 20 amps on a #14. (see mikeholt.com for a pdf file of the 1899 NEC).