Amperage

kurmudgeonDecember 6, 2009

I'm wiring up some baseboard heaters using 12 ga cable. I have been told that 12 ga cable won't safely take

more than 16 Amps....

I have also been told that 12 ga cable on a 25 amp breaker

is fine for 4800 watt baseboard heaters....20 amps

Which is correct.

Thank you

Thank you for reporting this comment. Undo
hexus

#12 AWG can only be used with a maximum circuit breaker of 20 amps. Whoever told you 25 is WRONG.
As for the 16 amps. 16 is 80% of 20. You can only load a circuit to a maximum of 80% of the over current protection rating.

if you have a 4800 watt heater using 240 volts that comes to 20 amps. you HAVE to pull #10 AWG to it and use a 30 amp breaker.

    Bookmark   December 6, 2009 at 8:19PM
Thank you for reporting this comment. Undo
kurmudgeon

hexus..our code (Canada) says they have changed the rules allowing higher rated breakers to make greater loading possible. Allowing a 25 amp breaker for 4800 watts.
Why they allow this I don't know.

Would you suggest I ignore the code, if I use 12 ga cable, and go with 20 amp breakers loading only to 16 amps?

    Bookmark   December 6, 2009 at 8:34PM
Thank you for reporting this comment. Undo
petey_racer

Just some clarification:

"#12 AWG can only be used with a maximum circuit breaker of 20 amps. Whoever told you 25 is WRONG."

There ARE some instances where #12 can be on a 25A breaker, but they do not apply here.

"As for the 16 amps. 16 is 80% of 20. You can only load a circuit to a maximum of 80% of the over current protection rating."

This is not true in most instances. You certainly CAN load a circuit to 100%.
Continuous loads though, or those considered continuous loads such as electric heat, DO have to be kept to 80%.

That said, I am not familiar with the Canadian code on this so I won't comment further on that.

    Bookmark   December 6, 2009 at 8:46PM
Thank you for reporting this comment. Undo
hexus

I have no clue on Canadian codes. My mistake I assumed you were in the states.

    Bookmark   December 6, 2009 at 8:47PM
Thank you for reporting this comment. Undo
kurmudgeon

I don't know why they changed the code..which used to be the same as yours in this case but I think i'm going to go with your advice...
Our code seems a little too liberal for me.
Thanks for the responses...appreciated

    Bookmark   December 6, 2009 at 9:00PM
Sign Up to comment
More Discussions
Goodbye Phone Jack: what to do with wires?
We want to remove this phone jack. It's in a useless...
maggiepatty
Power to shed
Looking to run one 20 amp circuit to my shed and I'm...
ohio45424
Outdoor subpanel as AC disconnect
Can we use an outdoor subpanel as an AC disconnect?...
ylmzm
Humming Transformer
Last summer the POCO replaced the transformer on the...
mike_kaiser_gw
Need to Understand GFCI Requirements.
I posted this in the remodeling section, but I think...
homechef59
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™