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REH777
Sep 15, 2007, 11:08 AM
I currently have a kiln that is listed as 30 Amp on the kiln info plate. My new kiln is listed as 44.2 amps on the info plate. The Wire is 8 AWG and the Kiln is less than 10 feet from my 200 AMP service panel. I know that I need to change the Receptacle. I currently have a
14-50P and the new kiln has a 14-60P.
(I used the following site for the Receptacle information) Quail Electronics (http://www.quail.com/nema.cfm)
My question is what breaker do I need and do I need to change the wire from 8 AWG to 6 AWG? My current breaker is a double pole 30 amp, will that work?

tkrussell
Sep 15, 2007, 02:27 PM
Is the #8 wire in NM-B Romex? Or what kind of wire or cable do you have?

Romex #8 can only have a 40 amp breaker, MC cable or pulled wires with THHN insulation can have a 50 amp breaker.

The breaker needs to be 25 % larger than the 44 amp load, so 55 amps, or the next size up standard breaker, which is 60 amps.

Therefore, you need to use a min of #6 wire THHN. Romex still not allowed, only good for 55 amps.

REH777
Sep 15, 2007, 03:02 PM
Thanks for your answer.
The wire is pulled wires in metal conduit. They have the following printed on them
"Type MTW or THWN or gasoline & oil resistant II or AWM 600 volts".
When you say 60 amps standard breaker is that double pole 30 Amp (30+30=60) or
Double pole 60 amp breaker.

tkrussell
Sep 15, 2007, 05:58 PM
A double (2) pole 60 amp CB, with #6 THHN wire pulled through the conduit.

REH777
Sep 16, 2007, 02:24 PM
Thanks for your help!