#10 wire on a 40 Amp breaker?


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Old 03-14-10, 09:16 PM
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#10 wire on a 40 Amp breaker?

I know the rule of thumb is a 40 amp breaker requires #8 wire, but I'm looking at the installation instructions on a new electric range that I purchased and am wondering if I'm reading them correctly. The serial number plate indicates the KW rating on the range is 12.80. The installation manual for the range has two tables, one for minumum wire size and a second one with power supply cord kit ampere rating information.

The minimum wire size chart indicates that for watts of 8750-14500, minimum wire size for L1 and L2 conductors is 10, for neutral conductor is 12 and for ground conductor is 10.

The second chart indicates that for KW rating of 8.8 to 16.5, minimum cord kit ampere rating is 40 amp.

reason this matters so much to me is this range is replacing an old cook top that is on a 30 amp breaker with #10 wire. I'd like to avoid having new #8 wire pulled to support a 40 amp breaker if I can avoid it.

Thanks for any feedback you give me.
 
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Old 03-14-10, 11:04 PM
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Well wire size aside cook tops are often 240v and ranges are usually 120v/240v. So if you only have two wires and a ground it might not work anyway.

KW rating on the range is 12.80
12800 divided by 240=53.3 anps. While of course you normally wouldn't have all the burners and oven on you can see that 30a on #10 doesn't come close.
 
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Old 03-14-10, 11:14 PM
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Are you replacing from countertop cook top unit to full slide in range ?

If so then no., you can not keep the old 6.0mm≤ {#10AWG } conductors you have to go with 10mm≤ { #8 AWG } minuim size anyway and you have to run 4 conductor cable { Black , Red , White et green or bare conductors } that will useally stamp 8-3 NM and that is the only way you can use the 40 amp breakers in there.

Merci,Marc
 
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Old 03-15-10, 08:29 AM
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Hey Marc, thanks. I am replacing a cooktop with a slide-in range.
 
 

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