Possible to use 40A cable with 30A breaker

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Old 07-11-08, 10:01 AM
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Possible to use 40A cable with 30A breaker

I have a stove running off a 40A cable. This cable is going into a 30A breaker. Is this allowed?
My next question is: I want to replace the stove with a laundry machine and/or a dryer. The dryer is supposed to run off 30A. Am I allowed to connect this dryer, which apparently requires 30A, to the 40A cable?
Is this 30A requirement a MINIMUM power requirement or is it not negotiable?
In other words, do I have to replace the 40A cable with 30A, or can I leave it there and run the dryer or the washing machine off it?
 
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Old 07-11-08, 10:58 AM
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Smile

The 40 amp cable would be ok for the dryer, if the dryer was indeed electric 240 v (electric dryers are required to be on 30A independent circuits). The washer of course could not be tied into this circuit. It would have to be on an independent 20 amp circuit. I'm mostly a diagnose and repair kinda electrician, so wait for the pros to verify my response. Have a great day
 

Last edited by sidecutter; 07-11-08 at 11:02 AM. Reason: misspelling
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Old 07-11-08, 11:16 AM
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Don't know why you fooled with the standard font but I almost skipped your post it was so hard to read. .
No such thing as 40 amp cable. #8 cable is often used with a 40 amp circuit. Is that what you mean? It's OK to use #8 0n a 30a circuit. For a dryer you need 3wires plus ground for new installations. Since you are re-purposing this would probably count as a new installation..
 
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Old 07-11-08, 12:05 PM
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Originally Posted by sidecutter View Post
The 40 amp cable would be ok for the dryer, if the dryer was indeed electric 240 v (electric dryers are required to be on 30A independent circuits). The washer of course could not be tied into this circuit. It would have to be on an independent 20 amp circuit. I'm mostly a diagnose and repair kinda electrician, so wait for the pros to verify my response. Have a great day
Thanks. I am now running a separate 20A cable for the washing machine.
 
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Old 07-11-08, 12:24 PM
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Originally Posted by doublezero View Post
I have a stove running off a 40A cable. This cable is going into a 30A breaker. Is this allowed?
Yes, the ampacity of a cable is a maximum rating. You are free to use it at less than the maximum.
 
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Old 07-11-08, 12:38 PM
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Originally Posted by ray2047 View Post
Don't know why you fooled with the standard font but I almost skipped your post it was so hard to read. .
No such thing as 40 amp cable. #8 cable is often used with a 40 amp circuit. Is that what you mean? It's OK to use #8 0n a 30a circuit. For a dryer you need 3wires plus ground for new installations. Since you are re-purposing this would probably count as a new installation..
The cable is 8-3 and it's on a 30A breaker. I've heard it referred to as 40A cable twice today, so that's what I called it.

If you are having trouble reading the Comic font, it must have something to do with your browser settings. It's just about the easiest font to read out there.
 
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Old 07-11-08, 01:48 PM
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If this cable is a true 4 wire you will have to change the range receptale to dryer receptale due the diffrent conferations there

This is a correct one





Merci,Marc
 
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Old 07-12-08, 06:42 AM
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Originally Posted by doublezero View Post
If you are having trouble reading the Comic font, it must have something to do with your browser settings. It's just about the easiest font to read out there.
Not everyone sits hunched over a monitor at a desk to view the Internet. Some of us prefer to set comfortably in our easy chair. Your font is about a third smaller then the usual minimum font size I have set because of its design. Also shaping makes it more difficult to discern.

Sorry guys for the off topic comment.
 
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