3/3 for 100A


  #1  
Old 01-23-20, 08:13 AM
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3/3 for 100A

I currently have 3/3 nmd 7 for my 100A service. Is this enough? I think I saw it was only rated for 85A?
 
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Old 01-23-20, 08:47 AM
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Are you in Canada? .
 
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Old 01-23-20, 09:32 AM
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In the USA the NEC doesn't allow NM cables to be used as service entrance wiring. This is a question joed should answer since you are in Canada.
 
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Old 01-23-20, 09:50 AM
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NMD7 is an older cable. The ground might be undersized by current codes, but would be grandfathered if currently installed. Non Metalic Dry. It is only allowed in dry locations. The current equivalent would be NMD90 or for USA peeps NM-B.
I don't know the service entrance codes that well but the table for #3 copper says for 60ºC #3 is only good for 85 amps. The 75ºC column says it is good for 100 amps.
 
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Old 01-23-20, 12:25 PM
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This is an old installation so it's grandfathered in anyway. The cable is rated 90 degrees.
The service entrance cable goes to a disconnect and then this nmd wire.
 
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Old 01-23-20, 01:43 PM
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The cable might be rated 90º but are the connection points?
Assuming it was inspected when installed I would just leave as is.
 
  #7  
Old 01-24-20, 03:31 AM
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Isn't nmd7 exactly the same as the current nmd90 - in terms of specs?
 
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Old 01-24-20, 06:05 AM
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Isn't nmd7 exactly the same as the current nmd90 - in terms of specs?
I'm not 100% sure. If it is not exactly the same it is very close.
 
 

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