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Old 08-14-2012, 09:33 PM   #61
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romEx, not romAx.

That is all.

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Old 08-14-2012, 09:35 PM   #62
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Originally Posted by stickboy1375 View Post
I've been saying this the entire time.. Finally you got it... Did you not read that the motor contains the over current protection?
Overload?
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Old 08-14-2012, 09:39 PM   #63
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Overload?
After a few beers they all seem the same.
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Old 08-14-2012, 09:40 PM   #64
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I am curious to know if the disco will be fused or non-fused.
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Old 08-14-2012, 09:41 PM   #65
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I am curious to know if the disco will be fused or non-fused.
I doubt it needs to be fused, I have yet to come across a unit that requires fuses...
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Old 08-14-2012, 10:21 PM   #66
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are you saying you are not required to size the wire based on the breaker?

The breaker size is exactly how I size the wire. I size the breaker to the unit and run the wire that will carry the amps of the breaker.
You do not need to size the wire to the breaker ampacity for an A/C unit. The breaker and wiring are sized from the nameplate data. The wiring is sized for the running load. The breaker is sized for the startup. To run 50 amp wiring because the unit requires a 50 amp breaker for startup is a waste and completely unnecessary.
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Old 08-14-2012, 10:22 PM   #67
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You do not need to size the wire to the breaker ampacity for an A/C unit. The breaker and wiring are sized from the nameplate data. The wiring is sized for the running load. The breaker is sized for the startup. To run 50 amp wiring because the unit requires a 50 amp breaker for startup is a waste and completely unnecessary.
I think this was mentioned and forgotten...
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Old 08-14-2012, 10:24 PM   #68
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Originally Posted by Jim Port View Post
You do not need to size the wire to the breaker ampacity for an A/C unit. The breaker and wiring are sized from the nameplate data. The wiring is sized for the running load. The breaker is sized for the startup. To run 50 amp wiring because the unit requires a 50 amp breaker for startup is a waste and completely unnecessary.
And it's what someone who does not know the code would do.
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Old 08-14-2012, 10:37 PM   #69
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I don't think anyone said conduit would be cheaper. The comment was made that should a conduit system be used you could take advantage of the higher ampacities afforded to THWN due to the higher temperature column and run the #10s.

You could run the 8-2 NM inside and switch to #10 THWN at the disco to the unit and be compliant.

I also don't know why you would be so scared to ask an inspector for an citation of the violation he thinks you commited. They are required to cite the violation. If they can't show you it should pass and the inspector should learn from this. If they are correct you should learn something and both move on.

BTW, it is Romex, a trademarked brand name, not romax.
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Old 08-14-2012, 10:41 PM   #70
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I totally dislike when a simple thread has to go to beyond 50 posts when the correct answer was given in post 3, a new thread should have been started and resolved the unawareness of the actual code vs what I think it should be scenario... This just screws up the OP and scares them away.

Last edited by stickboy1375; 08-14-2012 at 10:44 PM.
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Old 08-15-2012, 07:22 AM   #71
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FWIW I appreciated the discussion and education. I doubt I will ever be wiring a unit but it's nice to have a better understanding of how the breaker size, wire size, and MCA data are related.
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Old 08-15-2012, 04:13 PM   #72
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FWIW I appreciated the discussion and education. I doubt I will ever be wiring a unit but it's nice to have a better understanding of how the breaker size, wire size, and MCA data are related.
Here is the real breakdown, the manufacture does all the math required by article 440 of the NEC, they will take the largest motor and add 125% to this number then add all the other motors, this number becomes the MCA, Minimum circuit ampacity, Now, since we are dealing with motors, and they contain there own internal thermal protection, (circuit breaker) we can add up to 225% to the MCA to come up with a maximum circuit breaker, since this breaker is only supplying ground-fault and short-circuit protection...


Its pretty easy to grasp with a little knowledge, but this topic just leaves so many people in disbelief, because of the fact you have a larger breaker size than wire size...
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Old 08-15-2012, 11:12 PM   #73
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I feel the questions from the OP have been well answered by now. Posts have been removed for breaking the forum rule; treat other members with respect found at the bottom of every page under "Privacy statement" or "Terms of service". Thread closed. Gary

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