Feeder ampacity

[infinity]

This is not a tap. The #4/0 are protected at 250 amps, the next standard size up from their ampacity of 230 amps. They feed a 225 amp panel with a 225 amp main, all is good.

 

[iwire]

...and the 225A CBer in the panel is being supplied by a 250A CBer...this is not permitted.

Of course we can supply a 225 amp breaker with a 250 amp feeder.

 

[iwire]

This is not a tap. The #4/0 are protected at 250 amps, the next standard size up from their ampacity of 230 amps. They feed a 225 amp panel with a 225 amp main, all is good.

I agree, as long as there is a 225 amp main breaker at the panel all is good.

 

[infinity]

I agree, as long as there is a 225 amp main breaker at the panel all is good.

I think that we're good:

The service has a 400 Amp main with (3) 250A feeder breakers each supplying 4/0 feeders. Each feeder lands on a 225Amp main on a sub-panel.

 

[Smart $]

Of course we can supply a 225 amp breaker with a 250 amp feeder.

...230A feeder to be more precise (assuming no ambient or derating adjustment).

408.36 Overcurrent Protection. In addition to the requirement of 408.30, a panelboard shall be protected by an overcurrent protective device having a rating no greater than that of the panelboard. This overcurrent protective device shall be located within or at any point on the supply side of the panelboard.

This takes us back to your first post to this thread...

 

[Dennis Alwon]

So are we all Happy. I am.. I agree that the install is Okay.

 

[iwire]

...230A feeder to be more precise.

OK Mom.


Of course we can supply a 225 amp breaker with a 250 amp breaker.

 

[Twoskinsoneman]

So are we all Happy. I am.. I agree that the install is Okay.

Maybe Pierre is just ornery today? Feel sorry for anyone who got inspected by him today....

 

[iwire]

Feel sorry for anyone who got inspected by him today....

They all got red tagged.

 

[Pierre C Belarge]

Actually I am in a good mood you punks...:grin:

They get red tagged whether or not I am in a good mood.

 

[iwire]

Actually I am in a good mood you punks...:grin:

They get red tagged whether or not I am in a good mood.

I thought the red tags where what puts you in a good mood.














(I know that is not true )

 

[augie47]

Pierre, Have you been convinced that the original post meets Code ?

 

[Pierre C Belarge]

I agree with the others if the panel has a 225 main in it.

If the panel is main lug only there is a violation of 408.36

I just read 408.36 again, maybe a little more scrutinizing than in the past.

I was more focused on this train of thought, then the OP's installation.

I guess it is never too late to learn something new...


Darn...now I am going to have to go and take all the red tags back from today. Maybe not.:grin:

 

[Pierre C Belarge]

I thought the red tags where what puts you in a good mood.














(I know that is not true )

You know, I will go home and cry, wait, I am at home.:grin:

 

[M. D.]

I just read 408.36 again, maybe a little more scrutinizing than in the past.

Well,.. at least you now have a better understanding of what they may have been saying as you walked away:roll: