Panel board capacity

[Ron Waller]

Does a 200 amp main panel ever have more than 100 amps in each leg of a balanced feed?

[Robert J. OConnor]

How about 105A on each leg which should not trip the main

[Roy D. Cooke, Sr]

Originally Posted by Ron Waller

Does a 200 amp main panel ever have more than 100 amps in each leg of a balanced feed?

Yes could have over 200 amps per leg for a short period .
Constant load I think 160 amps . been out of the trade too many years but I think it is 80% . I expect some one might add to this thanks .. Roy

[KEVIN WOOD]

Robert your response does not even make sense!

How about 105A on each leg which main not trip the main

[KEVIN WOOD]

I am not an electrician but I remember 75% but I am not sure. I hope that someone can clarify this, it would be nice to know if it has changed.
Roy I think you meant to say over 100/leg.

[Roy D. Cooke, Sr]

Originally Posted by kwood

I am not an electrician but I remember 75% but I am not sure. I hope that someone can clarify this, it would be nice to know if it has changed.
Roy I think you meant to say over 100/leg.

He said 200 amp panel and they are 200 Amps on each leg of a 200 amp panel


( " Panel board capacity
Does a 200 amp main panel ever have more than 100 amps in each leg of a balanced feed? ")

[KEVIN WOOD]

OK we went from 100/leg to 200/leg so your last comment says 160 constant load. So I need more clarification if you can Roy.

[Roy D. Cooke, Sr]

Originally Posted by kwood

OK we went from 100/leg to 200/leg so your last comment says 160 constant load. So I need more clarification if you can Roy.

The question was (" Panel board capacity
Does a 200 amp main panel ever have more than 100 amps in each leg of a balanced feed? ")

And the answer a 200 amp panel is 200 amps on each leg the Constant load is 80% , I was wrong at 70% .
You can over load a breaker for a short period like motor starting so yes it can exceed 200 amps per leg but a breaker should eventually dump at over 80% of rated load .

[Robert Meier]

At 240 volts a 200 amp panel will have a capacity of 200 amps of load. At 120 volts the same panel will have a capacity of 400 amps. A full 200 amp, 240 volt load might take a long time to trip the 200 amp OCPD if at all. A continuous load is one that will continue for 3 hours or more at maximum ampacity. Continuously loaded circuits and feeders must be sized at 125% of the connected load.

[KEVIN WOOD]

Thanks Robert M and Roy. I think that has now been cleared up.
Sized at 125% for motors
80% over rated 200 Amps/leg and it will trip the main.

[Robert Meier]

Originally Posted by kwood

80% over rated 200 Amps/leg and it will trip the main.

Not sure what you mean by this? Are you saying >160 amps will trip the 200 amp OCPD?

[KEVIN WOOD]

I made no comment about 160 amps that is Roys.

[Robert J. OConnor]

He asked if there can be more than 100A per leg, and the simple answer is yes. An example is 105A per leg. Each leg of a typical 200A 120/240V panel should have a 200A capacity.

Circuits and feeders should only be loaded to about 80% of the rating (wire sized for 125% of the load), but that load would likely never trip a breaker. Loads need to be in the range of about 100% to 130% of breaker rating to trip a breaker.

[KEVIN WOOD]

Unless of course if you are dealing with Federal Pacific but that is a whole new topic. LOL

[Roy D. Cooke, Sr]

Originally Posted by kwood

Unless of course if you are dealing with Federal Pacific but that is a whole new topic. LOL

I see nothing wrong with the Canadian FP panels .

Do you have any evidence to show that I am wrong .

I do have a FP in my home and see these in many homes .

They are still being installed in Canada. Thanks ... Roy