Question, by code, is it legal to tie to the main power lugs on a 200 amp main panel, to run and place a second 200 amp panel beside the existing panel.
Placing the same gauge wire between panels.
OR place a 100 amp breaker and run to the 200 amp panel which will feed
a detached garage with a 100 amp panel.
Question, by code, is it legal to tie to the main power lugs on a 200 amp main panel, to run and place a second 200 amp panel beside the existing panel.
Placing the same gauge wire between panels.
OR place a 100 amp breaker and run to the 200 amp panel which will feed
a detached garage with a 100 amp panel.
I disagree.Remember now to keep track of yer breakers - each downstream breaker should be lower than the one upstream feeding it, and you can't have (should not) more than three breakers to the load. Yeah--I know - someone will tell me that they have four or more and everything has been fine, etc however, overlay your trip curves for the MCCBs and you see what I mean.
No, it's not legal. But you can install a 100 amp breaker to feed a second panel.
I disagree.
Using your guidelines with the above posters scenario, you'd want him to use a 100 amp breaker with 100 amp rated wire feeding a one size smaller 90 amp breaker in the garage panel. Essentially wasting 10 amps for no reason other than keeping the breaker smaller than the one feeding it? He only has 2 breakers before the garage panel, there is absolutely no reason they both can't be rated 100 amps. If one day he should happen to overload it, it'll simply be a race to see which breaker will trip first. Does it really matter which one goes?
No, it's not legal. But you can install a 100 amp breaker to feed a second panel.
I disagree.
Using your guidelines with the above posters scenario, you'd want him to use a 100 amp breaker with 100 amp rated wire feeding a one size smaller 90 amp breaker in the garage panel. Essentially wasting 10 amps for no reason other than keeping the breaker smaller than the one feeding it? He only has 2 breakers before the garage panel, there is absolutely no reason they both can't be rated 100 amps. If one day he should happen to overload it, it'll simply be a race to see which breaker will trip first. Does it really matter which one goes?
Do you think it's okay to add a second 200 amp panel to the line side of a service only sized for 200 amps?Either you have a Code cite or its just your incorrect opinion. Are you saying that the NEC does not allow taps?
"Does it really matter which one goes?"
Sure can matter if someone has to trudge all the way back from one building to another to reset the CB -- its called [bad] practice and/or poor design. You in the habit of putting more than three MCCBs in a string? Tell us how he is wasting 10 amps cuz he downgrades to a 90A in lieu of a 100 at the garage sub panel ....What if he used a 110A or 125A CB at the nippled tapped panel to feed the garage subpanel - does he then gain 10A or 25A
Do you think it's okay to add a second 200 amp panel to the line side of a service only sized for 200 amps?
I'm not going to waste much time replying to this particular quote, I have a feeling I'm simply debating with an armchair electrician who has no real field experience.
Bottom line, this practice is done all the time. There are thousands of installations just like this all over the country. The breaker shouldn't be tripping to begin with if the system was designed properly. You can breaker it down at the garage panel all you want when you do the install. Me? I'm going to give the customer the full 100 amps everytime.