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Kyle_in_rure
Jan 19, 2013, 10:30 PM
Hello,
A friend of mine has what I would describe as "325 amp service" in his home: a 200 amp panel and a 125 amp panel, both fed directly from the meter. Although the 200 amp has a main breaker, the smaller panel doesn't have a main, so the only way to shut off the power to this panel is to pull the meter. I was always under the impression that any panel besides subpanels had to have a main breaker, but I am no electrician. Any ideas/codes that address this? What protects the wires feeding this panel?

tkrussell
Jan 20, 2013, 06:32 AM
Nothing is protecting this feeder or panel. Somehow, a serious fire hazard has been allowed to exist by not having any short circuit or overload protection for this smaller panel.

This condition cannot be allowed to remain.

And it is a 320 amp service, based on 80% of 400 amp, not 325 by simply adding the ratings of breakers. If your not an electrician, stop making assumptions.

Kyle_in_rure
Jan 20, 2013, 07:36 AM
Well, now I know. How would this have passed inspection? I've seen another setup exactly like this before in a different house. Is a main just not added because the small 125 amp panels are frequently used as subpanels?

donf
Jan 20, 2013, 09:25 AM
Kyle,

Even sub panels need to be protected, either by a "Main Cut Off Switch" ether at the sub panel or meter or at the panel itself or a main breaker. Also. You could use the six switch to kill the branch circuits in the sub panel.

Kyle_in_rure
Jan 20, 2013, 10:48 AM
I understand that sub panels still need to be protected; I meant that since they are protected by a breaker in the main panel they often don't have a main breaker directly in the actual sub panel.

donf
Jan 20, 2013, 11:38 AM
Kyle,

You are describing a situation where the connection to second service is coming directly off a meter feed. Making this a main service panel board, not a sub panel. A sub panel is fed from a panel board, not a meter.

Check for a main disconnect at meter or near the panel board. If there is none, then a main disconnect switch should be installed in front of the "Service Rated" panel board, a main circuit breaker or a MLO breaker panel with up to a six switch positions to kill the panel board.

Personally, I would use a main disconnect in front of the panel board. I would want to kill everything to the panel board at once.

Kyle_in_rure
Jan 20, 2013, 01:58 PM
Thank you for the answers.

tkrussell
Jan 21, 2013, 07:09 AM
Stop discussing "subpanels" and panels. The word "subpanel" is written only once in the entire NEC 2008 editon, and it is industrial section, and does not apply to this.


Whether a Main Breaker at the meter is needed depends on where the panel is located and how much feeder cable is inside a structure.

Since the 200 Amp feeder has a breaker at the meter, it would be safe to assume the 125 amp panel requires a breaker at the meter.


Code states that service disconnecting means , if inside, be at the "nearest the point of entrance of the sevice conductors." This means the Main Breaker must be very close, the service feeder cannot go indefinitely.

If , for example, this 125 amp panel is mounted inside but on an exterior wall, this panel may have a Main Breaker inside the panel, and one would not be required at the meter.

All depends on the location of the panel will dictate where the Main Breaker is to be located.

Kyle_in_rure
Jan 21, 2013, 02:43 PM
So, bottom line, the smaller panel still needs a main shutoff, because there is no other disconnect besides the meter itself.

I guess I'm trying to figure out why it would have been installed this way in the firstplace; the house is only a few years old and codes/inspectors are strict in the area. Guess it was an oversight.