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brianmiller
03-16-2012, 06:50 AM
are disribution panels now required to have their own "main breaker"?

I saw two inspection reports this week that called out as defects that the distribution panel downstream of the service equipment panel were required to have their own main breaker for that panel.

b

Jim Port
03-16-2012, 08:16 AM
If the distribution panels were in or on the same building as the service panel the reports are wrong. You can have them as redundant means of disconnect, but they are not required by the NEC.

Derek Guridi
03-16-2012, 10:02 AM
I agree with Jim and will add that a breaker is never required in any panel, although NEC 408.36 does require OCPD protection.

Jerry Peck
03-17-2012, 01:52 PM
are disribution panels now required to have their own "main breaker"?

I saw two inspection reports this week that called out as defects that the distribution panel downstream of the service equipment panel were required to have their own main breaker for that panel.

b

Depends on how you read the question and/or on how those in$pection report stated the problem.

Service entrance conductors are allowed to have the overcurrent protection on the load side of the service entrance conductors because they are "outside the building" (except for the short part "inside the building" closest to the point of entrance of the sersvice entranance conductors into the building).

Feeder conductors, feeding one panel from another panel, are required to have their overcurrent protection on the line side of the feeders, not the load side at the panel they are feeding.

Now, there can be an overcurrent protection at the panel the feeders are serving *in addition to othe overcurrent protection at the panel they tap off from*, this is what Jim was saying is allowed.

Let's take the question a different way, such as the feeders were tapped off feed through lugs from the service equipment ... if the feeder conductors were of sufficient ampacity rating that they matched the rating of the main service disconnect, then no other overcurrent protection is needed. However, if the feeder conductors were small, of less ampacity, then the feeder conductor would need overcurrent protection on the line side of the feeders, i.e., in the service equipment panel where the feeder conductors are tapped off from ... with some exceptions for outside feeder taps (again, though, like the service entrance conductors, those exceptions apply to feeded conductors which are "outside of the building").

If the feeders ares tapped off the service equipment, and there is no overcurrent device at the service equipment, and the feeder conductors are a smaller ampacity than the main service disconnect, and the feeder conductors on inside the building - then that is wrong and you would write it up as the feeder conductors needing overcurrent protection.

All depends on what was actually stated in those reports.

Gunnar Alquist
03-17-2012, 02:22 PM
The way I read brianmiller's question is he is asking if a (sub-like :cool: ) panel needs a disconnect at the (sub-like) panel. As far as I know, the answer would be no. Using the requirements that Jerry mentioned, of course. Having a disconnect at a panel doesn't turn-off the power to that panel, as the feeder conductors are still energized. The only way to completely interrupt power to any remote panel would be at the panel that feeds it (service equipment).

brianmiller
03-17-2012, 03:38 PM
Here is exactly what one inspector said (I have his report):

"There is a main shutoff to the main panel outside the house; however, there is no main shutoff installed in the sub panel inside the house. Today's standards require a main shutoff be installed on all sub panels. "

brian

Robert Meier
03-17-2012, 03:41 PM
Here is exactly what one inspector says (I have his report):

"There is a main shutoff to the main panel outside the house; however, there is no main shutoff installed in the sub panel inside the house. Today's standards require a main shutoff be installed on all sub panels. "

brian

If the panels are in or on the same structure the remote panelboard does not require a main. In a separate structure you would have a different story.

Jim Port
03-17-2012, 05:41 PM
Here is exactly what one inspector said (I have his report):

"There is a main shutoff to the main panel outside the house; however, there is no main shutoff installed in the sub panel inside the house. Today's standards require a main shutoff be installed on all sub panels. "

brian

There is no NEC requirement for this panel to have another main.

brianmiller
03-22-2012, 04:54 AM
I called the two inspectors who said the panel in the house needed a "main breaker" regardless of having the 150amp main breaker outside of the house. They both said that because the panel in the house had more than 6 breakers, it required its own main shut-off breaker......thoughts?

b

Rollie Meyers
03-22-2012, 05:32 AM
I called the two inspectors who said the panel in the house needed a "main breaker" regardless of having the 150amp main breaker outside of the house. They both said that because the panel in the house had more than 6 breakers, it required its own main shut-off breaker......thoughts?

b



They need to cite their source for their opinion, making stuff up does not cut it. Their ignorance can cost people money that is not justified.

Garry Sorrells
03-22-2012, 10:37 AM
Brianmiller,
Did you ask what supported their position ans to site the source?
Did you call an electrician or permit office with the question?
It may be that all three have the same bad information source.
Unknowingly following a misinformed source can cause an exponential growth in an incorrect statement.

By example.
The book that interNACHI hands out has a statement that wood shakes are hand split. When it should say that there are two types of shakes, hand split single sawn and double sawn. Which is how misinformation starts.

Every jurisdiction has it own way of interpretation of codes. Is it possible that yours varies from the basic understood code?

brianmiller
03-22-2012, 03:07 PM
what code do we have to back us up to say that the panel does not require a main breaker?

b

Jerry Peck
03-22-2012, 04:03 PM
what code do we have to back us up to say that the panel does not require a main breaker?

b

The lack of a code requiring it.

It is up to those two inspectors to support their statement, and when they cannot, that is when they will learn that what they said is incorrect ... unless ...

... unless those panels are the service equipment, in which case the maximum allowed number of mains to shut the power off to a structure is 6.

brianmiller
03-24-2012, 07:15 AM
I thought I'd post the pictures....I want to be sure I'm not missing something in this. You see the main disconnect outside the house with a panel inside the home.


Do we still agree the panel inside the house do not require a main disconnect?

b

Jerry Peck
03-24-2012, 07:16 AM
Do we still agree the panel inside the house down not require a main disconnect?

Correct.

Jim Port
03-24-2012, 08:00 AM
Have you asked for a code site to back up the inspectors views? The NEC would not require another main breaker for the inside panel, but a local amendment might.

Robert Meier
03-24-2012, 10:17 AM
I thought I'd post the pictures....I want to be sure I'm not missing something in this. You see the main disconnect outside the house with a panel inside the home.


Do we still agree the panel inside the house down not require a main disconnect?

b

It's not required.

Thom Walker
03-26-2012, 07:04 AM
Whenever a specific statement is challenged, it would benefit all if the Inspector were able to site his source. Even though inspections (in Texas) are no more or less than opinion reports, opinions should be based on supportable standards.

Jimmy Roberts
03-26-2012, 10:14 AM
It appears that NEC 225.40 answers this question.

cuba_pete
03-26-2012, 11:14 AM
It appears that NEC 225.40 answers this question.

Also apply 230.70(A)(1) and you're in business.

The six disconnects does not apply in this situation. That is: "There shall be not more than six sets of disconnects per service grouped in any one location." 230.71, NEC 2011 and as seen here, credit to NECPlus:

NEC 230.71 | Flickr - Photo Sharing! (http://www.flickr.com/photos/57638888@N06/7018324503/)

Robert Meier
03-26-2012, 11:57 AM
I don't see how 225.40 or 230.71 apply to this installation. We're talking about a remote panelboard in the same structure here.

cuba_pete
03-26-2012, 01:51 PM
I don't see how 225.40 or 230.71 apply to this installation. We're talking about a remote panelboard in the same structure here.

Judging by the photos in post #14 it looks like the service disconnect is mounted outside and the main panel is inside. That's why I went with 230.70(A)(1).

Part II of Article 225 covers outside branch circuits and feeders on single managed properties where outside branch circuits and feeders are the source of electrical supply for buildings and structures. 225.40 does not apply to residential services.

There seemed to be a "disconnect" between the OP and what they were being told as to the six breaker rule. I think that was lost in translation somewhere and re-interpreted in relation to 230.71 which, you are correct, does not apply. I only put that in there as a possible link to the weird "requirements" being put forth.

bob smit
03-28-2012, 11:24 AM
Only one possible requirement for an additional disconnecting means for the panelboard inside. The owner/occupant shall have ready access to his/her electrical equipment.
Some inspectors see this as a requirement in the form of a main or no more than six. This being a residential application and the fact it is plainly accessible outside the structure tells me the requirement would not apply here.

Jerry Peck
03-28-2012, 03:49 PM
Only one possible requirement for an additional disconnecting means for the panelboard inside. The owner/occupant shall have ready access to his/her electrical equipment.
Some inspectors see this as a requirement in the form of a main or no more than six. This being a residential application and the fact it is plainly accessible outside the structure tells me the requirement would not apply here.

Those inspectors are correct to some extent in that all occupants shall have ready access to their overcurrent devices, and those overcurrent devices are in the panel. As such, those inspectors are wrong in trying to force a 'panel main' at the panel in each condo when there is no requirement for it.

brianmiller
03-28-2012, 03:59 PM
For my scenerio in the OP, the main shutoff breaker for the house is outside with a distribution panel in the interior (utility room). This panel inside the house is not a service equipment panl. This is what I believe everyone this post is agreeing on?

Also, at least for me, the main breaker outside the house is readily accessible.

bob smit
04-01-2012, 02:55 PM
Like I said J.P., since there seems to be access in the form of a main outside, this requirement for a panel disconnecting means inside would not apply.
Conversely, If the main disconnecting means were in a locked room or another area not accessible to the occupant, a main in the occupants panelboard could serve the function.

I agree that the codes do not state specifics on what/which overcurrent devices require ready access to its occupants.

Garry Blankenship
04-02-2012, 08:58 AM
Whenever a specific statement is challenged, it would benefit all if the Inspector were able to site his source. Even though inspections (in Texas) are no more or less than opinion reports, opinions should be based on supportable standards.

Inspectors are supposed to cite the code section in violation. Every AHJ is or at least can be unique. Regardless; NEC violation or local code violation, it must be supported by the quoted requirement that is in violation. No need for a code, if the inspector can arbitrarily make corrections.

bob smit
04-02-2012, 09:49 AM
I agree Garry. Tis why I carry cheat sheets that I've made up with the code #'s. Having 2 code books (actually 3) up here in MI., I gave up on even trying to remember anymore.

Speaking of which, it's time to start carrying my swim cheat sheets.:rolleyes:
In addition, I always encourage the contractors to challenge anything I write as long as they have a code reference to back up their view.
Even I the all powerful learn something new once in awhile. This also brings the trades to the books that actually govern their work, as opposed to the AHJ being the baa guy. watch out... baa guy coming thru..

Jerry Peck
04-02-2012, 04:41 PM
In addition, I always encourage the contractors to challenge anything I write as long as they have a code reference to back up their view.
Even I the all powerful learn something new once in awhile. This also brings the trades to the books that actually govern their work, ...

I do the same, and I would hope that any inspector worth their salt would do the same.

Yep, it encourages the contractors to look it up, and if they question what I am saying, I will go to the code book (code on computer in my case) and look it up with them - does not take long to find out who is correct ... and the other one learns something new.