Temporary Constructions

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Inspectorcliff

Senior Member
Location
Colorado
longtime no ask? Hope your all fine. My question to the wizards of the THHN/SOW ha, is Do we require a Main Disconnect in a panel, such as a QO 8-16 below a meter, with two 15 amp overcurrent devices that feed two individual receptacle outlets? Thanks and references please. I personally do not think so as of the 2008 code. :grin:
 

pete m.

Senior Member
Location
Ohio
It may also depend on the listing for the panelboard. If the panelboard requires that a main be installed to render it suitable for use as service equipment then the answer to your question is yes.

Pete
 
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Inspectorcliff

Senior Member
Location
Colorado
Guys

Guys

I agree, no main required if the panel is suitable and does not require it as part of the listing and there are 6 or less movements of the hand.

Thanks.;)
 

cripple

Senior Member
Temporary Constructions

Article 590.2(B) States that except as specifically modified in this article, all other requirements of this Code for permanent wiring shall apply to temporary wiring installations. Since 590 do not modify 230 you would have to follow the installation requirement for services. 230.90(A) permits six or less overcurrent protection devices without a main.
 

Inspectorcliff

Senior Member
Location
Colorado
Article 590.2(B) States that except as specifically modified in this article, all other requirements of this Code for permanent wiring shall apply to temporary wiring installations. Since 590 do not modify 230 you would have to follow the installation requirement for services. 230.90(A) permits six or less overcurrent protection devices without a main.
Excellent identifier there Cripple. I appreciate all of the input I get from the forum. Makes me proud to be an associate (student of life)!:grin:
 

Volta

Senior Member
Location
Columbus, Ohio
longtime no ask? Hope your all fine. My question to the wizards of the THHN/SOW ha, is Do we require a Main Disconnect in a panel, such as a QO 8-16 below a meter, with two 15 amp overcurrent devices that feed two individual receptacle outlets? Thanks and references please. I personally do not think so as of the 2008 code. :grin:
As others have said, probably ok, but you need to read the full set of instructions. It is easy to stop after "when not more than six breakers are installed" and miss the part that says "unless used as an appliance and branch-circuit panelboard".
Maybe I'm off base here, but if this is a temporary, doesn't 590.4(E) come into play?
Temporary services need to comply with the whole of Article 230.
 

hurk27

Senior Member
As others have said, probably ok, but you need to read the full set of instructions. It is easy to stop after "when not more than six breakers are installed" and miss the part that says "unless used as an appliance and branch-circuit panelboard".

Temporary services need to comply with the whole of Article 230.

and 408.16 more then 10% of the circuits are for branch circuits 30 amps or less right?
or did this change in the 2008?
 

hurk27

Senior Member
and 408.16 more then 10% of the circuits are for branch circuits 30 amps or less right?
or did this change in the 2008?

OK I guess 2008 did some rearranging, seems 408.36 exception 1 might allow it, but it seems to me this is talking about main breakers for feeders, not branch circuits, so 408.36 seems it would require a panel board with just 2 20 amp breakers supplying branch circuits to be protected by OCPD.
 

hurk27

Senior Member
in thinking about 110.26, it would seem to have some kind of means to shut down power to a branch circuit panel board since at some time breakers will be changed and or added to, thus leaving the busses hot would incite much more danger? a service panel board just feeding 2/3-pole breakers which act as mains to other panels would not require as much work in it?
 

Volta

Senior Member
Location
Columbus, Ohio
OK I guess 2008 did some rearranging, seems 408.36 exception 1 might allow it, but it seems to me this is talking about main breakers for feeders, not branch circuits, so 408.36 seems it would require a panel board with just 2 20 amp breakers supplying branch circuits to be protected by OCPD.

Maybe. My original thought was from a recent panelboard label.

On this first reading of 408.36 Exc.#1 I assumed it was the old parallel main set-up they were referring to, but now I think that the two sentances are completely independant. The first allows main lugs, the second limits split busses.

The main lug allowance in my recent project was further limited by the specific instructions allowing up to six disconnects when not used as a lighting and appliance panelboard.

And you're right, lighting and appliance (408.34) is not code anymore, but my panel was listed before this edition, so ... I think it would still be enforceable, maybe :roll:.
 

Volta

Senior Member
Location
Columbus, Ohio
in thinking about 110.26, it would seem to have some kind of means to shut down power to a branch circuit panel board since at some time breakers will be changed and or added to, thus leaving the busses hot would incite much more danger? a service panel board just feeding 2/3-pole breakers which act as mains to other panels would not require as much work in it?

Except that 110.26 is about working hot, not deenergized. Now 70-E might push things toward main breakers, but there is no point at which it is safe for everybody. Somebody upstream has to shut it down once in a while.
 

hurk27

Senior Member
It has always seemed that when you had line to neutral loads that exceeded 10% we always had to have a main, now I'm not so sure anymore, and cant remember the answers to the questions at the IAEI sectionals meetings:confused:
 

cripple

Senior Member
As others have said, probably ok, but you need to read the full set of instructions. It is easy to stop after "when not more than six breakers are installed" and miss the part that says "unless used as an appliance and branch-circuit panelboard".

The maximum six set disconnects per service requirement is found in 230.71(A) and I do not find anything about ?unless used as an appliance and branch-circuit panelboard". Could you state the section you are quoting, I would like to know my thinking has gone be the way side.

"230.71 Maximum Number of Disconnects.
(A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be not more than six sets of disconnects per service grouped in any one location."
 

Volta

Senior Member
Location
Columbus, Ohio
The maximum six set disconnects per service requirement is found in 230.71(A) and I do not find anything about ?unless used as an appliance and branch-circuit panelboard". Could you state the section you are quoting, I would like to know my thinking has gone be the way side...

Your thinking is fine, as far as I know :grin:! The text I was referring to was written on the Cutler-Hammer BR Series Main Lug panel. Listed before the 2008 edition, but installed this month. Gently aged :roll: :cool:.
 
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