Disconnect Question

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Little Bill

Little Bill

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Do you see any problem with using an AC pull-out, nonfusible disconnect for an outbuilding? I will just be running a single branch circuit. Also, the disconnect would be a 2-pole disconnect and disconnect both the ungrounded and grounded conductors.
 
Little Bill said:
Yep, I know you can you those. However the wire that will be used (already there) will have to be downsized and I thought I could just use the pullout disc. and also use the box as a splice box to downsize the wire.
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The way I read it, if you dont use a snap switch then looks like you are stuck with a disconnect that is suitable for use as service equipment... so my answer is 'no'
 
For a residence I have never seen an a/c disco get turned down. In fact there has been a proposal made by myself and others for the 2014 to change the need for a service rated disco except in certain situations.

But stickboy is technically correct on what the NEC states.
 
Gregg Harris said:
225.31 leads you to 225.36 Suitable for Service Equipment
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I know that exception.

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply
permitted by 225.30 shall consist of not more than six
switches or six circuit breakers mounted in a single enclosure,
in a group of separate enclosures, or in or on a switchboard.
There shall be no more than six disconnects per
supply grouped in any one location.

These are switches so they meet 225.33. Pass inspection.

http://static.schneider-electric.us...Air Conditioning Disconnects/3150BR9801R3.pdf
 
jxofaltrds said:
I know that exception.

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply
permitted by 225.30 shall consist of not more than six
switches or six circuit breakers mounted in a single enclosure,
in a group of separate enclosures, or in or on a switchboard.
There shall be no more than six disconnects per
supply grouped in any one location.

These are switches so they meet 225.33. Pass inspection.

http://static.schneider-electric.us/docs/Advanced Products/Electrical Distribution/Safety Switches/Air Conditioning Disconnects/3150BR9801R3.pdf
Click to expand...

Coffee and jelly and or creme filled donuts for the inspector!:D
 
jxofaltrds said:
I know that exception.

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply
permitted by 225.30 shall consist of not more than six
switches or six circuit breakers mounted in a single enclosure,
in a group of separate enclosures, or in or on a switchboard.
There shall be no more than six disconnects per
supply grouped in any one location.

These are switches so they meet 225.33. Pass inspection.
Click to expand...


I think you are forgetting 225.36
 
stickboy1375 said:
I think you are forgetting 225.36
Click to expand...

Nope just trying to dismiss it.

225.36 Suitable for Service Equipment. The disconnecting
means specified in 225.31 shall be suitable for use as
service equipment.

Service Equipment. The necessary equipment, usually consisting
of a circuit breaker(s) or switch(es) and fuse(s) and
their accessories, connected to the load end of service conductors
to a building or other structure, or an otherwise designated
area, and intended to constitute the main control and cutoff of
the supply.

Service Conductors. The conductors from the service point
to the service disconnecting means.

Service Point. The point of connection between the facilities
of the serving utility and the premises wiring.

Service. The conductors and equipment for delivering electric
energy from the serving utility to the wiring system of
the premises served.

Disconnecting Means. A device, or group of devices, or
other means by which the conductors of a circuit can be
disconnected from their source of supply.

Then other than the exceptions I could never have a disconnect on a residential outbuilding rated less 100 AMPS.

225.39
(C) One-Family Dwelling. For a one-family dwelling, the
feeder disconnecting means shall have a rating of not less
than 100 amperes, 3-wire.

Since I see a conflict I go to 225.38.
 
I know its a crappy requirement that makes no sense, but it says "Suitable for use as Service Equipment". It does not say that disconnect has to BE Service Equipment, just suitable for use as such. Suitable for use as Service Equipment is a common label on many switch and panel board cabinets.

Don't know what they care about a SUSE capability when you have a feeder to a building. You'll never use most of the things that go in to the SUSE requirement. But I don't think you can just dismiss it.

And I think you can have the disconnect rating to be 60A if it is an accessory building and not a full dwelling. Another requirement that seems stupid -- why put in a 60A disconnect if the feeder is only 30A or 40A... But that's the rules.
 
Mike, I really am not following how you are just taking section 225.36 and dismissing it... If you had 6 snap switches, then sure, that could be the disconnect with out being suitable for service equipment on a residential property, but where do you find an AC disconnect being a snap switch?
 
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stickboy1375 said:
Mike, I really am not following how you are just taking section 225.36 and dismissing it... If you had 6 snap switches, then sure, that could be the disconnect with out being suitable for service equipment on a residential property, but where do you find an AC disconnect being a snap switch?
Click to expand...

225.36
Exception: For garages and outbuildings on residential
property, a snap switch or a set of 3-way or 4-way snap
switches shall be permitted as the disconnecting means.

225.38
Exception: For garages and outbuildings on residential
property, snap switches or 3-way or 4-way snap switches shall
be permitted as the disconnecting means.

One limits you to a single disconnect means or a single set. The other allows more. Which applies?

225.33 says I can use 6 switches. 225.36 says those switches must be SUSE. 225.38 (C) says 100 AMPS. Conflict?

I think if something is unclear then I must allow an installation if it is safe and meets the intent of the NEC
 
The OP asked about a pull-out type of AC disconnect. I don't see a pull out type as being a snap switch. The AC disconnects using what looks like a breaker, but is really just a switch, I'd say is a snap switch and you could use that as a building disconnect on residential property only. If that AC disco has a circuit breaker, I'm not sure if that meets the snap switch definition or not. I'd be inclined to say yes.

The wording in 225.36 is slightly inconsistent with the other sections. I think the intent is one snap switch for most installs (either single pole or multi pole). But, you can sometime have multiple circuits to a detached building (such as a 3-way switch circuit), so they are allowing for that. There could be other exceptions where each source has a single snap switch.
 
jxofaltrds said:
225.36
Exception: For garages and outbuildings on residential
property, a snap switch or a set of 3-way or 4-way snap
switches shall be permitted as the disconnecting means.

225.38
Exception: For garages and outbuildings on residential
property, snap switches or 3-way or 4-way snap switches shall
be permitted as the disconnecting means.

One limits you to a single disconnect means or a single set. The other allows more. Which applies?

225.33 says I can use 6 switches. 225.36 says those switches must be SUSE. 225.38 (C) says 100 AMPS. Conflict?

I think if something is unclear then I must allow an installation if it is safe and meets the intent of the NEC
Click to expand...


225.38 C is referencing a dwelling service disconect in wich the minumum service ampacity is 100 amps Same as 220.82A and 230.79C
 
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