out building disconnect

[kwired]

This is somewhat the situation that has come up in other threads recently where there has been disagreement of what is a separate building or structure.

In this case most would say these cabins were separate buildings, if they are the rules are pretty clear.

What if they were just posts with a single receptacle mounted on them?

If they are separate structures they require a disconnect rated for service equipment, and a grounding electrode.

If they are on same property as a dwelling they still require a disconnect but a simple snap switch is acceptable.

I see posts with receptacles mounted on them all the time with no disconnect. Are they all wrong?

 

[iwire]

That is part of why I suggested in post 4 to run a feeder that hits every building and tap to a breaker on each building.

You need a service rated disconnect at every building no matter what.

You need a grounding electrode at every building no matter what.

How does not having overcurrent device not require a grounding electrode? I see nothing in 250 part III that would permit this. 250.50 says you need it.

The exception says no GES needed for a single branch circuit.

I agree your suggestion of one long feeder might make sense, tough to say without a lay out.

If the electrical supply is in the middle or end of a straight line of cabins it could work out well, if the cabins are scattered that might cost more to run one feeder. Definitely worth considering both and pricing them to see which comes out cheaper.

 

[iwire]

This is somewhat the situation that has come up in other threads recently where there has been disagreement of what is a separate building or structure.

In this case most would say these cabins were separate buildings, if they are the rules are pretty clear.

What if they were just posts with a single receptacle mounted on them?................

I see posts with receptacles mounted on them all the time with no disconnect. Are they all wrong?

Per the wording of the NEC the posts are separate structures ......... but no ....... I can't say I have treated them as such.

A job I did at a fair ground comes to mind, I installed four 208 volt 30 amp and one 120 volt 20 amp circuit on a 10" X 10" wooden post. It looks good and passed inspection but looking back on it ......... too many branch circuits to a structure .... no GES and no disconnecting means.

 

[Dennis Alwon]

So, 225.36

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

However, 225.33 (B) states that

(B) Single-Pole Units. Two or three single-pole switches or breakers capable of individual operation shall be permitted on multiwire circuits, one pole for each ungrounded conductor, as one multipole disconnect, provided they are equipped with identified handle ties or a master handle to disconnect all ungrounded conductors with no more than six operations of the hand.

Where does it state that these switches must be service rated. Art. 225.36 Suitable for service equipment refers back to 225.31. It seems there is a circular motion going on here that gets us nowhere. I have never seen a sp switch that was service rated so why does 225.33(B) mention it.

I would have no issue using a dp switch in this situation. A summer cabin is not much different than an outbuilding on residential property. It seems at most unclear and I would have no issue but I would ask the ahj involved.

 

[kwired]

Ok 250.32 (A) exception does not require a grounding electrode if supplied by an individual branch circuit. Does nothing to change the disconnect requirements though. If residential property must at least have a snap switch.

 

[iwire]

Where does it state that these switches must be service rated.

IMO 225.36 is clear even if it does not make sense.

225.36 gives us an exception and .33(B) tells us we can use SP units. It also includes breakers which would be service rated in the proper enclosure.

I would have no issue using a dp switch in this situation.

What you would do has no bearing on what the code requires and should not have a bearing on what we advise here IMPO.

The OP is quite capable of ignoring the code on his own.

 

[cplinc35]

There is over current protection, at the meter.

 

[Dennis Alwon]

Obviously I don't think it is clear and there is nothing wrong with telling the OP to check with the ahj. They do have the ability to give a waiver. My comment as seeing no issue with it did not state to just do it. I said I would have no issue....

 

[iwire]

Obviously I don't think it is clear

I think you may be trying to make it be what you think it should be and not applying Charlies rule.

225.36 is short and only has one exception.

there is nothing wrong with telling the OP to check with the ahj.

I agree 100%

They do have the ability to give a waiver.

I have never seen an AHJ actually give 'special permission' as 90.4 would require and that means the EC is on the hook for a violation forever. Maybe it happens other places but not around here.

Special Permission. The written consent of the authority
having jurisdiction.

 

[kwired]

IMO 225.36 is clear even if it does not make sense.

There is the quote of the day

Actually it does not make any sense in the other thread about supply conductors from generators.

Here it is very clear.

 

[cowboyjwc]

I didn't read all of the posts, but you'll need a ground rod at each building too.

 

[kwired]

I didn't read all of the posts, but you'll need a ground rod at each building too.

It was suggested if the disconnect at each building did not contain an overcurrent device you don't need a grounding electrode, I disagree with that.

 

[Dennis Alwon]

I didn't read all of the posts, but you'll need a ground rod at each building too.

The OP may only have a MWBC going to the buildings.

 

[cplinc35]

Hot,neutral,ground #12 thhn on an arc fault 20 amp breaker to a nema 3r disconnect on the cabin and I need a ground rod? I vaguely remember something about everything going back to its place of origin which is the meter socket/panel. Its been a while but you guys have been a great help and have me digging through my code book. I just wish they wrote it in english!

 

[kwired]

The OP may only have a MWBC going to the buildings.

If it is fed with a single MWBC that allows the disconnecting means to not be service rated - but only for accessory buildings at dwelling locations, I can't find anything that omits the requirement for installing a grounding electrode even in the buildings at dwelling locations. It either is not there or I am not looking hard enough. please give us code section if you find it.

 

[Dennis Alwon]

If it is fed with a single MWBC that allows the disconnecting means to not be service rated - but only for accessory buildings at dwelling locations, I can't find anything that omits the requirement for installing a grounding electrode even in the buildings at dwelling locations. It either is not there or I am not looking hard enough. please give us code section if you find it.

I already stated my opinion but I was responding to cowboy by stating a ground rod is not necessary if it is a mwbc. Do you disagree with this?

 

[iwire]

Here it is very clear.

I agree, but I still don't think it really makes sense.

 

[iwire]

It was suggested if the disconnect at each building did not contain an overcurrent device you don't need a grounding electrode, I disagree with that.

But it is true.

If it is a feeder a GES is required.

If it is single branch circuit a GES is not required.

The addition of an OCPD at the building makes it a feeder.

 

[iwire]

If it is fed with a single MWBC that allows the disconnecting means to not be service rated - but only for accessory buildings at dwelling locations, I can't find anything that omits the requirement for installing a grounding electrode even in the buildings at dwelling locations. It either is not there or I am not looking hard enough. please give us code section if you find it.

The exception

250.32 Buildings or Structures Supplied by a Feeder(s)
or Branch Circuit(s).

(A) Grounding Electrode. Building(s) or structure(s) supplied
by feeder(s) or branch circuit(s) shall have a grounding
electrode or grounding electrode system installed in
accordance with Part III of Article 250. The grounding
electrode conductor(s) shall be connected in accordance
with 250.32(B) or (C). Where there is no existing grounding
electrode, the grounding electrode(s) required in 250.50
shall be installed.


Exception: A grounding electrode shall not be required
where only a single branch circuit, including a multiwire
branch circuit, supplies the building or structure and the
branch circuit includes an equipment grounding conductor
for grounding the normally non?current-carrying metal
parts of equipment.

 

[kwired]

I kind of thought there was an exception for building fed by branch circuit but was not finding it. Thank you.