branch circuits for a greenhouse?

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olc

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A small greenhouse. I want to run two branch 120V circuits to it.
Does it need to be a multiwire branch circuit?
Is a disconnect required at the greenhouse or at the circuits leave the main building?
Does this disconnect need to disconnect the neutral?
No grounding in this case (other than the circuit ground wire). (not a question unless the statement is wrong)
 
As far as I read it yes. Could be as simple as a double pole snap switch to serve as disconnect if your talking about a typical 15/20 amp branch circuit.
As far as running a multi wire branch circuit, sharing the neutral will then require you to disconnect both live conductors simultaneously with either a double pole breaker or two singles with handle ties at main building. So depending on how important it is to keep circuits independent of each other you may want to run seperate neutrals which is exempt from this requirement. Disconnecting neutrals not required.
Oops just thought of something, since both circuits will land on the same yoke of a device (the double pole switch) it will still require both circuits to be disconnected simultaneously. No exemption on double pole breaker or singles with handle tie.
 
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You cannot run more than one branch circuit to a separate building or structure.

That can be one 2 wire circuit or one multiwire branch circuit.
 
]A small greenhouse. I want to run two branch 120V circuits to it.
Does it need to be a multiwire branch circuit?
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Yes or install a sub panel-- section 225.30

Is a disconnect required at the greenhouse or at the circuits leave the main building?
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Yes section 225.31

Does this disconnect need to disconnect the neutral?
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No

No grounding in this case (other than the circuit ground wire). (not a question unless the statement is wrong)
Click to expand...
Correct
 
If you are under the 2014 NEC, the requirements for a disconnecting means are much simpler to meet. 2011 and before the disconnect to have approved for service entrance use (SUS), meaning it had a screw that could be used to bond the neutral. this would typically be a panelboard, and then if it has a main OCPD, you then require a grounding electrode system. There is an exception in 250.32(A) for a single or MW bc, that ground rods are not required, but this rule had to be used with 225.31 and 225.36, and the allowance for a non SUS switch was only for a outbuilding for a dwelling unit.
 
iwire said:
You cannot run more than one branch circuit to a separate building or structure.

That can be one 2 wire circuit or one multiwire branch circuit.
Click to expand...

I've been wondering something, how do you handle or interpret when a 3way switch controls a light on that accessory building that is fed from the house? And there is also a feeder to that building.
 
mopowr steve said:
I've been wondering something, how do you handle or interpret when a 3way switch controls a light on that accessory building that is fed from the house? And there is also a feeder to that building.
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They make allowances for it in 225.30(D).


(D) Different Characteristics. Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases or for different uses, such as control of outside lighting from multiple locations.
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tom baker said:
If you are under the 2014 NEC, the requirements for a disconnecting means are much simpler to meet. 2011 and before the disconnect to have approved for service entrance use (SUS), meaning it had a screw that could be used to bond the neutral. this would typically be a panelboard, and then if it has a main OCPD, you then require a grounding electrode system. There is an exception in 250.32(A) for a single or MW bc, that ground rods are not required, but this rule had to be used with 225.31 and 225.36, and the allowance for a non SUS switch was only for a outbuilding for a dwelling unit.
Click to expand...

I can't find the dwelling unit only requirement. ????
 
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