225.30 - is it ok if running 3 branch circuits to a detached garage

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fandi

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Electrical Engineer
Hello All,
Per 225.30, multiwire branch circuit shall be considered a single circuit. And per Art 100, Definitions, multiwire is a branch circuit that consists of 2 or more hot conductors. So I can run (3) 120V circuits (for example #1, #5, #9) to a garage without having to install a sub-panel?
Thanks.
 
Not unless you have 3 phase at your house, use a shared noodle for the 3 hots, each hot is on a different phase, and you use a 3P breaker or handle tie 3 SP together.

Prolly not I assume.

What you may do is run a single MWBC to a detached structure, which for resi is 2 hots, one from each leg, and a shared neutral. 2P breaker or handle tie needed.
 
fandi said:
Hello All,
Per 225.30, multiwire branch circuit shall be considered a single circuit. And per Art 100, Definitions, multiwire is a branch circuit that consists of 2 or more hot conductors. So I can run (3) 120V circuits (for example #1, #5, #9) to a garage without having to install a sub-panel?
Thanks.
Click to expand...

You left out the sharing a neutral part. For 1Ø, 120/240 circuits #1-#5-#9 would all require separate neutrals so the answer is no.
 
infinity said:
You left out the sharing a neutral part. For 1Ø, 120/240 circuits #1-#5-#9 would all require separate neutrals so the answer is no.
Click to expand...
1 5 and 9 in a three phase panel will use all three phases - good luck finding appropriate handle tie though.
 
fandi said:
. . . per Art 100, Definitions, multiwire is a branch circuit that consists of 2 or more hot conductors.
Click to expand...
I suggest you go back and read that definition more carefully (i.e., I am invoking "Charlie's Rule"). It requires each hot conductor to be on a different phase. In a 120/240V single phase panel, circuits 1, 5, and 9 are all on the same phase (i.e., have zero voltage between them). So no, you can't do that.

 
infinity said:
You left out the sharing a neutral part. For 1Ø, 120/240 circuits #1-#5-#9 would all require separate neutrals so the answer is no.
Click to expand...
Thanks Mod. I just install a sub-panel at the garage and then for ground: drive a new rod or tie to the cold water pipe. Is there any separate disconnect required between the main panel and the sub-panel or the main breaker at the sub-panel would suffice?
 
You need a building disconnecting means at the remote building. A main breaker in its sub panel will satisfy that requirement.
 
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