two conductors in parallel (1/0AWG each) how do i terminate them on a 3ph CB?

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i have a load big enough that requires two 1/0AWG cables in parallel. NEC 310.4B allows to install both conductors if 1) are the same lenght; 2) have the same cond material; 3) are the same size; 4) have same insulation; 5) are terminated in the same manner.
how do i terminate them on a circuit breaker with one entry per phase?
I was told to use a dual barrel lug, but all i can find online seems to be for bolted connection (see picture attached) not a female connection for the breaker. could you help me? thanks!!
 

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iwire

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Staff member
Location
Massachusetts
Normally we order correct two barrel lugs from the breaker maker.

If you cannot do that my suggestion is some sort of polaris splicing conductor that will accept the two 1/0s and one larger conductor to make to the breaker.

Splicing in panels is allowed, if you don't have the space you might have to do it out side the panel.
 

Carultch

Senior Member
Location
Massachusetts
i have a load big enough that requires two 1/0AWG cables in parallel. NEC 310.4B allows to install both conductors if 1) are the same lenght; 2) have the same cond material; 3) are the same size; 4) have same insulation; 5) are terminated in the same manner.
how do i terminate them on a circuit breaker with one entry per phase?
I was told to use a dual barrel lug, but all i can find online seems to be for bolted connection (see picture attached) not a female connection for the breaker. could you help me? thanks!!

If you are going to connect a lug such as your image, you'd need to do so in a manufacturer-approved (and possibly listed) manner.

A common field-solution I see and recommend, is to use a Polaris insulated tap connector, or similar. It contains an assembly of setscrew lugs, surrounded by a plastic insulator, and contains plugs for the setscrews and unused ports. You'd be using a 3-port device, with one of the ports used for connecting the minimum ampacity size to the breaker, and the remaining two for connecting the outgoing wires.

Generally, 200A and less breakers are built for only one wire per phase. 400A frame size breakers are common to be built with the ability to accept two wires per phase. Usually options of two small wires (aught sizes) or one single large size, possibly up to 600 kcmil. You might see a "snowman" lug, or you might see a lug block that has a big and a little opening.
 

infinity

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Staff member
Location
New Jersey
Occupation
Journeyman Electrician
As others have stated just order the CB with the correct terminals that accept two conductors or get a field changeable lug kit to convert the single conductor lug to a two conductor. Or if all else fails do something like this:

rMwd-1kJMV0G33uUDx_XBNUTyJxwSaFtJivkK94z5wnAi1VSKyhiJQJGk56w6Myh1zq6DAXszktutOsLGesKZRqJm5VC65bwKxhFFqqIdcYBHiFE9kiuh2MwsZigr1pUeuAaRP3Tp13R7h5kWdVUQcce_VGOmvZB1sWI0rJ-3b28mpvQ9i-_LGmhSL3NK7Dq5d-xsLanW6DV5ILFbnZcW889t5sS-mVgN4cMdATnPC1EgYx3GLFwEtv9Lu1c5nQvdZ_BvEwnlUVqB2bcmaY_0IxCZbHTxP24seZPbRBqY7iC5ycxCbHNKZ_7pNVXh8pRChSuPgflHIx5wX_0JxJEumhMWy_J42t05dShxqWk7xsuneGPSz4FJ2YYddCBZlbl9zjPlJNZUUq0a7fFw_zqesJYWF-GS2C8ZNNw5H0Qcon-aGKldq-vokUhfvOB9A04lxDyT9DYfRr6mceXt4YBdVqyG56b8uJo-LM1xL1eQTfLDljjp-myanYrrN073I99X27xBtdYLWPjuJTNfO3aARsKs2adbSOdRkkxF-gOcit69JazJT63DZGXeegoerc8LQinh2wWqqQZT64cSyuNhiWpzADfrp8=w1035-h1380-no
 
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