Two 20A GFI breaker circs (separate Neutrals) in 12" bury conduit.

[James L]

IMO, a multiwire branch circuit is not 240v. A multiwire branch circuit can be considered 2 120V circuits. The table doesn't state the voltage in the conduit. It mention residential branch circuit 120v or less.

I don't see any way 1 circuit can be counted as 2

It's "multi wire branch circuit"

The plural is on "wires", but "circuit" is in the singular.

If you have load on both hots, there is hot-to-hot voltage. That makes it one circuit

 

[wwhitney]

I don't see any way 1 circuit can be counted as 2

Because the NEC says so: as mentioned earlier, 240.4(A) says "A multiwire circuit shall be permitted to be considered as multiple circuits."

Cheers, Wayne

 

[LarryFine]

That's correct. It's one of the few rules that we can use whichever way is more beneficial to us.

 

[James L]

Because the NEC says so: as mentioned earlier, 240.4(A) says "A multiwire circuit shall be permitted to be considered as multiple circuits."

Cheers, Wayne

 

[James L]

Because the NEC says so: as mentioned earlier, 240.4(A) says "A multiwire circuit shall be permitted to be considered as multiple circuits."

Cheers, Wayne

Which year are you looking at?

It's not in 240.4(A) for 2017

I don't recall ever seeing it

 

[suemarkp]

Try 210.4(A): Branch circuits recognized by this article shall be permitted as multiwre circuits. A multiwire circuit shall be permitted to be considered as multiple circuits. Except as permitted in 300.3(B)(4), all conductors of a multiwire branch circuit shall originate from the equipment containing the
branch-circuit overcurrent protective device or protective devices.

 

[jaggedben]

In the particular context at issue for the OP, 225.30 says "For the purposes of this section, a multiwire branch circuit shall be considered a single circuit."

 

[jaggedben]

Because the NEC says so: as mentioned earlier, 240.4(A) says "A multiwire circuit shall be permitted to be considered as multiple circuits."

Cheers, Wayne

You must mean 210.4(A).

 

[wwhitney]

In the particular context at issue for the OP, 225.30 says "For the purposes of this section, a multiwire branch circuit shall be considered a single circuit."

Nice, that supports the idea that an MWBC can be simultaneously one circuit for the purposes of applying 225.30, and two circuits for the purposes of applying 300.5.

Cheers, Wayne

 

[jaggedben]

Nice, that supports the idea that an MWBC can be simultaneously one circuit for the purposes of applying 225.30, and two circuits for the purposes of applying 300.5.

Cheers, Wayne

Issue resolved!! My 2-pole GFCI breaker idea works.