On 12/07/10 2:19 PM, Bill wrote:
On 12/7/2010 1:41 PM, FrozenNorth wrote:
On 12/07/10 1:16 PM, wrote:
On Mon, 06 Dec 2010 23:02:40 -0500, wrote:

Scott Lurndal wrote:
writes:

To avoid "cycling the breakers", Lew advised running 12-3 from two 20
Amp breakers (it would not have occurred to me to do that).

I'm not sure what this means, but if you're running two 120v circuits
using 12-3 from a pair of 20A breakers, make sure the breaker handles
are tied together such that both trip if either one trips.

scott

Because???

Because 1) - it is code.
2) if one circuit trips and you assume the wire is "dead" you
could be - the black could be dead, and the red live, and a lifted
neutral (which is common to both) would be LIVE.

Why not use a 240V breaker, with 12/3, then there is no issue with tying
the handles, you still get two 120V circuits. Sounds safer to me, but
not sure about code.


I think the original explanation provided was to "avoid cycling the
circuit breaker". I don't have a basis for an opinion on this.

Nothing stopping you from feeding two 120V switches with the 12/3, then
two separate runs of 12/2 to your fixtures.

--
Froz...


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