ECN Forum Forums General Topics of the Trade General Discussion Area what is out of phase ?

'73,

As Steve said, you got that last bit backwards.

If you wire a 240V circuit it has to be to a double-pole breaker which connects to both busbars.

Or are you confusing "busbar" with the left and right sides of the panel? It doesn't work one busbar for the left, one for the right. They are interleaved on each side (i.e A-B-A-B-A-B etc.), so any two adjacent positions will be on opposite hot lines.

Thus you could also get a 240V circuit from two adjacent single-pole breakers, with their handles tie together so that any overload disconnects both hot lines. (I think that's allowed by the NEC, but as I'm not in the U.S. I'll wait for the others to confirm or deny.)
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George,

Velocity and differential phase shift is a big problem in wideband telecoms circuits. When I was working at Goonhilly we had all sorts of difficulties with this on mal-adjusted equipment.