need code # from 2002 book
#1
need code # from 2002 book
does anyone know where in the code book that it says 120volt and 277volt that you would need a divider in junction box?
#5
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See 404.8(B). If you exceed 300V between adjacent devices, then you are required to have a barrier. Normally this comes into play with 277V switches from different phases, which have 480V between them.
With mixed 480Y/277 wiring and 208Y/120 wiring, you can have anything from about 150V to 400V between a random 277V hot and a random 120V hot, and about 2/3 of the time you will exceed 300V and a barrier would be required.
Note that this barrier is between the switches only, and is not required in the raceway.
I'd suggest also noting 200.6(D) identification of the grounded conductor (neutral)
-Jon
With mixed 480Y/277 wiring and 208Y/120 wiring, you can have anything from about 150V to 400V between a random 277V hot and a random 120V hot, and about 2/3 of the time you will exceed 300V and a barrier would be required.
Note that this barrier is between the switches only, and is not required in the raceway.
I'd suggest also noting 200.6(D) identification of the grounded conductor (neutral)
-Jon