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400watt HID light fixtures

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EFX

Electrical
Feb 1, 2003
2
I recently found 32 amps of load on phase B of a 480v 3phase panel
the puzzling thing is no lights are on nothing seems to be on to create this load
my question is , is it possible the ballasts in the field are drawing this current, even though the other 277v leg is not energized to allow the light fixtures to go on
 
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You stopped making current checks too soon. The next logical step is to test branch-circuit currents. Good luck.
 
Measure current in ground and neutrals too. If you find current in ground, you may have a ground fault with high impedance..
 
DOES A 120V DIMMER AFFECT THE PROTECTION of a gfi recepticle
 
EFX,

Does your post have anything to do with this thread? If not, start a new one. That way, discussions remain focussed on the subject at hand.



----------------------------------

If we learn from our mistakes,
I'm getting a great education!
 
"is it possible the ballasts in the field are drawing this current, even though the other 277v leg is not energized to allow the light fixtures to go on"

You seem to be under the mistaken notion that a 277V ballast uses 2 "legs" of 277V current. 277V is derived betwween 1 leg of a 480/277V system and neutral. So what you are asking is not relevant, there is only 1 "hot" leg going into those ballasts.

No go back and follow busbar and rbulsara's advice. You have something drawing power, and if it is only on 1 leg you were correct in suspecting a lighting circuit, but that is not absolute. You need to isolate which branch circuit the drain is happening in and work from there.

"Venditori de oleum-vipera non vigere excordis populi"

 
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