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Hooking up power monitoring. Cts are around the 480v lines in the panel. We put a transformer in the reference voltage line that takes it down to 240v. Does that seem wrong to anybody else? Doesn't the reference voltage get used to calculated power. Won't this only be half?
 

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Bilge Rat
motors and controls.........
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It depends on the equipment. A lot of power monitoring uses PTs (Potential Transformers) that reduce the line voltage to 120. It's almost always two PTs connected open delta with phase B grounded.

Usually, there's some way to program the system for either the primary voltage or the PT ratio.

Pay attention to polarity, if any of the PTs or CTs are backward, the readings will be inaccurate.
 
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