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Breaking Ohm's Law

Breaking Ohm's Law

Breaking Ohm's Law

(OP)
In a 3 phase wye configuration of loads (let's say electric resistance heaters since I have a photo of one of those)...

http://members.cox.net/rifter1/images/3pshDiag.jpg

voltage is 480V. now, just the way 3 phase works, the potential at the centerpoint in the diagram is zero to ground.

However in reality it isn't wired as shown in the wiring diagram, it's wired as this photo shows...

http://members.cox.net/rifter1/images/3pshcu.jpg

The two curvy black wires at the top represent the center point of the Wye. However here is the dillema... I read zero volts to ground from any of those three terminals with the curved wires (as expected) however the wires are drawing 8 amps.

I know why there is zero potential between the phases and ground, the sum of all the vector angles of the 3 phases at any given point in time is conveniently zero. But Ohms law stating that current is directly proportional to voltage just seemed a little odd.

Can anyone explain this?

RE: Breaking Ohm's Law

The wires are not connected between the Wye point and ground - they are in series with the heater element.

The current in these wires will be proportional to potential between L1 and the Centerpoint (or L2 or L3)

RE: Breaking Ohm's Law

rifter1 "Ohms law stating that current is directly proportional to voltage" is true only for a resistive load.  As soon as there is any reactance there is a phase angle between voltage and current.  There is a diffeence between VA and VAR.

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