"Ralph Mowery" wrote in message
k.net...
In article ,
says...

On 07/01/2017 07:08 AM, Sherlock.Homes wrote:
Seems to be 120vac from red to ground and 120vac from black to ground
but no
voltage between red and black, which should be 240vac. Reading was
taken at
the external dissconnect. What might cause this?

Thanks,
S


If red is L1 and black is L2, it seems like you don't know how to use a
volt meter properly.

If the disconnect is not thrown , UM could be right, something is
letting the voltage through to the other side.

I did a lot of reading on this and UM is right - it's called backfed voltage
and it's a problem peculiar to 240V wiring. It could easilt account for the
problem since the circuit label shows a crankcase heater.

If the disconnect is thrown, then one side is the real voltage, and the
other side is probably the 'phantom' voltage caused by the high
impedance of the meter picking up the induced voltage on the wiring.

One side could be open somewhere.To find out which, take a light bulb,
anywhere from a couple of watts up to 100 watts and put across the line
from L1 to neutral and then L2 to neutral. Do that on the 'hot' side of
the disconnect.

Could be the breaker is bad, needs to be reset, or if fuses are used,
one bad fuse.

Checked the fuses, checked the breaker but couldn't find anything wrong.
Wife is insisting I call the pros. Will let you know what they find.

S