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Tony Hwang Tony Hwang is offline
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Default Current flow in main neutral vs. current through water meter

Existential Angst wrote:
"Tony wrote in message
...
Existential Angst wrote:
Awl --

The current in the main neutral *should* be the difference in current
between the main hot legs, right?
However, it is usually off by between 1 and 1.5 amps, which seems to
correspond to the current flow through/around the water meter. This
would
seem to be a *necessary* relationship, right?

My impression is that prior to the utility replacing the old wires along
the
poles and to my house, this current flow through/around the water meter
was
a lot higher -- 3-5 amps.

So the Q is: What is "acceptable" ito current flow through the water
meter
to the street?

My assumption is that if I took out the water meter, then all of the
neutral
current would necessarily flow through the main neutral, and it is just
that
apparently the water plumbing ground is "good enough" to share some of
the
return load -- which doesn't seem like such a terrible thing, esp. given
the
aluminum conductors used by the utility, vs. the copper plumbing to the
street, and perhaps farther.

But again, what are acceptable limits ito of current flow through
grounds?
Is there an NEC ratio, a percentage?
Mine seems to be pretty constant at this 1-1.5 A.

Hmmm,
Sounds like ground loop problem.


Tony, didn't you EE for NASA or sumpn?
Man, it was a miracle that moon shot didn't just crash....

Yeah, I got loads of 60 cycle hum in both hots and the neutral. What
*shall* I do????

Hmmm
I only worked on NASA computer systems. Highest ground current I ever
read was 1.2 Amp. on a 250KW M-G UPS system which we could bring down to
near zero Amp after sorting things out.