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.

--
EA

On Nov 27, 11:10*am, "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.

--
EA

Doesnt that mean you have a short, that is wasting-loosing 1.5a.

On Nov 27, 11:10*am, "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.

--
EA

Seems to me current flow through a water meter is not at all
permitted. In fact, our local code calls for a heavy copper braid
bypass around the meter connecting copper supply line to house copper
plumbing. In addition, a 4 ga wire connects the input copper line to
the ground/neutral lug in the meter base. Of course, there is also
the usual long ground rod with 4 ga to the meter base. I get a nice
124.5 V both sides of the line on my Fluke 27. If I disconnect the
wire at the input water line, then I could be measuring current in the
fashion OP describes without bothering the meter, right? This might be
some measure of the ground rod/neutral efficiency. Maybe its just
academic but interesting.

Joe

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 Hwang wrote:

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.

Electricity will take all available paths, so some current flow between
the ground at the pole and your ground rods and / or water pipes is to
be expected. This is the reason that jumpers are required around water
meters so the meter guys don't get fried removing the meter.

"Tony Hwang" 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????
--
EA

"Pete C." wrote in message
ster.com...

Tony Hwang wrote:

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.

Electricity will take all available paths, so some current flow between
the ground at the pole and your ground rods and / or water pipes is to
be expected. This is the reason that jumpers are required around water
meters so the meter guys don't get fried removing the meter.

Apropos of Joe's reply, I used the phrase "thru the water meter" for
visualization -- I indeed have jumps, altho #4 seems a bit over-gauged. I
have #12's in a variety of places, across the meter, and from various pipes
to before the water meter, street side.

My understanding is, tho, that experienced plumbers et al dealing with water
meters bring their own jumper cables to establish a bypass. I know *I*
would -- after all, how do you know for sure that a home-moaners
ground/bypass is actually working/conducting?

I'm also going to follow Bill's suggestion, and see what the amprobe reads
grouind-wise (and main-neutral-wise), when my power is shut off.
There IS, in fact, a single errant wire between my neighbor's house and
mine, embedded in some now-rotted mortar.
Hmmmm, the plot thickens, eh?
I'll ampprobe that wire as well.
--
EA

On 2009-11-27, Existential Angst wrote:

The current in the main neutral *should* be the difference in current
between the main hot legs, right?

If there are no other return paths, that is correct. Although as you
have observed, in communities with interconnected water supply piping,
the water supply piping may be a very good return path (via the
various neighbors' neutral to grounding system bonds).

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?

Again, if those are the only two return paths. However, there may be
more or less current on the metallic water supply, contributed by your
neighbors.

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.

That makes sense. If the service drop was higher resistance, less
current goes on the service drop neutral, more current on the water
supply ground to your neighbors' neutrals.

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

There's not a good answer to this question. Cetainly your service
drop neutral should be taking more of the current than your water
supply pipes; if not, there's a problem with your service drop
neutral. Beyond that, it is what it is.

[Depending on the local practices for your water serive, you could
take steps to eliminate the return current on the water supply. For
example, here the water meters are in shallow vaults in the sidewalk;
if you install a non-conductive coupling on the house side of the
water meter, then you disrupt the return path, while retaining the
buried water lateral as a grounding electrode. But be careful about
disrupting the return path, see below.]

My assumption is that if I took out the water meter, then all of the
neutral current would necessarily flow through the main neutral

Yes, but you would have to be very careful about doing this, since as
soon as you disconnect the water meter, there will be a voltage
difference between the two sides of the water supply, representing the
voltage that was driving the current. You could be injured or killed
if you get across the two sides of the water piping. This can happen
even if your main breaker is off, since a neighbor's neutral could be
faulty and could be using your neutral as the principal return path,
via this water pipe bond.

But again, what are acceptable limits ito of current flow through
grounds? Is there an NEC ratio, a percentage?

Nope, the NEC doesn't directly provide a ratio or say to what extent
this is acceptable. It is, however, a side effect of the NEC
requirements on grounding and bonding.

Cheers, Wayne

Existential Angst wrote:
"Tony Hwang" 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????

NASA uses tricycle gear to eliminate ground loops.

Speaking of elimination, that's what I needed to do while I was
monitoring my water meter the other day. When I got back, there was
current going through it.

I, too, have loads of hum between my hots and neutral. I discovered a
way to get rid of it, but then my stereo wouldn't work.

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.