"bud--" wrote in message news:53084114$0$59830$c3e8da3
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Making a map with device locations and circuit number is real useful,
but a PITA. Would give you an idea where the first device is.

If you AFCI the first receptacle and wire through the rest, the device
protects the wiring downstream. All the load is at or downstream. The
AFCI receptacle will protect the wiring back to the panel from series
arcs (loose connections) by disconnecting the load that maintains the arc.

After thinking about the for a while, I realized I could use my X-10 signal
strength meters to discover the first outlet on a branch circuit. If I
place a test transmitter on another branch, the X-10 meter will show
noticeable signal attentuation as measurements are taken at each outlet on
the branch circuit in question. I often use that technique to "zero in" on
noise generators. As you move closer to the noisemaker the noise reading
function of my XTBM meter shows an increase in the noise signal level (in
millivolts). Never thought the technique could ID the first outlet in a
circuit, but I think it will.

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I was under the impression, probably wrong, that if you connected a
secondary buss bar with a large gauge wire (#8) to the neutral buss bar
that
it was acceptable to land neutral wires on the secondary buss bar but
now I
am not sure where I read that or if it's true. I realize now that the
OEM
neutral bar on my Square D panel sits above all the breakers and looks
to be
isolated from the enclosure.

I assume that if there is a wire-connection that would work. You have to
figure out what size wire is appropriate. Slight chance an inspector
might object to using something the manufacturer calls a "ground bar" as
a neutral bar.

I had the panel inspected after I installed the first set of dual skinnies.
But I think at that time I had moved all the ground wires from the panel's
legit neutral bar to the ground bar. I was mostly concerned at the time
that the inspector would disallow the dual skinnies because of the potential
to overload the panel. It was obvious from what I had done, though, that I
was relieving the older cloth-wire circuits of heavy loads (like toasters)
and using the new 12/2 romex instead. The overall load on the panel wasn't
changing, just the distribution of that load. Which brings up another
subject. Today with my tong meter I realized that one side of the panel was
pulling way more amps than the other. I guess that's for another thread,
too. What happens when a circuit panel is unbalanced and has substantially
more of a load on one leg than the other?

Since the last inspection I have added more circuits but the overall load is
still way less than the total the panel is rated for. Unfortunately now the
neutrals are connected to the auxiliary buss bar and not just the ground
wires and I recall that was new work, post inspection.

A subpanel near the service panel is another possibility. (But then you
will never be able to sell your house - according to one opinion. And
you won't be able to get insurance. And a house inspector may say the
house should be torn down. And it should be torn down. And that does not
include the shame of having a subpanel.)

No subpanels for me! A long time ago I decided that this house would
probably have to be "gutted" when sold so it's not a big issue. Part of the
problem is that it was built in 1941 when there was a shortage of everything
and those shortages were reflected in the materials used in the house. No
building paper between the floors, badly cured wood on the roof, etc.
Fortunately where I live the land's what's worth the most $ and houses like
mine are often knocked down so that larger homes can be built to replace
them.

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I am not sure what you mean by "other than in a service panel, they have
to
be insulated from the enclosure."

In a service panel the neutral and enclosure are connected together.
Could be a wire. Often is a screw and looks like a mounting screw but
may be green. If the neutral and enclosure are bonded, an added neutral
bar would not have to be insulated from the enclosure (but may not rely
on the enclosure as the electrical connection back to original neutral
bar).

Gotcha. I may be safe after all. The question now is whether to double up
all the ground wires on the buss bar I installed (with the number 8 wire
connected to the panel's original neutral bar) or to install another ground
bar on the left side of the panel. I am leaning toward the latter because I
don't like the idea of disturbing the old wires yet again and because
there's a lot more free space on the left side.

In a subpanel, an added neutral bar must be insulated.

Another reason not to endure the shame of a subpanel.

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Someone mentioned thermally protected outlets that cut out when they get
too
hot. I've never heard of them. Are they something standard in the
industry? Would they offer protection against high resistance
connections
that the AFCI's don't seem to provide?

I have never heard of thermally protected outlets. Is that feature UL
listed?

Dunno. I'll first have to look up where someone mentioned them here and
then go on to Google to find out more. They have to be pretty simple to
build - just needs a klixon internally to interrupt the circuit in case of
an overheat. Look for that in a separate thread as the initial search
turned up a number of likely candidates. There's probably a third thread to
evolve from this. Is UL listing necessary for approval of the installation
of auxiliary equipment like an X-10 coupler/repeater? Now I remember why I
haven't invited the inspector back . . .

And AFCIs may trip on a ground fault caused by a "glowing connection",
or if a glowing connection turns into an arc.

A temperature "aware" outlet seems to be the solution to glowing
connections. More in a new thread.

Thanks for your input, Bud.

--
Bobby G.