On Friday, February 5, 2016 at 4:47:12 AM UTC-5, Texas Kingsnake wrote:
I am having my electrician buddy help me replace an old circuit box in a
fairly old house. Much of the wiring is old and cloth covered from the
40's. What happens if one of the wires we are replacing breaks or is too
short to reach the breakers in the new panel? Do those broken wires have to
be spliced with wire nuts to a new piece of wire and then the splice section
mounted in a new junction box outside of the new panel? That could get ugly
very quickly but my limited knowledge of the NEC says splices have to be
with approved connectors and inside junction boxes.

Will he have the tools to determine if any of the wiring in the house has
decayed enough to present a fire hazard? Do you measure the resistance of
the wire from the panel to the eventual load? I know that one very long run
to the kitchen reads 105 volts with the microwave on when the voltage at the
breaker serving that run is at 119 volts. This is a run that has been used,
apparently, for years with a 20A breaker even though the wire apparently is
only 14 gauge. We will be correcting that by wiring it to a 15A breaker

Also, he talked about "balancing the load" within the panel. Why is that
important?

This may sound like a stupid question but why are the breakers staggered? I
thought the A hot coming in on the left fed all the breakers on the left and
the B hot of the right fed all the breakers on the right. Apparently not.
Why?

Any other pointers on panel upgrades or sites where I could learn more about
the process? I've been watching a bunch of so-so YouTube videos, but they
don't seem to answer the questions I have.

I've already gone through the panel and marked down which wires go where by
shutting each breaker off in turn and making note of what outlets and lights
were no longer powered. My buddy said that's often the worst part of a
panel replacement. I assume the wires have to be properly labeled as they
come off the old panel and get attached to the new one. Would a Brother
label printer do the job? Would it pay to get the kind of labeling tape
that's actually heat shrink tubing? Would it be code-worthy to label each
wire like that permanently?

Some of the cloth covered original wiring looks awfully frayed. I am
guessing that it's not code to sleeve them with plastic shrink tubing but I
suspect the real fix is to replace the wire which would about quintuple the
price of this job.

Would this be a good time to check the house's grounding system? How do you
measure the quality of the house's ground?

I'm assuming that he's going to know all of this stuff, but I'd like to be
as well-informed as I can about what problems we might be facing since I
will be assisting (mostly holding the flashlight or heading out to Home
Depot if we don't have everything we need).

I was also wondering if it would be prudent to place an externally mounted
shutoff for the whole house between the meter and the box? As it stands now
any work on the panel involves disconnecting the smart meter and a shut-off
would eliminate that step.

Thanks in advance for any advice . . .

TKS

what the OP is using power wise can be meaningless.

at home sales time the buyers inspector will flag stuff, like no outlet for future garage door opener

the buyer can ding you sales price, and that costs you money