On Jan 15, 10:41*pm, gregz wrote:
gregz wrote:
DerbyDad03 wrote:
On this week's episode of Ask This Old House, an electrician was
replacing the service wire and panel in a house. There were code
problems within the panel (broken breakers, doubled up circuits, etc.)
There were at least 3 generations of wiring at the panel: BX cable,
cloth cover Romex and modern Romex. There was a rat's nest of wiring
in and around the panel.

He noted that he would normally mark all the wires before removing
them but since the existing labeling was wrong, he chose to simply cut
all of the wires and "figure it out afterwards".

As he was connecting the wires to the new breakers he used this simple
method to determine which wires to connect to which breakers:

"There are 3 sizes of wires. The smaller wires go to the 15A breakers,
the mid-size wires go to the 20A breakers and the largest wires go to
the 30A breaker."

Doesn't this seem to be an oversimplified, possibly dangerous, method?

Since it was obvious that whoever came before him violated codes by
doubling up breakers and who knows what else, isn't it dangerous to
assume that the correct wire sizes were used as the mess grew over the
years?

Maybe they were just saving air time by using that explanation, but it
seems to me that a lot more investigation should have been done as
opposed to simply letting the wire size determine the breaker size. To
even imply that the wire size is the determining factor seems
irresponsible on their part.

In my house, a 12 gauge might feed a 14 gauge circuit. So, whether that is
legal, don't know. I do know it exists. That circuit might have been on a
15 amp breaker, and it should have been noted.

Greg

I also installed 85 foot of 10 gauge wire to my garage. Does not mean to
use over 20 amp breaker.

Greg

When a panel is well marked and distances of a run are known, you can
size a breaker based on the designed and intended capacity of the
circuit based on the over-sized conductor being used to combat voltage
drop...

But on a panel where every circuit except for the 240 volt appliances
was double tapped ?

Right, it would cost more than the panel replacement to trace down all
of those circuits and examine every junction on each line to assess
that situation -- all that has been described was the service upgrade
from 100amps to 200amps and the breaker panel replacement...

This is why people who see a shiny new electrical panel in a house
shouldn't be taken in an ASSUME the house has been "rewired" when
the only work which was done was that the electrical service and panel
were replaced...

~~ Evan