D. Gerasimatos wrote:
In article ,
Chas Hurst wrote:

I think it's reference to insulation or lack of. With no insulation
the wire dissipates heat faster, hence the higher rating.


Knob and tube is insulated. It's exactly what I said. The gauge of the
wire is thicker. K&t used 12 gauge wire for 15 amp circuits. Most 15
amp circuits now use 14 gauge wire.

You are right that it is insulated. Of course by now a lot of it is not
all that insulated.

However you are at least a little off on the wire gauge thing. I am
not quite old enough to know if they originally required or used larger
gauge wire for a circuit. The stuff I have worked with did not. In fact it
used smaller gauge wire. The physical separation and the ability to
dissipate heat allowed it to carry the additional current per wire size.




Dimitri

--
Joseph Meehan

Dia duit