DIYbanter - View Single Post - Knob and Tube BETA-33

Bud--

wrote:
(From Beta-33,34,35 -- from a different computer using Google Groups -
yuck)

This probably doesn't help, but when I did the continuity check a long
time
ago, this is what I found:

I tested for continuity with all wires disconnected at both 3-way
switches
and with the hallway lightbulb not in the socket.

At the 3-way switch at the bottom of the steps, I numbered the 3 wires
as 1,
2, and 3.

At the 3-way switch at the top of the stairs, I found wires with
continuity
with two of the downstairs wires, and numbered them as 1 and 2 (the
wires
they connect with downstairs). I numbered the third wire on the
upstairs
3-way as number 4.

At the hallway light, I numbered the wires as 3 and 4. Number 3 has
continuity with number 3 on the downstairs 3-way switch, and number 4
has
continuity with number 4 on the upstairs 3-way switch.

If measured right, some 3-ways were connected as your measurements
indicate. Either 1 or 2 is the neutral, the other is the hot (the blue
wires on Terry's diagram). The odd color on the switch goes to 3 and 4.
In operation each side of the light is switched between hot and neutral.
When both sides of the light were neutral, or both hot, the light is
off. It is not code compliant to wire a new light this way now, but
3-ways sometimes were wired this way long ago. [Anyone know if it was
ever code compliant?]

Probably harder to troubleshoot because the open connection may be
further away - it affects the hot feed to both 3-ways.

-------------
You may have noticed halerb has a fethish about K&T.

--
bud--