On Mon, 12 Sep 2005 14:51:14 GMT, RoyJ wrote:

I would ALWAYS put in the full 4 wires especially when you are talking
about NM or UF cable. The cost is minimal, the labor and access is
usually a bummer. If you are pulling it though conduit, I might let it
ride for a while.

In the lab at school we have a 200 amp 3 phase bus duct, they cheaped
out when building the place, ran 3 hots and a ground with no neutral. In
order to put the neutral in we would have to pull all 4 wires out, add
the neutral, pull all 5 back in. Dumb.

Grant Erwin wrote:

Alex wrote:

I am pulling a new 220V line from a power box for my new belt grinder
(20Amp 115/220V). Wiring is inside my garage and 8 gauge wires go
through conduit. San Francisco code requires 4 poles for 220V
appliances so I am using four wired inside conduit.
My question is how to wire switch and motor to four wires.
Motor wiring has 6 wires but instruction says that 3 wires go to one
pole and 3 other to another. What about ground and neutral?

Is there any good on line DIY manual for this kind of work.


4 poles would go to a dryer outlet, which has L1, L2, N, G

L1: first 220V line
L2: second 220V line
N: neutral -- voltage L1-N or L2-N is 120V
G: ground

I would never go to the expense of running 4 wires when you only need 3.
Nor do I believe that San Francisco code actually requires it, but there
are amazing things in California laws. Your motor will use L1, L2 and G,
of course.

GWE
Because the grinder uses 110 volts for the light, the code WILL
require 4 wires. Running the light from either L1 or L2 to ground will
work - but it will NOT meet code - in California or in Canada.