From: Wayne Whitney
Date: 9/22/2004 12:57 AM Easte


OK, I guess I used the wrong term, I meant to say "different types of
conduits". Sounds like EMT with THHN wire is the way to go, I was
just curious about the alternatives.

Emt is the easiest and most efficient way to go.


Now you have left out here the most important thing of all. What are you
wanting
to run or plug into these receptical and what will be the amp draw of them?


Yes, that's true, I was trying to get a handle on EMT before I got to
the details. Thanks for the responses.

Here my situation: the main loads will be a table saw (15 amp 120V
universal motor), planer (15 amp 120V universal motor), dust collector
(8 amp 240V induction motor) and jointer (6 amp 240V induction motor).
[BTW, both the DC and jointer claim to 1 HP. Is the jointer motor
really 25% more efficient?] There will also be a 120V air compressor
and miscellaneous portable tools.

I was planning on 1 240V 20 amp circuit and 2 120V 20 amp circuits,
because other than the dust collector, I'll mostly be using these
tools one at a time. I'm happy to have the jointer next to the dust
collector, so they can share a duplex receptacle. My planned physical
layout is this, along a 20' wall:

Quad 120 Quad 120 Quad 120 Electrical Panel
Duplex 240

My preference would be for each quad 120 to be two duplexes on
separate circuits. I'm a little confused about running multiple
circuits in the same conduit. Namely:

Are there any rules that if multiple circuits are in the same conduit
or box, they have to be shut off by the same breaker?

No. The only time a breaker has to be common tripped with another is when the 2
circuits are connected to the same device YOKE.

IOW - a 220v receptacle is on one yoke. It's breaker must have a common trip.

A duplex receptacle split into 2 circuits by removing the jumper tab would be
considered 2 circuits on one yoke, and the breakers would have to common trip.

A combination device at your back door, with 2 switches on it both on the same
yoke, one fed by one circuit for the back door light and the other for the
power to your backyard shed which is on it's own circuit, would have to be
common trip.

Is there
anything special about having a wire run through a box without being
tapped?

Nope just pass it through.


If I run 2 separate 120V circuits in one conduit, do I end up with two
white wires and two black wires? Or am I supposed to use different
colors for each wire?

In residential both hots can be black, but you could use a black for one
circuit and a red or blur for the other if you desire.

You will have 2 neutrals and they must be white.


If I run all three circuits in one conduit, then that's 6 conductors
plus ground. Do I have to derate the conductors, and does that mean
using #10 gauge THHN for a 20 amp circuit?

No.

Thanks,
Wayne