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Doug Miller

In article , wrote:
10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex type
cable has a ground which is not referenced as an "official: conductor. 10/3
cable has 3 10awg power carrying conductors and a ground. The 3 conductors
are white (neutral) Black and Red (hots) and is used in balanced 240/120
volt circuits (120 from each hot to neutral, 240 across the hots)

All correct up to this point, but now you go astray:

10/2 has a white and black and is used in 120volt circuits only.

Completely incorrect. Since a 240V circuit has no neutral conductor, only
two hots and a ground, 10/2 with ground is perfectly fine for use in 240V
circuits up to 30A. Three-conductor cable (such as 10/3) is needed for a 240V
circuit only if there are also 120V loads on the circuit; an example of this
would be an electric dryer, which has 240V heating elements and (typically) a
120V motor. The 240V motors which are typically found in woodworking tools
have no neutral, only two hots, and will get along just fine on circuits wired
with two-conductor cable.

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Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.