Posted by Steve Spence on July 3, 2003, 1:57 am
ours isn't too bad. white is neutral, black is hot. very few devices use
220vac. electric hot water heater, clothes dryer, electric stoves, and air
conditioners being some exceptions. everything else is 110vac and easy to
Posted by Ken Finney on July 2, 2003, 4:00 pm
What am I missing here? This problem was a big deal 15 years ago, and many
people spent a lot of time getting the NEC changed to allow the use of 240
Volt (USA) receptacles to be used for low voltage (provided there aren't
real 240 Volt circuits in the house). This is a lot like discussing what
the standard size of notebook paper should be: the decision has been made,
live with it.
Posted by Scott Willing on July 2, 2003, 11:56 pm
On Wed, 2 Jul 2003 16:00:37 GMT, "Ken Finney"
Agree, but it comes up again and again anyway. Is there a FAQ for this
BTW, when I bought a bunch of those I asked an RE supplier what the
convention was for polarity. They didn't know so I picked my own. Is
there a recognized one?
Posted by Jordan Hazen on July 4, 2003, 8:53 pm
[re: using 240V receptacles for DC circuits]
The common convention seems to be positive on the "hot" (brass screw),
and negative on "netural". This makes sense, as if either DC leg is
grounded it's usually the negative one... except in telco facilities.
DC CF bulbs with a standard Edison base are set up the same way,
expecting +12V at the tip.
When wiring some of these up recently, I considered tying the neutral
and ground contacts together on both ends, to reduce voltage drop a bit,
but wasn't sure if the NEC allowed it. Assuming battery-negative is
grounded, do the "groundED" vs. "groundING" conductor separation
requirements still apply to DC circuits? I've yet to encounter a DC
appliance that needed a dedicated ground wire.
Posted by Steve Spence on July 3, 2003, 1:58 am
Most houses have 240 (220) vac circuits, so the standard 220vac connector
isn't code compliant, for low voltage dc.