I am adding an extra wall control for the garage door opener. The company said to use 18-22 gauge doorbell wire, connecting the striped wire to the screw marked “B”, and the plain wire to the screw marked “W”.
I asked the store for doorbell wire, but it is different from the existing wire. No striped wire, for one thing; one is white and the other red. And instead of the two wires being stuck together, they are sheathed together like telephone wire. It is a little bulky and will be a tight fit.
The wire is labeled “18/2 TH”–TH for thermostat?–is that the same as doorbell wire? And is red equivalent to stripes?
Janet
Replies
Just about any 18 gauge insulated wire will work. You just need to be able to tell the two wires apart. Normally there's one wire that is plain and one that is striped or has a rib molded into it or is an entirely different color.
Generally the white, un-striped, or ribbed wires are considered to be the "neutral" (to the extent that there is a neutral in such a circuit) and the non-white, striped or non-ribbed wires are considered to be the "hot". But there's no harm if you reverse this arrangement so long as you are consistent -- the same colored wire goes to "W' or "1" or "A" or whatever on each end. And if you must join two cables with different color codes just make sure to carry the "conceptual" color to the other end.
Glad I asked. I viewed the wires as one plain and one marked, and assumed that ribbing was equivalent to striping. What about wires where one has writing and the other doesn't?
Janet
It doesn't really matter, so long as you decide which one is "white" and which one is "black" and attach them accordingly. But mormally (the only odd exception being the ribbed case) the "distinguished" wire is considered to be the hot/black/whatever. If wires are the same color but one has printing on it, that would be the "distinguished" wire.
But another thing to notice: With some older wire you may notice one wire is silver colored on the inside and the other is copper colored. The copper colored wire is the "black" in this case.
(I don't know why it got to be that the ribbed wire is "white". This was first seen on "zip cord" back, I'm guessing, in the 50s when they first started using polarized plugs. Got off to an odd start and stayed that way.)
Making a Rolodex card for this information. Thank you!
Janet
What Dan said...Yeah. If
What Dan said...Yeah.
If in doubt go to your local building supply store and ask for "lamp cord", sold in custom cut lengths.