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RE: 240v primary nst?
Original poster: "Aron Koscho by way of Terry Fritz <twftesla-at-qwest-dot-net>" <kc5uto-at-wt-dot-net>
> Hey All,
> I got a hold of a 15/30 nst but the primary is 240v. I just got done
> a 240v outlet in my garage but I'm not sure how to hook the transformer to
> it. 240v lines have two 120v wires(one black, one red) and a neutral
> wire(white). Since the transformer has two bolts for the primary, do I
> simply hook both hot wires to one and the neutral to the other. This
> right to me, but since I'm not 100 percent sure I thought I might ask
> making any connections. Thanks for everyone's help.
John is right you will trip a breaker that way. Here is why: There are four
wires used in the residential electrical setting. There is the two hot wires
RED and BLACK. Both of these present 120v to ground or 240v BETWEEN red and
black. This is because the transformer out on the pole is center tapped.
There is 240 across its outer legs and 120 to the center tap from either
leg. (This is why pigs have three terminals on the side) The center tap is
grounded. The next two wires used in homes are the copper one, ground, and
the white one, neutral. Both of these wire are connected to ground back at
the box. There are only two for redundant protection. If you have an over
head feed coming into your home, you will notice only two black wires and a
aluminum wire. Each black wire is hot and the aluminum wire is
ground/neutral and is also used as a guy wire to attach the whole mess to
Hope that makes sense,