Basic Fluorescent re-wire

[Scott H in Wheaton]

I have three 8 ft twin-tube fluorescent fixtures on my garage ceiling.

I am replacing the old ballasts with electronic ones.
I made the mistake of starting this project a long time ago, getting away from it, but now want my lights to work again!

Line power comes in at the south end of the center fixture. Black and White wires go to the Black and white wires on the new ballast. The outer two fixtures have their Black and white wires coming in to the north end of the center fixture.

I just hook all the white wires together and all the black wires together, right?
I know, dumb rookie question but I figure its better to ask than be sorry.

As a follow-up question, I can now light the center fixture but one tube only. I changed the bulb and still only the one tube lights. I remember seeing a puff of smoke from the socket that no longer works. The sockets on that end have two wires, but the sockets on the other end only have 1 wire. Do I need to swap out the sockets for the kind with just 1 wire? If not, what do I do with the extra wire of the two wire kind? The bulbs have a single pin at each end.

Thanks ever so much in advance!

 

[ForceFed70]

As a general rule of thumb - yes, tie the blacks together and the white's together. BUT, nobody knows exactly what you and previous owners have done so nobody will be able to answer for sure.

 

[Scott H in Wheaton]

As a general rule of thumb - yes, tie the blacks together and the white's together. BUT, nobody knows exactly what you and previous owners have done so nobody will be able to answer for sure.

Thank you...These were installed by an electrician about 12 years ago. All new metal conduit and wire along with a new circuit breaker box. I am just trying to put it back together the way he had it, and like I said in my post I mistakenly took it apart a long time ago ( maybe 2 years?).

 

[Scott H in Wheaton]

Started in on the project again this morning. Always nice to clear the cobwebs and get a fresh start.

I connected all the black wires and white wires and now the two outboard fixtures are working again.

Back to the center fixture..
To isolate the problem of one tube not lighting first I reversed the bulbs. Same tube still doesn't light.
Then I reversed the wires at that end and the same tube still doesn't light.
Then I reversed the sockets and the problem moved to the other tube, so I know I need a new socket.

Question still remains, why do these sockets have two wires each for a single pin bulb?
Do I cap off the second wire OR do I twist both wires together?

 

[KenC]

I'm doing the same to some 8' single pin fixtures. Also replacing t12s with t8s as they fail. Anyway, the new ballast do not wire up like the old magnetic versions. But, the correct diagram is on the ballast.

The power in is black to black, white to white. But that's all I remember without going out to the shop to look at a ballast. I do know that there are 5 wires that join, 'cause I got to use some 5 port Wagos that I never thought I'd need! I think all for wires from one end of the fixture and one from the ballast.

Anyway, look at your ballast, the answer should be there!

 

[Scott H in Wheaton]

Yeah, the new electronic ballast has a red wire that goes to both tubes on one end, and two blue wires, 1 for each tube on the other end. That part is plain to understand, I just can't see why the sockets on the end with the blue wires have two wires each coming out of them.

 

[Milton Shaw]

The reason for two wires is that when the bulb is in the socket it completes the circuit and turns the ballast on. If you look in the socket where the end of the bulb goes you will see two contacts, one on each side. The bulb end connects them.

 

[ckadams00]

Don't mean to hijack but my question is so similar I thought I'd add on rather than starting a new thread.

Q: I'd like to upgrade my T12 shop lights (hanging, not hardwired) to T8 - can I just swap out the ballast and use the old fixtures? Seems like a better idea to re-use than buy new fixtures.

It looks like the T8s fit the T12 sockets . . .is this as simple as a ballast change? Anything else I need to know?