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jonezart
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Replacing Florescent Ballast, One Too Many Wires
I have a 2-bulb florescent fixture that needs the ballast replaced. The old one was very big and heavy and had one each black, white, red & blue wires. The new one has one each black, white & red wires but it has TWO blue wires. I'm really not sure how to wire this.
The guy at Lowe's said "just follow the diagram", but I'm still confused, as the fixture itself has only one blue wire. The diagram says I should attach a blue wire to each of the bulb posts, but I don't see where/how. The fixture has one red and one blue wire.
Also, this fixture is not hard-wired into the ceiling, it's got a cord attached. I'm wondering if it would be easier to just buy a new fixture (with the ballast already attached) and just add a cord. The Lowe's guy acted like that would be more difficult, but I don't see how. He was pretty impatient with me and ran off to do something else.
Finally, the box for the new part says it replaces R-2E75-S-TP, but the old part is R-2E75-S-3-TP. What is that missing "3", do I have the wrong part? AND also, the diagram for the new part shows a 4 bulb fixture, while mine is a 2 bulb fixture. Is that an issue?
I'll be looking online for answers, but hoping you guys can help.
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Thanks. I told the guy at Lowe's that I had only 2 bulbs. He told me this is the way they are making them now, to make them energy efficient. Maybe he didn't know what he was talking about and that's why he was impatient with me? I think maybe I'll try another store and see if they can help.
What about my other question re: just wiring a cord into a new fixture? That seems pretty straightforward to me.
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Tolyn Ironhand
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IF your fixture is quite old you may be better off buying a new one. The newer T-8 fixtures are more energy efficient, give more light and light faster. A new fixture would likely be only about $10 more than the replacement ballast.
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Thanks Tolyn. I don't know how old it it is, but old enough to have that old style ballast in it, but it's possible the previous owner put that in himself.
How easy is it to wire a cord onto a new fixture? It looks simple to me, 2 wires and a ground? I can just take the cord off the old fixture.
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Tolyn Ironhand
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Originally Posted by jonezart
How easy is it to wire a cord onto a new fixture? It looks simple to me, 2 wires and a ground? I can just take the cord off the old fixture.
It is pretty easy. Make sure you install a connector where the cord enters the fixture. (A 1/2" NM connector works well) Wire it black to black, White to white, Ground to the steel of the fixture.
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in case anyone is interested, here is my resolution to the problem. I took the fixture apart and found that I would have needed to replace the tombstones anyway because one was partly melted or something. It was not right. Also, I went to Home Depot and found a ballast for about $15 cheaper. Same thing as the last one but another brand. Also, the diagram was easier to read and it said right on it "cap off unused wire". So from what I could tell, the ballast could power one or two bulbs. I would have had to run the red wire to the other end where the main power was wired. On pulling out the tombstones I could not see where the red wire would have fit as all the spaces were taken. Another reason to think about new fixtures. I found a local electrical supply store and a bunch of electricians happened to be there. They eventually sold me a new fixture, it's 8 ft but uses four 4 ft. bulbs.
I was able to wire the power cord myself. At 6 feet it's too short, though and doesn't reach the outlet because the place to ground was in the middle of the fixture instead of at the end like the last one. I only have 2 extension cords handy, a really long one and one that's being used by the other fixture. When I plugged it into the really long one the light in the bulbs seemed to roll (if that makes sense), but the shorter cord didn't seem to produce that. Is that normal? Is it because of the length the current has to travel?
Other than that, the only problem seems to be that the spectrum is not right. But the bulbs were cheap and I can live with it for awhile.
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Thanks, pcboss. Is it always necessary to put the ground wire in the spot that says "GRND"? I noticed that there were some bumps to help hold the wire in place, but the screw hole goes through the fixture and comes out the other side like all the other holes. Could I actually move it to another spot to lengthen my cord?
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ray2047
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I noticed that there were some bumps to help hold the wire in place, but the screw hole goes through the fixture and comes out the other side like all the other holes. Could I actually move it to another spot to lengthen my cord
The ground screw must go into a hole with 6-32 machine screw threads. If the holes are small enough and aren't threaded you could use a self threading ground screw. Or you can wire nut a short length of green or bare wire to the cord's ground wire.
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thanks ray. I think I'll just leave it the way it is and get a short extension cord. I don't really feel like messing around with it any more.
Thanks for the help, everyone.
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Tolyn Ironhand
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Originally Posted by ray2047
The ground screw must go into a hole with 6-32 machine screw threads.
Just an FYI: Green ground screws are 10-32 threads.
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ray2047
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Originally Posted by Tolyn Ironhand
Just an FYI: Green ground screws are 10-32 threads.
Dang! Going to have to type that a hundred times so I remember. Seriously correction appreciated.
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A few weeks later and everything is great. I love the new fixture and if I hadn't bought four 8 foot bulbs and now have two extras, I'd be replacing the other fixture as well.
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There is a solution
I have the old single pole T12 96 inch fluorescent fixtures and have had to replace 2 of the old ballasts with the new electronic ballasts with the "extra" blue wire. One was replaced over a year ago and is working perfectly. The other I just did, and it is working perfectly also. The solution is as follows: First, turn off the power supply to the fixture. Disconnect the AC power wires from the 2 black and 2 white fluorescent fixture wires. The black and white wires from the ballast must then be wired directly to the AC power wires. The RED wire from the ballast is then wired to the 2 black and 2 white wires that feed the 2 flourescent tubes. Now at the other end of the fixture you have a blue and red wire which need attention. Connect the blue wire to one of the blue wires coming from the ballast; it does not matter which blue ballast wire you choose. Then connect the red wire to the remaining blue ballast wire. I hope this is clear to you.
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