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Peculiar problem with t12 ballasts...

14259 Views 38 Replies 14 Participants Last post by  ArkAngel06
We own a store that was made some 30 or 40 years ago, and all the fluorescent lighting used magnetic ballasts. They are t12 60w.

Now days they seem to just have the electric ones, so we bought some of them. The wiring is a little different, but we wired them up the way the diagram says. The problem is that only one bulb lights up. The really wierd thing is that if the right bulb lights up, and then you switch the bulbs, the same bulb that originally lit up will light up again on the other side, and the other bulb is out.

So that's probably the bulb that's bad, you say? Nope, we have changed 3 ballasts, and they all do this same exact thing with a myriad of different bulb combinations, most of them being brand new.

The ballasts are for 96"x2 t12 bulbs, and that's what we have. The bulbs are 60w, and the ballast output is 277w. The magnetic ballast output was 750w.

The differences in the magnetic ballast wiring, and the electronic ones are as follows.

Magnetic had 4 wires. 1 white, 1 black, 1 red, and 1 blue. The sockets also had 1 of each color, and the wires just went to the corresponding colors. Red to red, blue to blue, etc.

Electronic ones have 5 wires. 1 white, 1 black, 1 red, and 2 blues. The white goes to white, the black to black, the red to blue+red, and 1 blue goes to black, and 1 blue goes to white.

I am so lost here, please help :huh:
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Post the number on the ballast.
Post the number on the ballast.
Sure, ballast says:

Multi-Volt
ProLine T12
ge260is-mv-n-diy (the I after 260 may be a 1, I really can't tell)
Product code: 74475

That is from a GE brand ballast, we also bought a Phillips brand ballast (that also had the same wiring) that did the same thing.

The bulb numbers are f96t12. 60w.
A warm (excited) lamp will light much easier than a cold one. So if the lamp lights and then you move it, chances are it will light before the cold lamp will. I am am taking an educated guess. So lets perform an experiment.
Mark the lamps and turn off power to the ballast. Remove the lamps and allow them to reach the exact same temperature. Then try reinstalling to see if your problem is the same. To see if it is indeed because the lamp had been warmed up. Check my theory.
Its worth a try.
Are you wiring the new electronic ballasts according to the drawing on the ballast? I have replaced literally hundreds of magnetic with electronic without the issues you describe.
White and black are the power leads. Blue goes to one side of the bulb lamp holder. The red goes to the other side of the bulb lamp holder. Jumper the red to the other lamp holder on the same side of the bulb.

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You probably have ruined the new ballast by putting line voltage on the output side.
Follow 47_47's diagram
A warm (excited) lamp will light much easier than a cold one. So if the lamp lights and then you move it, chances are it will light before the cold lamp will. I am am taking an educated guess. So lets perform an experiment.
Mark the lamps and turn off power to the ballast. Remove the lamps and allow them to reach the exact same temperature. Then try reinstalling to see if your problem is the same. To see if it is indeed because the lamp had been warmed up. Check my theory.
Its worth a try.
Are you wiring the new electronic ballasts according to the drawing on the ballast? I have replaced literally hundreds of magnetic with electronic without the issues you describe.
That is definitely not how it works, as I just unplugged the cold one and immediately plugged it back in and it lit up while the warm one was off. It seems a little random, but it will usually follow the one that initially had the power, but not always.

As for the diagram, yes, I followed the one on the ballast, although there are some differences in the diagram and the sockets. The sockets only have one wire each, while the diagram shows 2 wires for each. However, the colors are going to to the correct places.

Also, for each segment of lighting there is 2 black and 2 white wires. Both blacks carry power, but 1 black and 1 white go straight through while 1 white and 1 black go to 1 socket each. I have tried hooking the ballast up to either black and white with the same result.
That diagram is the same one from the ballast, and that is how I hooked it up. Read my last post to see why the output may have gotten power, but how I really couldn't help it.
Pics of the wiring will help us.
I will take some and upload them when I get home in an hour or so.
Pics of the wiring will help us.
Yeah some pics would get you the right answer faster.
If this place is like one I rented, do not follow the existing colors. Many times they used what ever wires they had when changing a ballast, ignoring colors. As jbfan stated pics would help.
6
Yes, I didn't follow the coloring, I went purely by the diagram.

Here are the pics.






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You have the ballast inputs wired to the outputs. You need the incoming power going to the whites and blacks on one side of the ballast.
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As you can see in the last picture, both black wires are connected at the socket, and one goes to the ballast, and one goes to the next fixture.

The power wires, and the outputs are the same wire. This doesn't make much sense to me, but that's how they were originally wired up.
I see the 2 blue wires wired to the line input connections. The only connectikns to the white and black should be the line voltage. Likely ballasts are toast.
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You have the ballast inputs wired to the outputs. You need the incoming power going to the whites and blacks on one side of the ballast.
Just like Tim says disconnect the blue wires we gotta start doing it right.ok the red wire Is wired correctly the problem lies on the other side whrere the blue wires are supposed to go ...you say there's already a black live wire connected here right? In that case disconnect that wire cap it and c9nnecy one blue wire to each connector also get rid of that jumper across the connectors
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But I wouldn't know where to start with this. Both black wires and both white wires go into a socket on each fixture. You would have to pull those out of the socket, put a new blue wire in each one, and carry the white and black to the ballast. Then how would the next fixture get power? Run a a third wire from the ballast to the next fixture? Do you see the problem here?
Where are the wires that supplied power to this fixture? I can see an empty knockout, but no wires.
I had the same problem a few weeks ago. I understand what ur saying but your are going to have to do some work to make it work.......
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