Problem with fluorescent lamp or ballast


One pair of the fluorescent lamps in the kitchen stopped working. I replaced with the other pair in the same big box on the ceiling. They still didn't work. Then I bought a ballast from Home Depot, a magnetic type, and installed it. One of the two bulbs can flash with dim light. I did this before (in a different place). Replacing ballast and all was well. But this time I'm at a loss.
Can somebody tell me how I check the ballast or circuit? I did all the following measurements. Both ballasts are like this:
_________ Blk | | Blu W | | Blu Y | | R Y |_________| R
Old ballast: Blk to W: 12ohm; Y to Y: <2 ohm Blu to Blu or R to R: <2 ohm; no continuity between Blu and R Blk to Blu: 3ohm; W to Blu: 10ohm
New ballast: Blk to W: 8ohm; Y to Y: no continuity Blu to Blu or R to R or : no continuity Blk to one Blu: 1.5ohm; Blk to the other Blu: no continuity W to the first Blu: 8ohm; W to the other Blu: no continuity
After I turned power on, I checked the voltage on the wires when the new ballast is installed: Blk: 120v; Y and W: 0 Blu: 120v; one R: 0; the other R: 140v
Of all the 4 sockets (for 2 bulbs), one which 2 blue wires go in has 120V. The other 3 are 0.
I don't know what I should measure exactly. Thanks for help.
Yong Huang
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Before you changed the ballast you should have checked the bulb contacts for corrosion. I had a fixture driving me nuts and finally decided to abraid the contacts by removing and replacing the bulbs about 20 times. That was 2 years ago and the fixture has been working great since.
By the way a tip for anyone with flourscent fixtures in the garage. This has been posted before but a long time ago. If your area suffers from cold weather and bulbs don't work well in winter, by those cheap flourscent tube protectors. They help the bulbs warm up much faster and the bulbs will be bright even in a cold winter.

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Do the tubes light up when you brush a hand over them? Check your ground. Tubes must be within 1/2" of a grounded metal surface (the chassis) or they won't start.
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One of the tubes will show dim flickering light if I rub on it. The other one still doesn't work.
To Art, I even moved the other known good tubes into these two sockets. They still don't work. I checked the inside of the sockets. I didn't see rust or anything. Thanks.
Yong
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Yong Huang wrote:

Did you check the groundiung of the fixture or not? Those lamps are cheap, why not try a pair of brand new one. Also there are older 40W lamps and newer power miser 37W ones. They act different.
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Wrap a grounded wire around the tube (watch the end so it doesn't short out a terminal pin). Tube should light up with no problems.
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This is a follow-up to my question. I solved the problem by finding out how dumb I was. The two red wires on the ballast are supposed to each connect to each of the two red wires in the box (I mean the box that has the lamp sockets). But instead I accidentally connected the two red wires on the ballast to themselves, and did the same to the two red on the box. No wonder the socket the two red wires go in didn't have power. It's embarrassing to admit it. But people in this newsgroup seem quite friendly so I thouhght it a good idea to post a follow-up. Thanks everyone.
Yong Huang
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