Timely topic.
My garage has T8's and in the past 4 years, 16 of the 24 have died and/or have reduced output. I need to fix this.
Short of moving a good light into a former bad/unlit location is there anyway to check a ballast for failure and vise versa the tube? Not real keen on playing easter egg hunt on this given the **** in the way and ladders and all.
Some of the failed/failing tubes have a black ring near the metal end which I understand is the classic tell-tale of a failed bulb. Others have an orangeish hue (no black ring) and never go full bright.
I installed these T8's maybe 5 years ago, homeowner grade T8 unit's from Lowe's. Not sure of fixture brand or ballast within. The bulbs are Phillips units with supposedly 24,000 hours on instant start ballast and 30,000 hours on programmed start ballasts. Garage lights are turned on maybe 2-3 times a day for maybe 4 hours total.
Since I'm in the need to shop for bulbs, figured now is the time to ask.
If I'm reading this correctly, you installed these lamps 5 years ago and only use them 1200 hours per year. 4 years ago, they started dying and now only 8 are still on. You sure didn't get your money's worth.
There's lots of questions in your post. Before I answer them, I'll make some assumptions... 1) you have standard instant start ballasts 2) everything is wired correctly and grounded properly 3) everything is in good physical condition. 4) you have 2 lamp fixtures
Its difficult to accurately check an electronic ballast for correct operation, so you have to look for clues to see if it's working. If you have a fixture with one lamp on and one lamp out...the ballast is good and the lamp is dead. If your fixture has two lamps out, it could either be the ballast or both lamps are dead or all 3. A simple way to check is to put one known good lamp in. If it fires, the ballast is good.
The black ring is tungsten from the cathode and is an indication that the lamp has been turned on/off numerous times, or that it was poorly made. You see this alot on lamps that are on occupancy sensors or where ever the lights are turned on/off alot..like lavatories. Black rings are not necessarily indicative of a failed lamp. Under the circumstances that you described, you should not have lamp failures yet, nor should you have black ends. Something isn't right about this.
Orange or pink lamps have lower than normal gas pressure inside. Either there was a small leak or they weren't properly dosed during manufacture.
Here's my recommendation...
It sounds like you have an issue somewhere. I'm guessing cheap ballasts plus bad lamps. You can try to find it and troubleshoot it, but a better use of that time would be to just bypass the ballasts and put new LED tubes in there. ... or new fixtures.
Good luck,
CD
