First the question – Is there a way to test a flourescent tube? I usually just try it in a known functioning fixture. The reason I ask is that I just replaced a single 4ft strip fixture that I thought was defective since it stopped working and when I installed a new tube (from HD) it still did not work. Therefore the fixture must be bad (ballast I assumed), after much cursing – it was buried under pipes and cables in a joist bay in my laundry room – I got the new fixture in place, installed the new tube and WTF it still did not work. I took that tube installed it in another fixture and it was still dead. I took the tube from that fixture installed it in the new strip and it worked. Sure enough when I installed it in the recently removed fixture it worked. So it was the tube and not the fixture.
So, to alleviate future stupidity, is there a way to check the tube when it is out of the fixture? Since there is no direct connection between the contacts I assume a continuity tester won’t work like it would with an incandescent bulb.
Thanks.
Replies
Hi Chris, we use a commercial lamp tester, it has an antenna that you touch to the lamp and the lamp ends will glow. We use it for tubes and High Intensity lamps, I dont remember what we paid for it, but it wasn't cheap, its not the kind of tester a home owner would bother to buy. Another choice is to take the lamp outside near high voltage transmission lines!!! I told my buddy about this (he lives right next to the towers) he thought I was full of it till we pulled an 8' lamp out of his workshop and walked out into his backyard. When he saw it start to glow he almost dropped it!! This year he built a 28 x 28 garage and had it wrapped with vinyl siding and aluminum trim, the siders got nervous because they could feel little static shocks when they were handling the aluminum trim, it was pretty freaky.
"Another choice is to take the lamp outside near high voltage transmission lines!!!"That really doesn't mean anything about how they will work in a fixture.Now if these are T12 bipin bulbs then there is a filament in each end and a continuity test would be meaningfull. But there could also be a problem with the gas charge and that would need special testing to determine.BTW, I once picked up a package of 6 clear bulbs and when I went to install them they all had broken filaments. Did not appear to be from shock. My guess is there was a batch of bad wire that has "slag" embeded in it.
So I guess the best bet is just to try the new tubes in a known good fixture. Now I just need to make sure I have known good fixture.
Thanks for the help.
don't feel bad,i had same thing happen,light don't work so i put in 2 new bulbs,still don't work so i buy a ballast and put it in nothing. now i'm p.o. so i go buy a new fixture, still nothing. tried different bulbs,let there be light. almost a whole day because of this.i probably made about 50 cents a hour that day. larry
hand me the chainsaw, i need to trim the casing just a hair.
I know how that goes. I have four lights out in my shop so I thought I would replace them one at a time as money allowed. Bought the first one and put it in..nothing. Checked the circuit and checked out ok 110 v. I was looking over the light wondering why it wouldn't work. Then it caught my eye. I read the tag on the ballast... 220v.. no wonder it wouldn't work it was getting half the voltage it needed. I had thought that a 220 bulb had only one plug at each end instead of two. But this one had two at each end. I didn't take it back because I do have other areas of the shop that are 220.
DaneI will always be a beginner as I am always learning.
take the bulbs and walk under a high power supply line. The type that 100 feet up. If the bulb start glowing they are good.
I know about that little trick.
A handicap friend of mine was a ham radio operator. He showed me how to us a florescent bulb (small one) to find stray RF in his Henry linear amplifier. Was as little spooky at first seeing it light up with no wires to it.
DaneI will always be a beginner as I am always learning.
Flourescent bulbs don't come in voltages.You change the ballast, not the bulb.
Very true.
I also found out that it is only another $5 to buy the whole fixture instead of just the ballast and bulbs.
DaneI will always be a beginner as I am always learning.
Chris,
That brings up an interesting point.. I sold lite bulbs during one point in my life, you learn amazing things on the inside of any industry,,
For example florecent lite bulbs may lite up but they gradually lose their effectiveness, producing fewer and fewer lumens per watt used..
Differant bulbs even from differant manfactures produce differant levels of Lumens..they vary due to differant levels and quailties of the ingrediants in the bulb.. Most Hardware store bulbs are poor performers compared to some sold by some industrial supply houses..
The color of lite produced vary from cool white to warm and there are actually bulbs available that produce true color.
Too much to list here but there is a lot to know about those other than what size do you need....
It's funny but I usually buy tubes by the case from Grainger and have never had a problem. This tube was from Home Depot but it was a Phillips brand so I guess the urban legend about different quality items being sold at different outlets may be true.
Don't feel rained on CHRIS.
We buy cases of 5 year warrenty bulbs form a lighting supply company, much like what frenchy probably worked for. These are true color bulbs, and even with our volume discount we pay over $5.00 each (retail is over $11.00). We get bad bulbs on a regular basis. It happens in every manufacturer, and every supplier we have ever used.
For us rolling bulbs around in a multi-tube fixture is SOP when one doesn't fire. Swapping out for another out of a case is also SOP, before we cgange ballist. In a four story, block long office complex, that is a lot of bulbs.
Dave