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Posted By: BigB Bad Lamps - 05/15/07 03:06 AM
I just had an entire case of bad T-12 40W lamps. I am wondering if it was because I stored them in a hot attic loft for a year. They will faintly glimmer but will not light. Swapping lamps in from other fixtures verifies the fixtures are ok.
Posted By: NORCAL Re: Bad Lamps - 05/15/07 04:13 AM
What brand? I had a case of F30T12/CW GE lamps have 7 out of a case of 24 be DOA.
Posted By: johno12345 Re: Bad Lamps - 05/15/07 09:56 AM
We use Osram lamps and we get at least 1 fail per box. The annoying thing is that if you replace a tube that is out and the replacement doesnt work, you assume the fitting and we call the electrician in.

We are wiser now....

We have had better luck with the GE Polylux XL but maintenance cant get them for some reason.
Posted By: Zapped Re: Bad Lamps - 05/15/07 05:56 PM
Bad lamps are almost always a result of bad handling. During manufaturer, all lamps are tested automatically, and an automated sensor mechanism kicks bad lamps out of the line.

Quality comes into play when a lamp gets kicked around a little. A better made lamp should be able to take a little abuse, and conversely, a cheaply made lamp will fail - usually at a weld junction. I find that the lamps that are better packaged to handle shock and vibration during handling tend to deliver a much lower failure ratio.

Although you can't do anything about the shipping and receiving guys at your supplier, a little bit of care and thought from the end user should give a few less failures.

Good luck in the future!
Posted By: BigB Re: Bad Lamps - 05/16/07 03:26 AM
The lamps were Osrams. I thought I was careful enough with them, but I guess they could have been bumped around. So much for stocking up, from now on I will buy only what I need.

By the way, does anyone else hate working on fluourescent fixtures as much as I do? And the ballasts cost so much it's hard to make much profit without looking like a crook.
Posted By: Zapped Re: Bad Lamps - 05/16/07 02:11 PM
Don't hate fluorescents really. You gotta charge what you gotta charge - we have no control over the rising cost of the steel in the ballasts.

You wanna hate a lamp type? Try changing out 1000 watt Metal Halide ballasts in tennis court lights over your head on a shakey lift 30' or 40' up in a 30-40 MPH wind. Fun!
Posted By: BigB Re: Bad Lamps - 05/18/07 01:22 AM
OK heres an update. Didn't have time to go to the lighting wholesale today so I stopped at HD and grabbed a two pack of lamps, stopped at the customer's house, popped them in and they lit right up.

Then I go home and eat dinner, go out to my shop and look at that bad case of lamps. One by one I try them in my shop light fixture, THEY ALL WORK. I swear they would not light in the customers fixtures, even the ones with new ballasts. But her old lamps worked fine in them. I just can't figure it out, they are all the same type of lamps, it just doesn't make sense. This is why I hate fluourescents.
Posted By: Sixer Re: Bad Lamps - 05/18/07 03:00 AM
I've had the best luck with Philips lamps.

Some of the old fixtures from the 70's are so tight that you almost break the tubes replacing them - most often the ends break.

A little trick that has worked for me in the past is: if a new lamp doesn't work, remove it, turn it end for end and replace it. Don't ask me why, but after doing that the lamps will fire for me 50% of the time.
Posted By: BigB Re: Bad Lamps - 05/18/07 03:48 AM
I'll try that trick next time sixer. Maybe, if the customer is watching, I'll mutter "abra ca dabra" at the same time, after all, most of them must think we are magicians what with some of the places they think we can fish in a wire!
Posted By: johno12345 Re: Bad Lamps - 05/18/07 08:15 AM
I have found too that sometimes a lamp, which is tested ok, wont work in a fitting, even with a new starter. However, if I fit a High Frequency starter, all is well. I cant say that I have tried turning them around, will try that next time.

We are going to start sending the duff ones back, all those £1.50 add up!

It does seem that thee old fittings last the longest. We have some from the late 60's working well but the new ones last about 5 years. It also seems that the starter type fittings last longer than the HF fittings.
Posted By: NORCAL Re: Bad Lamps - 05/18/07 12:09 PM
Starters??? I thought they went out in the middle of the last century.:)
Posted By: Hendrix Re: Bad Lamps - 05/18/07 04:28 PM
Right on!
Posted By: johno12345 Re: Bad Lamps - 05/18/07 07:31 PM
Most over here seem to have starters. We certainly have plenty. All the new fittings are the starter type, even the 2D fittings. I take it that you guys only have the HF type?
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