In my shop are six double 40 watt fluorescent fixtures all controlled through one switch. When I turn them on, whether or not any one fixture lights up is purely random chance. For instance, numbers 1 and 4 may work, while the rest stay dark. I flick the switch off and on and this time 2, 4, and 5 work. Another flick and 1,2,5, and 6 work. Sometimes none of them do.
So I stand there playing with the switch until I get enough light to use the machine I need.
I know I could replace them all, and I may, but I’d like to know what principle is at work here. Surely somebody truly understands how fluorescent lamps work. Help!
Replies
replace the bulbs that are black on one end...
sign that the heaters are out of wack...
and spin the bulbs a bunch in their sockets to clean the contacts on each fixture...
some still won't work...
change the ballast or fixture...
yur choice....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
Since you're in the sunny Southland..
When i had CHEAP fluorescent fixtures and my shop got too warm, some of them would just go out, then come on randomly later in the afternoon as the temps cooled.
Get some good lighting. You'll love it.
I wonder if it is the heat or the humidity.My AC has been out this summer.And have been having problem with both the kitchen and sink lights on the humid days.Of course there has been 25 + years of buildup of "cooking dirt" around those fixtures.Have not had problem the office or garage which have been as hot or hotter than the kitchen..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
My lights only ever went on strike when they got over-hot in summer, a time when our humidity is in the single digits. They were dirty ALL the time in my shop, so that didn't seem to make the difference. That and the humming made it compulsory to sink a few hundred dollars into decent HO lighting strips, though, when i put together the new shop. Splinterprune
IMERC is leading you right--from what you are describing, it's bad (or about to be bad) ballasts (or starters for the ballasts, if your fixtures use them).
So, the "bad news" is that you likely need to take and open all the fixtures right up, and take all the lamps out. Start with that first fixture and new lamps (might as well buy new), and then flip the switch. You get a hum, then that ballast probably need replacing. So, you will likely make eleventy trips up and down the ladder for each fixture. (And not get a blame thing done other than futz with the light fixtures.)
Good news is that it's probably not going to be horribily expensive, other than in time.
bought a ballast lately???
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
bought a ballast lately???
Heh. Had a shoplight (double tubes, 48 inches) with a bad ballast about seven years or so ago, went to the blue borg and discovered that a new fixture was cheaper than a replacement ballast.
Don't even want to think what they are now.
Leon
just for grins and gigles turn them on,the ones that don't light ,walk over and touch them with your hand.if they light you need new bulbs. i have no idea what this does but i used to have shop lights that would do this. larry
hand me the chainsaw, i need to trim the casing just a hair.
Are the fixtures grounded? Is it cold in your shop?
This is clearly a case of the shop gremlins becoming bored and putzing about with the electron pixies.
If they keep it up, eventually they'll harass some of those poor little electron pixies to death. And then you'll never get any light in your shop. The rest of the pixies will go into hiding.
Start the tablesaw up, and pass your hand too near the blade, and watch how quickly all those lights come on. That's because the gremlins were distracted by your actions.
What you need to do is to hire all your gremlins out to someone like Haliburton, so they don't just hang around and get bored.
Don't forget the simple things: maybe the switch is tired out. Is it a 49-cent hardware-store special?
Could be a grounding problem also, in addition to the other things mentioned (well OK, Dan already mentioned grounding).
How long has this been happening?
Ed