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#68144 - 07/29/06 05:13 PM Flourescent Lighting  
GA76JW  Offline
Joined: Mar 2004
Posts: 193
Suwanee, GA USA
The major components of a flourescent light are basically the lamps themselves, the wire, the ballast and the sockets.

Now that we have that out of the way. I have a light in the kitchen that flickers for a few seconds before it finally comes on. When it comes on it works fine and stays working so the lamps are fine. The wire must be fine or else it wouldn't work either.

I have adjusted the lamps in the

Now leaves the questions:

Is the ballast going bad to make it flicker?

Has anyone else had this problem or encountered anything similar?

Or does everyone just trash thier old lights and buy new?



"If common sense was common, everyone would have it"-not sure, someone here

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#68145 - 07/29/06 05:52 PM Re: Flourescent Lighting  
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
Lights are often replaced, simply because the fixture often cost less than a replacement ballast.. and you eliminate all the variables.

Let me explain a bit about how a fluorescent light works. You turn a switch "on," the ballast transforms and saves up the electricity, makes a big spark inside the bulb, and the gas in the tube glows as a result. (Greatly over-simplified!!)

Notice the parts about "saving up electricity" and "making a spark" Lots of things can interfere with those happening.

Even a poor connection can have the effect of making it harder for the fixture to get enough power to make a spark powerful enough to light up the glass.
So can a loose bulb, a bad bulb, bad socket (tombstone), or iffy components in the ballast.

So, in troubleshooting fluorescent lights, the first thing to do is to replace the bulbs with ones that you know are good. It's easiest to swap them between fixtures; if the problem moves, then it's in the bulbs.
Then check your connections. Take off the wire nuts and look to see if there is lots of good copper to copper contact.
Check your supply voltage.
Check the switch- if all the lights arehaving probs (easy to forget if there's only one light on the switch!)

When you changed the bulbs, you got some idea as to the condition of the sockets.

Now- look at the wiring. IS THERE A GOOD GROUND? Electronic ballasts need a good ground to work properly.
Is the ballast wired in correctly? Easy to get wrong- especially with the 'slimline' types.

You've now ruled out everything except the ballast.... so your problem must be there!

#68146 - 07/29/06 07:59 PM Re: Flourescent Lighting  
LarryC  Offline
Joined: Jul 2004
Posts: 783
Winchester, NH, US
IS THERE A GOOD GROUND? Electronic ballasts need a good ground to work properly.

Having a good ground also includes having the sheet metal next to the bulbs being grounded too. Usually the fine print on the ballast states bulbs must be mounted within 1/2" of grounded reflector.

Also make sure the bulbs you are using match the ballast. Especially using T-12 bulbs with T-8 only ballasts.

edit to delete UBB code.

[This message has been edited by LarryC (edited 07-29-2006).]

#68147 - 07/29/06 09:29 PM Re: Flourescent Lighting  
GA76JW  Offline
Joined: Mar 2004
Posts: 193
Suwanee, GA USA
Well I opened it up and there is no ground. It is part of the old house that still has the old Cloth covered wire in it.

I then checked the voltage and it is 116.8 Volts. It is an older Ballast with T-12 lamps.

There is a receptacle close by that I could pull a ground off of. It is connected back at the panel and goes out the what appears to be a newer ground rod. I know sometime before we moved in 2 years they added some circuits in the house.

"If common sense was common, everyone would have it"-not sure, someone here

#68148 - 07/29/06 09:32 PM Re: Flourescent Lighting  
LK  Offline
Joined: Jan 2003
Posts: 1,429
New Jersey
On customer trouble calls 90% of the time they have the wrong lamps, and yes, a flicker start, or no start.

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