Florescent lighting problem

[Greg1707]

I have little experience with florescent light fixtures so maybe you guys can help. I was called to a bakery with several florescent light fixtures that are not working. There are about 10 fixtures in a row all on the same circuit. The first five work and the second do not. I did not have much time on my first visit so I checked the first non functioning fixture to see if it was receiving current, it was. I also swapped a couple of tubes to make sure that was not the problem.
Does anyone have an idea of what may be the problem? These are older troffer type fixtures.

 

[readydave8]

I have little experience with florescent light fixtures so maybe you guys can help. I was called to a bakery with several florescent light fixtures that are not working. There are about 10 fixtures in a row all on the same circuit. The first five work and the second do not. I did not have much time on my first visit so I checked the first non functioning fixture to see if it was receiving current, it was. I also swapped a couple of tubes to make sure that was not the problem.
Does anyone have an idea of what may be the problem? These are older troffer type fixtures.

I would check again for current with anything that puts a load, maybe pigtail with 100w lamp (bulb), if it lites just fix all 5 fixtures one at a time, if baker asks why all 5 failed when other set of 5 still worked, tell him it was due to harmonic symetry.

 

[Little Bill]

I have little experience with florescent light fixtures so maybe you guys can help. I was called to a bakery with several florescent light fixtures that are not working. There are about 10 fixtures in a row all on the same circuit. The first five work and the second do not. I did not have much time on my first visit so I checked the first non functioning fixture to see if it was receiving current, it was. I also swapped a couple of tubes to make sure that was not the problem.
Does anyone have an idea of what may be the problem? These are older troffer type fixtures.

I would first ask the owner if something has happened or changed since they were all working. Maybe someone adding a circuit or even being in the circuitry for any reason. Also find out when they stopped working. One or Two could have been out for a long time and he's just noticing when another one died.
Other than that, what ReadyDave said.

 

[jeremysterling]

Here's how I do it:

I use my tic tracer (non-contact tester) to see if there is voltage present at a socket (tombstone). This suggests that the ballast is good and has power to it.

If the tic tracer lights up, try new bulbs. If new bulbs do not work, replace the ballast. Done.

If the tic tracer does not light up, pull the belly pan and check the line with tic tracer. If tic tracer lights up, replace the ballast. Done.

If the tic tracer does not light up on the line conductor and the light switch is on, pop some tiles, get the real voltmeter and troubleshoot the circuit.

From experience, I would start out assuming you have five bad ballast.

 

[stevebea]

Has anyone tried the Milwaukee flourscent lighting tester?

 

[Greg1707]

replace ballast?

replace ballast?

Thanks for the suggestions. The troffers are old and nasty looking. I think it would be best to replace the entire fixture rather than dealing with replacing ballasts?

 

[tdexxx]

Could it be a problem with the neutral at the fifth light?

Tom

 

[grady180]

Are they daisy chained together? Are the 5 not working at the end of the circuit? If so, I'd say loose connection at the last working light. I like the idea that somebody posted about checking the tombstone sockets with a tracer. That works good for troubleshooting. I doubt all 5 ballast are bad unless the muffin man has been putting this issue off for a long time.

 

[readydave8]

Are they daisy chained together? Are the 5 not working at the end of the circuit? If so, I'd say loose connection at the last working light. I like the idea that somebody posted about checking the tombstone sockets with a tracer. That works good for troubleshooting. I doubt all 5 ballast are bad unless the muffin man has been putting this issue off for a long time.

I also thought unlikely that all 5 ballasts were bad but I see it all the time, usually as others have said they don't notice or don't bother calling as they fail, call comes when the last 1 or 2 have failed.

Hope OP will let us know the answer.

 

[jeremysterling]

Thanks for the suggestions. The troffers are old and nasty looking. I think it would be best to replace the entire fixture rather than dealing with replacing ballasts?

It is so much easier and cheaper to replace the ballast. If it is T12, convert to T8. If it is T8 rapid start, convert it to T8 instant start. The drawback is the five that are still working will require the customer to have different lamp sizes for replacements.

If the lens is nasty, home depot sells replacements. While the lens frame is off, paint it with gloss white. I've seen reflector kits too, but that is overkill, IMO.

If the fixture is completely rusted out or a new grid ceiling is going in, then it is time to consider replacing the whole troffer. Installing a replacement luminaire brings in the possibility of new wiring method, new cabling, new support wires, new grid pieces...replacing the ballast is much easier.

 

[Electric-Light]

Are they daisy chained together? Are the 5 not working at the end of the circuit? If so, I'd say loose connection at the last working light. I like the idea that somebody posted about checking the tombstone sockets with a tracer. That works good for troubleshooting. I doubt all 5 ballast are bad unless the muffin man has been putting this issue off for a long time.

I second this.

Good chance a loose wire nut connecting the two sections together let loose and cut out that part from the circuit.

 

[handy10]

I just replaced two ballasts. Here is the situation. There were two 4' 4 bulb T8 fixtures on the same circuit, but not daisy chained. None of the eight tubes lit; in fact, none even glowed. The homeowner had replaced one tube which did not glow either. The fixtures are probably five years old. I checked that power was coming to the ballasts. When I replaced one ballast, only one tube in the fixture lighted; that was the tube the homeowner replaced. I replaced the other tubes, all of which appeared to be good, and the whole fixture worked. I repeated the process for the second fixture.

So here is the question: how do eight tubes and two ballasts all go out. I think the answer is Lightening caused the problem. We had a sever storm ten days ago in our area.

 

[LEO2854]

I have little experience with florescent light fixtures so maybe you guys can help. I was called to a bakery with several florescent light fixtures that are not working. There are about 10 fixtures in a row all on the same circuit. The first five work and the second do not. I did not have much time on my first visit so I checked the first non functioning fixture to see if it was receiving current, it was. I also swapped a couple of tubes to make sure that was not the problem.
Does anyone have an idea of what may be the problem? These are older troffer type fixtures.

If you install new lamps and they do not light then the ballast is bad so just change both the ballasts and the lamps.

 

[Electric-Light]

I just replaced two ballasts. Here is the situation. There were two 4' 4 bulb T8 fixtures on the same circuit, but not daisy chained. None of the eight tubes lit; in fact, none even glowed. The homeowner had replaced one tube which did not glow either. The fixtures are probably five years old. I checked that power was coming to the ballasts. When I replaced one ballast, only one tube in the fixture lighted; that was the tube the homeowner replaced. I replaced the other tubes, all of which appeared to be good, and the whole fixture worked. I repeated the process for the second fixture.

So here is the question: how do eight tubes and two ballasts all go out. I think the answer is Lightening caused the problem. We had a sever storm ten days ago in our area.

Was it cheap no name ballast? They just fail out of the blue sometimes. It happens even to the name brand ones, but more so on cheaper ones where they're not held to same quality check.

 

[readydave8]

I have little experience with florescent light fixtures so maybe you guys can help. I was called to a bakery with several florescent light fixtures that are not working. There are about 10 fixtures in a row all on the same circuit. The first five work and the second do not. I did not have much time on my first visit so I checked the first non functioning fixture to see if it was receiving current, it was. I also swapped a couple of tubes to make sure that was not the problem.
Does anyone have an idea of what may be the problem? These are older troffer type fixtures.

So did you find out what the problem was?