T5 Light problems

[nhman]

Anyone have any experience and or suggestions for the following issue with T5 bulbs not turning on in the AM that I am recently experiencing:

The setup:
- Basement setup, no windows. Constructed with concrete board and sealed for house protection from humidity.
- T5 HO bulbs in a 4 foot, 8 bulb New Wave fixture.
- I have 6 banks of these fixtures hung above the growing benches at variable heights, per orchid height and leaf top foot-candle measurements by a good light meter. All are on timers, total "day" varies thru the year.
- There are several fans for circulation: Two 8 inch greenhouse fans are above the lights, there are also two fans that rotate to circulate air at the plant level.
- Humidity is controlled by a Humidistat and Hydrofogger using RO water: Humidity kept at 50% during the day, rises to 70% at evening with the lights and air conditioner off.
- The heat generated by the lights are moderated by an air conditioner set to keep go on at 72 degrees and keeps the temperature in the 65 (nights) to 80 degree (days) range.

Problem:

I have had numerous banks of lights that are NOT turning on in the AM. If I restart them or rotate the bulbs, they go on. I have tried new bulbs - no change.
The only thing that seems to have helped is to let the humidity decrease to about 40%, so I'm wondering if this bulb thing is humidity related?

Any ideas or suggestions are welcomed!

I am getting to the point of looking at the newer LED systems or at water cooled system if I can't solve this issue as this is rather labor intensive in the AM and I can't assure lights when I'm not at home on vacation.

Thanks in advance for any ideas, suggestions, direction,etc, etc, etc.

[Ross]

Humidity shouldn't be an issue in a normal basement. I don't get that problem myself. I'd suspect one of more fixtures as the culprit (but even that's unlikely). Have you had your voltage checked with a meter? An electrician can read the current under load and see if you are getting low voltage. LED systems are not nearly as bright and the technology is not nearly there yet. You say you have 6 banks of 4 tubes. Each fixture draws over 200 watts. 6 of these will draw almost 1300 watts. Unless they are on a circuit all by themselves, you are probably overloading a cicuit and the weak voltage may be keeping the fixtures from starting. Try splitting them up across different circuits and having the start times vary by a few minutes to be sure there are not more than a couple doing the initial burn-in when they first come on. Also, try setting up no more than two fixtures on each timer.

[nhman]

Ross,

Thanks!

I actually DO have each 8 bulb 4 foot bulb fixture on separate circuits and individual times already.
This was set up at the design of the room and the wiring of it to try and avoid just this type of issue and i have had an electrician measure the electrical consumption - with the addition of GFC's on every outlet, and outside of the comment that I would do well with my own nuclear powered generator to power them all, everything seemed to be OK and not overloaded.
The fixtures also do come on at intervals over about 1 hour in the AM as well.
Any other suggestions????

[Ross]

Not really. I have a single tube t12 shop light in another part of my basement that does same thing in the summer when humidity is high. If humidity were the culprit, then why wouldn't this be a more common problem amongst board members? There are others here also growing under lights in a basement and I haven't heard this problem expressed before. I think there is some issue with your setup that we haven't discovered. Have you discussed this with the electrician? It doesn't sound like the problem is the fixtures or tubes. If that were so, then switching tubes and/or restarting them wouldn't work either. Ask your electrical company if they'll temporarily install a recording device on your meter. They have a device that goes between the meter and the base that samples voltage in decimal volts several times a second over a 7 day period and records this info. They can pick up actual loads in volts over 24 hours for 7 days and show you actual voltages as the lights come on. Those fixtures (I use a 8 tube New Wave myself) take more power to start the tubes than to run them. The tubes need to heat up before they glow steady and voltage varies during this period. Perhaps your service (or a leg of your service) isn't keeping up? I have a 200 amp service (new) and I still get fluctuations for certain appliances at certain times. It must be frustrating, but don't give up. LED just won't give you the lumens you are after. You'd be better-served with a MH hot light on a mover.

[nhman]

Ross,

Thanks!
I will begin acting upon your suggestions and get my friendly neighborhood electrician out after the holidays to begin the evaluation.
Tis strange tho', as only two fixtures are always a problem and two are sometimes a problem. That leaves about 4 that are behaving well and not problematic at all.
I'll let you know if I find a solution or at least can terminate the problem without redoing my lights.
Have you had any experience with the water cooled lights? This is interesting, as it may solve both light and heat problems - but they are fixed and not able to be easily mounted for movement due to the water tubing used for the cooling.
Anyway, before spending any more $ on this, I will hope to resolve the problem with a little detective like investigation based upon all of your helpful information.
Thanks again Ross!

[flhiker]

I do a lot of electrical work and have a questions about your problem. Do the same lights have the problem or does it happen to different lights at different time's? If it is the same light each time it is definitely the ballast. It is not uncommon for a bad ballast to work intermittently. The built in starters can go bad. The old days florescent lighting had external starters and were less expensive to change then the ballast. There's really only 3 things that can be wrong with a florescent light fixture, ballast, bulbs or broken contacts. Since you changed the bulbs and didn't see any broken contacts it must be the ballast. But if it is random I would get non-conductive grease and put a small amount of at the contact points of the bulb. Just in case the moisture is causing corrosion. Florescent lighting can be a pain in the ass. I don't think it is a voltage problem. If it was a voltage problem, they would turn on once the proper voltage returned. Also you would see power fluctuation in at least half of the house. good luck

p.s. Did you check your connections to the lights and at the timers?

[Ray]

Originally Posted by nhman

Tis strange tho', as only two fixtures are always a problem and two are sometimes a problem. That leaves about 4 that are behaving well and not problematic at all.

That makes me go back to Ross' original voltage suggestion.

In what order are those set to come on? If it is voltage related, I would expect to see the 4 good ones come on first, the "iffy" ones next, and the "no-way" ones last. You might try swapping the order to test.

You stated they were on 8 different different circuits, but is that 8 separate breakers on the panel? Even plugged into 8 separate wall outlets does not necessarily mean separate circuits.

[flhiker]

Somehow I missed the info on which ones where working and not working.

Definitely a Ballast problem. If it was a voltage problem they all would be affected. If I'm understanding you correctly you have one fixture with 8 bulbs.- T5 HO bulbs in a 4 foot, 8 bulb New Wave fixture. which means one source of power for all bulbs. Most likely when you remove the cover there will be 4 ballast one for every 2 bulbs but it can have 2 ballast for 4 bulbs but hearing your problem I think its has 4 ballast. After repairing and replace hundreds of florescent lighting fixtures over the years, I willing to bet it's the ballast.

[nhman]

The fixture seems to be a one ballast for two bulbs type.
I have made several changes:

I have reduced the humidity during the day to 45% and at night to 60%.

I have separated the lights to different timers and staggered the start times.

I mis-spoke earlier: I actually have four circuits for the growing room with three circuits dedicated to the lights - two fixtures per circuit via two separate GFI outlets. The other circuit and outlets power the air conditioner and the fans.

I will try this work around first to see if there is any change/difference. This MAY work, as when I took a light fixture that was NOT a problem and placed it in position of one that WAS a problem - it had the same issue. So.......

All of the lights were bought at different times (the every expanding collection ya know!) and the age of the fixtures does not seem to matter.

Thanks to all for the suggestions and I will keep all updated over the next few days to see if I've solved the problem!

[nhman]

OK: At an n= 3 days experience, I am willing to agree that it must be a ballast problem. You were spot on Flhiker!!!
Even changing the timing of the two most problematic fixtures, I still am having problems. Sometimes rotating the bulbs (after the fixtures are warm) will get some of the lights to go on.
Decreasing the Humidity has helped somewhat, but not enough.
Therefore, I am going to change out the ballasts - or at least try to - not being an electrically inclined type, but one that CAN follow instructions well (I know, turn the power off before doing anything...)- I have hope.
And failing that, I can always talk my wife into letting me spring for another 2 new fixtures.........
Thanks for all of the help and support!!!!