Need help with lights

[valiko]

So I had a 24" work light over my aquarium for about 2 years.

Now, I've got an aquarium hood, so I took apart the fixture, took out the ballast and wired it to the hood with the same two tubes.


Now the problem is, that when I turn on the lights, they don't work.
They are both dimmed, and if I touch of the tubes they both light up and everythingf is fine, till next morning.


What is going on?I thought the tubes are old, I bought 2 new ones, the problem is still the same

[charlie]

I`m not a electrican , but i think you need to ground the ballast.
Regards

[valiko]

umm, I do not think so. It was not grounded before and it was working.

[charlie]

If it is a shop light fixture with three wires, it was grounded.
Regards

[BigDaddy]

Just to clarify:

You took all the parts out of your existing work light, and mounted them inside your hood?

What material is the hood made from?

If there is any metal.. it should definitely be grounded.  Otherwise, if you are dealing with wood or plastic with no metal reflectors, your fine not grounding it out.

[Marx]

most like fixtures are grounded..

especially near water...

[valiko]

Yes, I took everything out from the work light, and wired it into the hood, except for the ballast, which is outside of the hood for obvious reasons.


And no, the work light was not grounded, the ground wire going to the ballast was connected to anything.

- my light timer does not accept the electric plug with the ground
-  light fixture was on top of the aquarium w/o any contact with "ground"

[rockgarden]

Timers come in two varieties  - one takes the three prong plug and is the best for aquarium purposes.  The other type take the two prong plug and are best used for turning on and off normal household table lamps and floor lamps.

If you had a wire with a three prong plug coming from your shop lamp  before you took it apart, then you need to change your timer.  

At the lamp end of the cord, the green wire is the ground wire and needs to be attached to something to "ground" your ballast.  In the original setup with the metal frame, the ground wire (green) would normally have been attached by a screw to the metal and this would automatically ground the ballast since the ballast would also be attached to the metal frame.

The simplest approach at the ballast end would be to now attach the ground wire (green) to one of the screws that you used to attach the ballast to the wood and then see if this improves the situation (plug end would need to be attached to a proper three prong enabled timer).

I'm not an electrician. I just saw lots of lighting products installed in funny ways many years ago when I was provincial sales manager for a lighting company. During that time I learned not to play with electricity  :idea:


Also, for safety reasons, aquariums should only be plugged into circuits with ground fault circuit interupter protection in place (GFCI).  I know that many are not (including some of my own) but they definitely should be.

http://doityourself.com/electric/gfci.htm

Ron

[dpatte]

some flourescents will not fire unless in close proximity to metal. I had a similiar problem to yours years ago when i ripped aparts some flours and put them into a multilevel wooden stand.

The problem was solved when i placed aluminum foil between the lights and the wood.

[darkdep]

Fluorescent tubes are designed to be near a grounded piece of metal, or more correctly, a piece of metal with the same electrical potential as the ballast.  An easy way to get around this issue is to install the ballast itself in close proximity to the tubes.  I've done this several times to success.

Alternatively, place some kind of metal (as dpatte pointed out, aluminum foil works, as would sheet metal, etc.) near the centre of the tubes, glue/screw/whatever in place.  Try the lights.  If they still don't work, attach a wire to your metal, and the other end to the metal case of the ballast, and you'll be good to go.

[rockgarden]

The proximity to metal issue applies to almost all fluorescents that are of the"rapid start" type.  These systems establish a brief high voltage potential to create the arcing necessary to get the electrons excited.  The normal distance between tube and metal would be .5 inches or less in a commercial fixture. Older systems with seperate starters don't exhibit this same problem and as far as I know, neither do the newer electronic ballast types.

Ron

[valiko]

I'll just buy some GloMat's for my next aquarium

electronic ballast + moisture resistant end caps ...