Ballast and Lamp questions

[jflng]

I recently bought an advance f32t8-f17t8 electric instant start ballast for a fixture housing 4 24" t8 lamps. I called their customer support just to clear up a few questions I had.
I was under the impression that this rated ballast would run 24" 20w bulbs fine.
They told me that odd wattages like 20w bulbs were for magnetic ballasts only. I could have sworn I read where people used these ballasts for 20w or even 18w bulbs.
So does this mean that I have to use 17w bulbs only with this ballast? I really don't want a magnetic ballast to run my desired bulbs.
They also said mounting the ballast on wood voids their warranty. Do I have to mount it on something like aluminum to be safe. Would wood mounting be fine if I had a fan to cool it?

[rlong]

hi,
I don't know anything about your ballast or bulbs so I can't help you there, but when I mount a ballast on wood I like to put 1-2 washers between the ballast and the wood. I put the screws throught the washers and under the ballast. This helps keep the ballast and wood both cooler.

[mrkookm]

Originally Posted by jflng

I recently bought an advance f32t8-f17t8 electric instant start ballast for a fixture housing 4 24" t8 lamps. I called their customer support just to clear up a few questions I had.
I was under the impression that this rated ballast would run 24" 20w bulbs fine.
They told me that odd wattages like 20w bulbs were for magnetic ballasts only. I could have sworn I read where people used these ballasts for 20w or even 18w bulbs.

Customer support is not going to give you the ok the use their ballast to overdrive your lamp Don't worry your ballast from what I see is capable of firing both 32watt and 18watt 'never heard of 17' T8 lamps. It should fire 20watt lamp at 32watts no probs. Just follow the diagram as if you are wiring a 32watt lamp.

So does this mean that I have to use 17w bulbs only with this ballast? I really don't want a magnetic ballast to run my desired bulbs.

You never want to use a mag ballst anyways, they get scary hot

They also said mounting the ballast on wood voids their warranty. Do I have to mount it on something like aluminum to be safe. Would wood mounting be fine if I had a fan to cool it?

I have installed my fluorescent ballast into my wood canopy with halide lamps and they still work like a champ but the cooler you can make them the better.
The important thing here is to use your best judgment regarding safety or other possible hazards.

[jflng]

Thanks for the great help guys. I suspected that I could still use this ballast. I just wanted to make sure. I think I'll add a fan for cooling anyway.
Oh, and good idea about the spacers. I was thinking of making some kind of heat sink, but I think I'll just use washers as you said.