What's the effect of using the wrong bulb/ballast combo?

[charles]

dumb guy question

I'm dealing with aquarium lighting, U-tube compact fluorescents. Depending
on vender, time of year, what else, I can't always get what I want in
wattage and color temperature.

Today I installed some tubes marked 55W in a fixture with a ballast marked
65W, other times I've gone the other way, 65W bulbs with 55W ballasts.

My guess, maybe reduced light with the too small ballast, reduced lifetime
with the too small bulb? Nothing has exploded, so I guess there may not be
a physical danger.

 

[TKM]

dumb guy question

I'm dealing with aquarium lighting, U-tube compact fluorescents. Depending
on vender, time of year, what else, I can't always get what I want in
wattage and color temperature.

Today I installed some tubes marked 55W in a fixture with a ballast marked
65W, other times I've gone the other way, 65W bulbs with 55W ballasts.

My guess, maybe reduced light with the too small ballast, reduced lifetime
with the too small bulb? Nothing has exploded, so I guess there may not
be a physical danger.

The general answer is "don't". Get the ballast catalog number and look on
line for the lamps that the ballast can operate properly. Often the lamp
types are marked on the ballast itself. Yes, you can fiddle with different
combinations and some may even result in light; but you don't know if any
particular combination is what the ballast designer had in mind and short
lamp life, ballast faiilure or other nasties could result. For sure, if the
ballast fails and its under warranty, you'll have trouble getting it
replaced if the seller thinks the proper lamp has not been used.

Terry McGowan

 

[charles]

The general answer is "don't". Get the ballast catalog number and look on
line for the lamps that the ballast can operate properly. Often the lamp
types are marked on the ballast itself. Yes, you can fiddle with
different combinations and some may even result in light; but you don't
know if any particular combination is what the ballast designer had in
mind and short lamp life, ballast faiilure or other nasties could result.
For sure, if the ballast fails and its under warranty, you'll have trouble
getting it replaced if the seller thinks the proper lamp has not been
used.

Terry McGowan

I owe you a proper response. Prompted by what you told me I've ordered the
proper bulbs for these fixtures.