[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Subject: 2 bulb ballast for 1 bulb

>Is there a way to safely wire up a 2
bulb T8 ballast to just light a
>single bulb? With only a single bulb in
the circuit, the lamp won't
>light. :-[
I do not see how you can do this in a
series ballast without putting all the
drive current through just one bulb.
You can of course achieve this with a
parallel ballast the remaining tubes
stay lit even if one is removed. That is
why I think parallel ballasts are a good
choice for DIYers. A single ballast can
drive 3 or 4 or even 2 tubes at
different ballast factors. I believe
that you can even use the same ballast
to run multiple power compacts or high
lumen biax bulbs or whatever you want to
call them. (I have not tried this) One
confusing thing about parallel ballasts
is that they are all instant start which
while they are slightly more efficient
than rapid start systems tend to be
harder on tube life. This however does
not apply when using long start times
like in a planted aquarium. So all other
things being equal one might as well
purchase a parallel ballast as they can
be used in many different ways.

Wayne Jones