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Fred McKenzie

In article ,
wrote:

I have a "Lights of America" Florescent fixture (4 ft - 2 bulb shop
light).

Only one bulb would light. New bulbs did not fix it. Only one side of
the fixture worked. (Always the same side).

I finally tore it apart.

I have repaired and replaced ballasts in a lot of fixtures, but this one
is unique. Instead of having one ballast for the entire fixture, this
one has thick plastic ends, with one ballast on each end. These ballasts
look more like a small transformer or a choke used in power supplies on
electronics. Across the wires on each ballast is a capacitor and a
resistor. The choke on one end looked ok and that fed the bulb which
worked. As soon as I opened the other end, I found the problem. That
capacitor literally had a hole in it, and there was black burnt markings
around it.

The good capacitor is not labeled like a normal cap, so I dont know what
value it is. It says K 505J 250. (I am guessing its 250 volt, but I am
clueless about the uf value).

Either way, I am sure that finding a capacitor that will work, would
only be a guess...

But I am posting this for another reason. The wires that cross over to
the defective side, are joined in the middle of the fixture with a
sealed plastic box, which can not be opened. I put my VOM across those
wires and there is no reading (on the ohm setting). Is that a fuse, or
what? Like I said, I have never seen this type of setup. Every fixture I
have ever opened just had straight thru wires, or used wirenuts to join
splices.

I can only guess that when the cap shorted, it blew the fuses or
whatever is in that thing...

Have any of you ever seen this type of setup?

I'm only asking this because I am curious. I do not intend to buy a new
ballast, which would probably cost as much or more than a new fixture.
However I may convert this fixture to 4 ft LED replacement bulbs, which
means removing all ballasts and directly wiring the sockets to the AC
line (only one one end of the bulbs). I was kind of thinking of
converting the fixture to LED anyhow, so now I have more reason to do
so.

Oldschool-

You caught my interest, since I have been slowly changing some old
fluorescent fixtures for LED.

I'm thinking your capacitor may use a standard method of marking:
significant digits 5 and 0 followed by 5 zeros, and a J to indicate 5
percent. This is in picofarads, so the result would be 5 microfarads.
I agree that the 250 would be voltage. I would expect such a capacitor
to be non-polarized.

I once found a similar fixture, but the two sides were just independent.
Each had an inductor for ballast, but used a starter for each. I think
yours may be the modern equivalent that does not use a starter.

My thought would be to replace the entire fixture, not just convert it.
The cost may be similar, but the result may look and work better.

Fred