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.

On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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).

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.

Why they cant label their caps like normal people, is frustrating, but
that's how they do it. Just more complication for no advantage. Kind of
like metric bolts.... The SAE bolts were just fine, but they had to
complicate matters and force everyone to buy and own TWO sets of tools.

In article ,
says...

Why they cant label their caps like normal people, is frustrating, but
that's how they do it. Just more complication for no advantage. Kind of
like metric bolts.... The SAE bolts were just fine, but they had to
complicate matters and force everyone to buy and own TWO sets of tools.

Only if you still cling on to your bushels and pecks...

Mike.

wrote:
On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.


J=+/-5% tolerance.

http://www.dummies.com/programming/electronics/capacitor-tolerance-code/



Why they can't label their caps like normal people, is frustrating, but
that's how they do it. Just more complication for no advantage.


That is a standard marking. You need to study the basics, instead of
constantly complaining.


--
Never **** off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)

On Sat, 01 Apr 2017 11:13:03 -0500, wrote:

On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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).

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.

Why they cant label their caps like normal people, is frustrating, but
that's how they do it. Just more complication for no advantage. Kind of
like metric bolts.... The SAE bolts were just fine, but they had to
complicate matters and force everyone to buy and own TWO sets of tools.
Be careful you don't bite your tongue while it is firmly planted in
your cheek.
Eric

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

On Sat, 01 Apr 2017 12:45:49 -0400, Fred McKenzie wrote:


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

Your right about those caps. Funny thing, I began working on electronics
around 1965. I have never seen a cap marked like that till now. All I
have seen all those years were either marked uf, MFD, uuf MMFD, or PF.
And some of them real old ones with colored bands and dots that make
them look like a domino.

Yep, both sides are independent on this fixture. I think those 5uf caps
replaced the starter.

I looked at the cost of a new fixture. The LED ones complete with bulbs
are around $60. I can get the bulbs for about $7.50 each. Theres no
sense spending the extra $45, when this fixture is just fine. Except for
the socket ends and the cord, all I am re-using is the metal/plastic
shell. And since I ripped out the guts, I gave it a good hose cleaning
and it looks almost like new.

Besides that, I think the NEW fixtures are all plastic. I like metal
better.

On Saturday, April 1, 2017 at 12:14:12 PM UTC-4, wrote:
I can only guess the "J" means Japan.

Why they cant label their caps like normal people, is frustrating, but
that's how they do it.

Americans make up less than 5% of the world's population. We consume 25% of the world's total natural resources. By any reasonable or unreasonable measure, we are hardly "normal" people.

Get over yourself.

Peter Wieck
Melrose Park, PA

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.

I wouldn't bother it because if a fire results afterward, then the insurance might not pay. I'd call a lighting retailer to send someone out to fix or replace it.

On 4/1/2017 3:21 PM, wrote:
On Saturday, April 1, 2017 at 12:14:12 PM UTC-4, wrote:
I can only guess the "J" means Japan.

1967, North High School, Earth Science class, Mr. Hillier.
Points to the letter W on the periodic chart, "John, what element is
this?"
"Uh, water?"

Why they cant label their caps like normal people, is frustrating,
but that's how they do it.

Get over yourself.

This *is* how normal people label capacitors:
https://www.mikesarcade.com/arcade/images/capcode.gif

I work on vintage radios along with "new" stuff.
How they marked things has changed over the years.

Paper dielectric capacitors for example were marked
0.002 MFD 400 WVDC |
value, voltage and which end was the outside foil.
The only "not the same" ones were the Sprague "Bumble Bee" black
plastic bodies which didn't matte, because they all need to be
replaced anyway.
Back in the '70s when I first started work in the aerospace
industry, capacitors that we used were all marked with the number
system, 104 for example for 0.01 uF. (And that was uF, not MFD.)

I remember reading a mil-spec definition for some capacitors where
then specifically assigned random numbers in place of the values.
This way you had NO idea what the value was unless you had the
"secret Captain Video decoder wheel." This was supposed to cut down
on employee theft of components.

During the early '30s, just to make things a little more interesting,
they used the letter M instead of K for "thousands of ohms" on the
schematics, so a 47,000 resistor was marked 47M, not 47K. The Meg
was used to bigger values, 1,000,000 was 1 Meg. But I'd get the
occasional questions, "Where can I get a 120 meg ohm resistor?"




--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

---
This email has been checked for viruses by AVG.
http://www.avg.com

wrote in message
news
On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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).

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.

J is quite likely to be the tolerance code.

Electronic starters can improve a flaky fitting - but I'd just rip it out
and fit electronic ballasts, you get more light and/or less electricity
bill. The tubes also last a lot longer.

LED "tubes" are starting to appear on the market - you can probably expect
better than half the electricity usage.

Leaving the PFC capacitor in can take the edge off mains spikes, but to
protect an electronic ballast, a MOV is worth the effort.


---
This email has been checked for viruses by AVG.
http://www.avg.com

"Michael A. Terrell" wrote in message
...
wrote:
On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.


J=+/-5% tolerance.

http://www.dummies.com/programming/electronics/capacitor-tolerance-code/

My thoughts too - but 5% seems a bit too good for a PFC capacitor.


---
This email has been checked for viruses by AVG.
http://www.avg.com

Benderthe.evilrobot wrote:

"Michael A. Terrell" wrote in message
...
wrote:
On Sat, 01 Apr 2017 05:43:34 -0500, wrote:

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

I did figure out one thing on my own (using Google).

505J is a Japanese way of marking a cap. In this case, it's 5uf.
So it's a 5uf at 250V cap. I can only guess the "J" means Japan.


J=+/-5% tolerance.

http://www.dummies.com/programming/electronics/capacitor-tolerance-code/


My thoughts too - but 5% seems a bit too good for a PFC capacitor.


1% would be excessive, at 5 uF. It's easy to make 5% film capacitors.


--
Never **** off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)

Foxs Mercantile wrote:
On 4/1/2017 3:21 PM, wrote:
On Saturday, April 1, 2017 at 12:14:12 PM UTC-4, wrote:
I can only guess the "J" means Japan.

1967, North High School, Earth Science class, Mr. Hillier.
Points to the letter W on the periodic chart, "John, what element is
this?"
"Uh, water?"

Why they cant label their caps like normal people, is frustrating,
but that's how they do it.

Get over yourself.

This *is* how normal people label capacitors:
https://www.mikesarcade.com/arcade/images/capcode.gif

I work on vintage radios along with "new" stuff.
How they marked things has changed over the years.

Paper dielectric capacitors for example were marked
0.002 MFD 400 WVDC |
value, voltage and which end was the outside foil.
The only "not the same" ones were the Sprague "Bumble Bee" black
plastic bodies which didn't matte, because they all need to be
replaced anyway.
Back in the '70s when I first started work in the aerospace
industry, capacitors that we used were all marked with the number
system, 104 for example for 0.01 uF. (And that was uF, not MFD.)

I remember reading a mil-spec definition for some capacitors where
then specifically assigned random numbers in place of the values.
This way you had NO idea what the value was unless you had the
"secret Captain Video decoder wheel." This was supposed to cut down
on employee theft of components.

During the early '30s, just to make things a little more interesting,
they used the letter M instead of K for "thousands of ohms" on the
schematics, so a 47,000 resistor was marked 47M, not 47K. The Meg
was used to bigger values, 1,000,000 was 1 Meg. But I'd get the
occasional questions, "Where can I get a 120 meg ohm resistor?"


Use two 60M focus resistors in series.


--
Never **** off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)