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replacing ballast

2856 Views 19 Replies 5 Participants Last post by  sportflyer
One of 3 2 lamp fluorescent fixture in the garage stopped working.

I checked it out and it's one of those instant start series connected setups but with only 4 wires from the ballast. Two input wires and the other 2 ( red , blue) are connected to each tube at one end and at the other end the tombstones are just connected together. All 4 Tombstones are shunted ones. So its definitely a series connection . I think the ballast is shot because replacement tubes don't light up. I tested the continuity between the red and blue wires and it is open , but maybe there are capacitors in series so it will measure open . I don't dare check the voltage at it could be quite high to start the series tubes from cold. Is there an alternative way to test the ballast ?

The ballast is :
ACCUPRO AP-RS-232IS-120 , the equiv is Keystone KTEB-232-UV-IS-N-P T8 Instant Start Electronic Ballast

Suggestions?

Maybe I should just replace the whole thing with a LED version.
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Maybe I should just replace the whole thing with a LED version.
Bingo! Winner Winner steak dinner.

Yes. Don't try to fix them. I assume they are 48"?
You can replace them completely or retrofit the existing fixtures to LED.
Whatever route you take, make sure you never need another ballast as long as you live.
Good luck and be safe.
They are 48 inch . I will replace the whole unit with LED and without ballasts. I will probably have to reuse the casing if I cant find one that matches it.
They are 48 inch . I will replace the whole unit with LED and without ballasts. I will probably have to reuse the casing if I cant find one that matches it.
Replace the tubes with direct wire, dual ended power LED tubes. Eliminates the ballast and reuses the existing fixture with minor wiring changes.

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Can I assume that one of the pins at each end is only a supporting pin so I can reuse my shunted tombstones ? In which case I dont need to remove the fixture to redo the wiring. Its quite simple , I will need a few twist connectors and some lengths of black and white 18 ga wire.
Can I assume that one of the pins at each end is only a supporting pin so I can reuse my shunted tombstones ? In which case I dont need to remove the fixture to redo the wiring. Its quite simple , I will need a few twist connectors and some lengths of black and white 18 ga wire.
You can use your existing tombstones.
Just make sure one end gets a hot and the opposite end a neutral.
Yes, its very easy and worthwhile to do.
You can use your existing tombstones.
Just make sure one end gets a hot and the opposite end a neutral.
Yes, its very easy and worthwhile to do.
Its really like connecting the 2 tubes in parallel . Since its a series connection I do have to cut the wire which shorts the two tombstones together (at one end )and splice a 3rd return wire to either hot or neutral. Same for the other end but in that case no cutting is needed just splicing a 3rd wire . Do the tubes indicate which end is hot ?
Its really like connecting the 2 tubes in parallel . Since its a series connection I do have to cut the wire which shorts the two tombstones together (at one end )and splice a 3rd return wire to either hot or neutral. Same for the other end but in that case no cutting is needed just splicing a 3rd wire . Do the tubes indicate which end is hot ?

No you do not, just take all the wires from 1 end of the fixture and connect to the hot wire (I prefer to do this with the red/blues). Take all the wires from the other end and connect to the neutral (I prefer the yellows). This the method for double ended powered LEDs. It does not matter if the tombstones are shunted or un-shunted.

Some 4 tube fixtures with 2 ballasts have half the red/blues to 1 end of the fixture and the other half of the red/blues to the other. Doesn't matter, all the red/blues to the hot, all the yellows to the neutral.
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BTW nearly impossible to find double ended powered LED tubes at HD or Lowes in 2 packs quantities. Most are 25 packs !(web site) .Changing to single ended power is more of a problem because now I have to replace two sockets at one end with unshunted ones. The sockets are snap fit ones . I need to find replacements before proceeding.
No you do not, just take all the wires from 1 end of the fixture and connect to the hot wire (I prefer to do this with the red/blues). Take all the wires from the other end and connect to the neutral (I prefer the yellows). This the method for double ended powered LEDs. It does not matter if the tombstones are shunted or un-shunted.

Some 4 tube fixtures with 2 ballasts have half the red/blues to 1 end of the fixture and the other half of the red/blues to the other. Doesn't matter, all the red/blues to the hot, all the yellows to the neutral.
My old ballast only has 4 wires... 2 input and 2 output. I dont have a return wire at one end of the fixture. Just the 2 tombstones joined together at one end, which is why I need to cut and splice a 3rd wire .
My old ballast only has 4 wires... 2 input and 2 output. I dont have a return wire at one end of the fixture. Just the 2 tombstones joined together at one end, which is why I need to cut and splice a 3rd wire .
Show me a picture of that, I am conflabbergated.
see attachment


As you can see , just a very high voltage from ballast secondary to the 2 tubes in series . no third wire to ballast .
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see attachment View attachment 594563

As you can see , just a very high voltage from ballast secondary to the 2 tubes in series . no third wire to ballast .
Yes you would have to run a wire from the jumpered tombstones to the neutral.
This one of the few ballasts that have no third wire output . Hard to find replacements which is why I want to replace with ballastless LED tubes. Unfortunately double ended powered ones are hard to find in 2 packs.
Well I happen to like real fluorescents. The light is actually better than LED, and the equipment is reliable - I find LED tech to be a bit dodgy still.

That was definitely a cheapie ballast though. I would go get a better one like a GE Ultramax ($8) ... that one I just linked requires T8 tubes, but you can get T12 ballasts instead if you just don't want to switch to T8.

For cabling it, that is a wacky wiring scheme. Both tombstones at that end need to be connected to the red wire in the new ballast. So split the red. Use blue wire nuts for this. Scavenge spare wires off the old ballast. The GE will perform better and will be able to operate each lamp independently.

Also if you haven't already, go out and get 90 CRI or better fluorescent tubes that are now available at most box stores. You will not believe the quality of the light! (look at the stuff the light is lighting up).
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T12 tubes are being phased out. No sense going with something you cannot get bulbs for.
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I could not find the double ended power T8 LED tubes in single or 2 pack at local stores to minimize tombstone mods or replacement . All I can find are single ended powered ones .The tombstones in my fixture are shunted ones so that I will have to convert both at one end to un-shunted to accommodate single power tubes . I broke the snaps of 2 of them while trying to remove them for conversion so I have to replace . I got so frustrated that I simply bought a new fixture with fixed LEDs for slightly more than the cost of tubes and replacing tombstones . I simply removed the old and remount the new fixture . Simple to do . Its done and working fine
Here is a 2 pack of replacement singled ended tubes for $20. It includes the replacement non shunted ballast. Toggled is a very good brand.

https://www.homedepot.com/p/toggled-48-in-16-Watt-Daylight-Deluxe-T8-Dimmable-Linear-LED-Tube-Light-Bulb-2-Pack-D416-65321-2/308086234?modalType=drawer
T12 tubes are being phased out. No sense going with something you cannot get bulbs for.
I keep waiting for that to happen, and it keeps never happening. I agree, no earthly reason to invest in T12 tech.

I have one site with 500 T12 fixtures and about 80 T5 (!) and not one single T8 on the premises. There, I use T12 for small jobs, otherwise those lights will become orphans. For the record, I plan to go LED on all the archival areas (including the darn T5s) and T8 for the rest.


I could not find the double ended power T8 LED tubes in single or 2 pack at local stores to minimize tombstone mods or replacement.
Yeah, instant start are a pain like that. Keep in mind, the reason they make them single-ended is to save a penny, which just reflects how cheap LED replacement "tubes" are.

And tombstones aren't designed to have 120V across those two pins like that, so I do not like single ended. Nosiree Mr Horse.

I got so frustrated that I simply bought a new fixture with fixed LEDs for slightly more than the cost of tubes and replacing tombstones . I simply removed the old and remount the new fixture . Simple to do . Its done and working fine
Good for you. Sell your old fixtures on Craigslist. People like me love em (90% for LED conversions, but nevermind that lol).


Here is a 2 pack of replacement singled ended tubes for $20. It includes the replacement non shunted ballast. Toggled is a very good brand.
Yes, I am suitably impressed by both the maker and the price. Go ogle Earth says they're in a building that looks like a factory (big, loads of parking, awkward few truck docks). I'll stick a couple in my 24x7 lights and see how they perform. They'd be a good fit for the archival areas I mentioned.
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Here is a 2 pack of replacement singled ended tubes for $20. It includes the replacement non shunted ballast. Toggled is a very good brand.

https://www.homedepot.com/p/toggled-48-in-16-Watt-Daylight-Deluxe-T8-Dimmable-Linear-LED-Tube-Light-Bulb-2-Pack-D416-65321-2/308086234?modalType=drawer
I was looking for double ended powered LED tubes. Cant find them in small quantities.
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