Looking for help replacing a t8 fluorescent ballast

Hey all. So as the title says I’m looking for help finding a replacement ballast for my t8 fluorescent lights. Here’s the issue…

Every replacement ballast I am finding online has 5 wires coming out of it and connects to both ends of the bulb.

Example of wiring diagram for the 5 wire ballasts:

And here’s what my ballast wiring diagram looks like:

The ballast wires only connect to 1 end of the bulbs and the other ends just have a little jumper wire that runs in between the 2 bulb sockets.

More pics of my ballast. It has 4 wires. 2 wires run to one end of the bulbs

And the other 2 wires connect to the power and on/off switch

I have been unable to remove the ballast wires from the bulb sockets.

So my plan if I couldn’t remove the wire was just to cut + strip the wires, leaving some sticking out of the bulb socket and then I’d splice it to the wire on a new ballast.

But that plan was for a direct replacement ballast that was the same as mine.

Every ballast I am finding online is like the one below with 5 wires

Does anyone know of a source for the 4 wire ballasts like my old one? I’ve contacted 1000 bulbs .com and ballast shop .com and neither had the 4 wire ballasts.

I know i can probably just use a 5 wire ballast like the one above and wire it to both ends of the bulbs like the diagram shows. But then I think I’d also need new bulb sockets because I can’t get the old wires out and I’m not sure how I’d wire up the new ones without removing the old wires.
I’m also not sure which terminal(s) on the sockets the wires would even connect to because it doesn’t show it in the wiring diagram.

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You do what you like but I’d argue it’s dead tech and you’re better off spending money on something else.

I just threw away a t12 for the same reason.

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Yeah I know they’re being discontinued everywhere. But I’d like to get a bit more use out of them while ballasts and bulbs are still available.

I’d just buy a new t8 4ft. 2 bulb fixture but they aren’t available for sale anywhere locally. So I figured I’d fix mine.

I just very much prefer fluorescent lights for starting seeds, rooting clones, vegging young plants and especially for keeping my bonsai mother plants healthy for long periods of time.

I have yet to find any LED light that works comparably to fluorescents (and I’ve tried at least 5-6 different brands of LEDs so far).
Fluorescents just fit my grow environment better. I can grow perfectly healthy plants with 0 deficiency issues under fluoro’s.

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There’s two options I can think of for how those wires are held in. Either there is a cap at the bottom of the bulb holder that is removed and the wire is pushed down into the contacts and held in by the “cut” of the wire. Or they are slip fittings. If they are slip fittings it will require a small screwdriver or wago tool pressed into a slot to put pressure on the spring clip and release the wire. You could also just split it and strip them back as pigtails like you mentioned before.

Check with demolition companies. They usually keep stuff like that and sell it for good prices. Edit: this is a possible option for finding used fixtures or ballast

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We used to launch old t12 bulbs as javelins into construction sites.

As to the t8s, if they work they work.

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https://www.grexcavatedemo.com/

These folks are the type of company I’m referring to. They sell al kinds of neat stuff for dirt cheap. Idk if they have any fixtures or ballast right now but couldn’t hurt to check.

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Ebay maybe, theyve got them for t8s maybe usuable.
4 Interface Electronic Ballast 220V T8 Fluorescent Tubes Ballast White New | eBay

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So with flo’s they are dead tech,and being discontinued…i would suggest removing the ballast and getting direct wire led replacement style t8s…using your same fixture while upgrading your setup. Unless you are set on florescent of course then i have no suggestions on new ballast except maybe finding an different fixture. Hope this kinda helps!

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@TeddyNuggets - Toggled - Did this years ago and still running strong…

Toggled Led T8 T12 Led Conversion

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That looks close to what I need but it’s 220v. I’d need 110/120. Thanks for sharing! I’ll see if I can find anything on eBay!

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Thanks @Trickster @Jeepster420

I do have some 4ft LED t8 conversion bulbs tha5 I’ve already tried and some other 4ft LED shop lights but I’m looking to specifically use t8 fluorescent.

I have an old t8 veg light I made by attaching three 4ft, 2 bulb t8 fluorescent lights together and I’d like to start using it again for my bonsai moms. They just stayed way healthier for way longer under the t8 fluorescents. They get unhappy much faster under any of the LEDs I’ve tried.

I realize I’ll eventually have no choice but to use LED.

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Gotcha! Sounds like a pretty cool setup! Good luck on finding a solution!! If you have good bulbs i hope you can find some old fixtures with good ballast somewhere!

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I would look at social media sites. You can find complete lights cheap and use them for parts to keep this style of lights growing … If you get lucky there may be some available locally to you. Check Market Place and Craigslist and offer up along with eBay. Hope you get lucky with your searches… On a side note I still have T-5 great lights lol. I will switch those to led only at last resort haha Cheers !!!

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Yeah I still have t8 bulbs. Just need to find a ballast!

I’m thinking worst case I’ll have to use one of the 5 wire ballasts and figure out how to wire it up.

and see if I can get the wires out of the bulb sockets like @Gadarien mentioned. I could always buy new sockets too if I had to.

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Thanks for the suggestion! I have checked Craigslist and Fb marketplace but I’ll continue checking!

I actually picked up some 4ft, 8 bulb t5 fluorescent fixtures and bulbs off of FB marketplace last year. For cheap like you said. I got two of the 8 bulb fixtures/hoods and like 24 t5 bulbs for under $100.

They are so much better for veg than any LED I’ve ever used. They just cost a lot more on the electric bill to run! lol

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I like mixing the LED with T-5 or T-8 I think it’s a great spectrum. And very little increase in power consumption. I should probably get a few more wear and tear parts as they’re getting harder to come by every year . Cheers !!!

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Yeah, those are definitely different than what I need looking at the wiring charts on them. But I really appreciate you digging them out for me! That was very cool of you to do!

I currently already have like 5 different LED’s I’m using, so I have made the switch. I’ve been trying for like the last 4-5 years to get used to the LEDs. I’ve tried a bunch of them. I LOVE them for flower and they are ok for vegging out plants to get them ready for flower (still prefer fluorescent, metal halide or CMH though).

But for keeping my bonsai moms the LEDs have been a huge PITA for me. As soon as the bonsai moms get rootbound (which happens pretty quick) they start to get unhappy under the LEDs. It’s just a lot higher maintenance to keep the bonsai moms healthy under the LEDs.

It would just make my life easier to get my t8 fixture back up and running for my bonsai moms. And it only uses like 192 watts of electricity, so it’s very comparable to what the LED lights use and won’t raise my electric bill any higher than it already is. lol

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Been meaning to toss these anyways, moving from one project to the next sometimes things like this sit and forgetten about, good luck finding a new ballast, I’m sure there is one sitten somewhere waiting for you to find it…

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It looks like the reason for the 5 wire balast is so the light will still work if a bulb burns out or is removed. Your ballast is wired in series so it cant work if a bulb is out or missing. It should be possible to use a 5 wire ballast in your fixture if it it is rated for twice the wattage of your bulbs. Your wattage is going to double in a series configuration. I’d only try it after ohming out the blue wires and they show they are internally connected (low resistance between them) Or you could snip the jumper and wire-nut leads on.

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I think @Mr.Sparkle or @Nitt might be able to give some insight here.

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