# Ballast and fluorescent socket question



## Funkadelicfred (Jan 30, 2019)

Just an apprentice so be gentle. I was changing a ballast out today and had to put in a new one that I had to rewire a bit (had to make the far ends of the lights take the yellow path back to the ballast instead of just going in blue and coming out red.) 
I wasn't sure what to do with the little yellow jumpers between the sockets because as far as I could tell, if I'm jumping them together then why do I need two blue hots anyway? I guess what I'm saying is I don't quite understand fluorescent bulb fixtures and how they work if everything is jumped together anyway. 
Can anyone shed some light on this?


----------



## Funkadelicfred (Jan 30, 2019)

I was converting a basic ballast that had two blues to two sockets seperately and one red as a return to the ballast. The new one had two blues into one socket, two reds (had to add one to the fixture itself) into the socket beside it and the other ends had one yellow jumping the two sockets together and two other yellows returning to the ballast.

Sorry for the awful drawing but I think you get the gist.


----------



## Funkadelicfred (Jan 30, 2019)

https://imgur.com/a/hE52cfk


----------



## Jarp Habib (May 18, 2014)

Well, either you replaced a 2-lamp instant start ballast with a 4-lamp instant start ballast, or you replaced a 2-lamp instant start ballast with a 2-lamp rapid/programmed start ballast. They have the same number of wires, but very different application. Doublecheck the wiring diagram on the ballast. If you're converting instant start to one of the other types, you need to remove those jumpers at the tombstones.


----------



## Funkadelicfred (Jan 30, 2019)

Jarp Habib said:


> Well, either you replaced a 2-lamp instant start ballast with a 4-lamp instant start ballast, or you replaced a 2-lamp instant start ballast with a 2-lamp rapid/programmed start ballast. They have the same number of wires, but very different application. Doublecheck the wiring diagram on the ballast. If you're converting instant start to one of the other types, you need to remove those jumpers at the tombstones.


Option 2, I'm assuming. It was a 2 lamp replacing a 2 lamp. We went to Ideal to get a replacement and that's what they gave us. My question is mainly why are there the yellow jumpers connecting the tombstones together?


----------



## trentonmakes (Mar 21, 2017)

Typically yellow is the neutral.
Tombstones are jumped out

The red and blue feed the other end

Sent from my LG-K550 using Tapatalk


----------



## trentonmakes (Mar 21, 2017)

This one the 3 blues feed it and red is the neutral...you can see red jumped out in the wiring diagram









Sent from my LG-K550 using Tapatalk


----------



## Funkadelicfred (Jan 30, 2019)

This is very unfortunate because I had a pic of the wiring diagram but I wasn't allowed to post it and now I don't have it anymore but I'd like to figure this out. My picture in the second post is accurate, just crappy, and it worked that way because I did it according to the diagram on the new ballast, a Phillips Centium.


----------



## Funkadelicfred (Jan 30, 2019)

The old setup had one blue feeding the end of one light and one blue feeding the end of the other light, side by side. Other end had a return on one of the reds and the tombstones on the return end were jumped together.
The new one has the two blues feeding one light, two reds feeding the other light, and the two yellows as returns. 
So why does it need two yellows as a return if the return tombstones are jumped together already? Wouldn't one suffice? And what does putting the extra blue and the extra red accomplish?


----------



## trentonmakes (Mar 21, 2017)

Funkadelicfred said:


> The old setup had one blue feeding the end of one light and one blue feeding the end of the other light, side by side. Other end had a return on one of the reds and the tombstones on the return end were jumped together.
> The new one has the two blues feeding one light, two reds feeding the other light, and the two yellows as returns.
> So why does it need two yellows as a return if the return tombstones are jumped together already? Wouldn't one suffice? And what does putting the extra blue and the extra red accomplish?


Sounds like you installed a 4 lamp ballast

Sent from my LG-K550 using Tapatalk


----------



## Funkadelicfred (Jan 30, 2019)

trentonmakes said:


> Funkadelicfred said:
> 
> 
> > The old setup had one blue feeding the end of one light and one blue feeding the end of the other light, side by side. Other end had a return on one of the reds and the tombstones on the return end were jumped together.
> ...


No it was the one in the pic but it shows two lamps.


----------



## trentonmakes (Mar 21, 2017)

What Jarp said,

That pic if i googled correctly is a rapid start ballast.

Sounds like the older one was instamt start ballast and needed the jumpers in the tombstones.

Sent from my LG-K550 using Tapatalk


----------



## Funkadelicfred (Jan 30, 2019)

But I left the jumpers in and it worked. I removed them and the light wouldn't turn on and when I put them back it worked again.


----------



## Jarp Habib (May 18, 2014)

Funkadelicfred said:


> Option 2, I'm assuming. It was a 2 lamp replacing a 2 lamp. We went to Ideal to get a replacement and that's what they gave us. My question is mainly why are there the yellow jumpers connecting the tombstones together?



T8s have two pins because there is actually a heating element in between them. In the old days of analogue circuits with pure inductive ballasts, lamps had to be started by completing a circuit between just the pins themselves so that the ends (cathodes) would warm up, which made it easier to strike the ion flow across to the other end. A fluorescent starter was used to basically short the circuit through the paired pins for a few seconds, and it would then open itself up to take itself out of the circuit. With the starters out of the circuit, the remaining circuit usually had the lamps wired in series with each other. That's why it looks like there's an extra yellow jumper: because the lamps are wired in series with each other. 

That's also why on the instant start ballast, there are jumpers (shunts) across both halves of each tombstone. Instant starts rely on pumping a high voltage spike across the ends of the lamp so they don't need to take the time to heat the ends up, thus they short the two pins together with shunts. That high voltage spike tends to blast the electrodes apart faster than rapid start the more they're switched on and off, so lamps will burn out faster if they're switched, but they use less energy because they don't have the whole heater thing. The last time I checked, I was messing around with an old analogue emergency exit sign with dual 5W T5s. Measuring resistance across pins (through the heaters) gave something like 40W at 277V, which is why the interior of the thing was half melted and crumbling to dust because the lamp changer dude never thought to change the starters and they'd fail with the heaters stuck on permanently 

Three good links here:

https://previews.123rf.com/images/d...nt-lighting-circuit-simple-vector-diagram.jpg

https://www.halcolighting.com/pdf/WP/T8-IS-Retrofit.pdf

http://www.electrical101.com/series-ballast-wiring.html


----------



## Jarp Habib (May 18, 2014)

Basically, you've got a programmed start ballast managing to work as an instant start ballast. 

Compare your "new" wiring here: https://imgur.com/a/hE52cfk

With the actual wiring of a 2-lamp ICN-2S54: https://a89b8e4143ca50438f09-7c1706...riginal/advance-icn2s54t-specs.pdf?1440204063


----------



## Funkadelicfred (Jan 30, 2019)

Jarp Habib said:


> Basically, you've got a programmed start ballast managing to work as an instant start ballast.
> 
> Compare your "new" wiring here: https://imgur.com/a/hE52cfk
> 
> With the actual wiring of a 2-lamp ICN-2S54: https://a89b8e4143ca50438f09-7c1706...riginal/advance-icn2s54t-specs.pdf?1440204063


Ok I see. I hope that isn't a problem then that the ballast types are different.


----------



## Jarp Habib (May 18, 2014)

Funkadelicfred said:


> Ok I see. I hope that isn't a problem then that the ballast types are different.


Depends on the installation. If a bunch of lights are installed together, it may be called into question why one light always takes longer to start than the others. Realistically speaking, as long as the wiring has been corrected, unlikely to be noticed. Couldn't tell you how long things will hold together with it wired kinda halfway in the middle.


----------



## tmessner (Apr 1, 2013)

use the hybrid led. Problem fixed always, any socket


----------

