Help wiring fluorescent brick ballast for use with add-a-taps

Matt Irwin · January 8, 2006

Hey Everyone,

For the past few years I?ve had several 4 bank t12 electronic brick ballasts wired with add-a-taps and used in some home made units. It?s pretty simple?there?s the ballast, a head-to-ballast cable consisting of 4 strands of zip cord inside a ?snake? tube with add-a-taps and plugs at either end, and the head wired with individual tube taps with add-a-taps on the pins and a plug connecting to the h2b cable. I?m making some more units and therefore need more ballasts which is where my problem comes in?

The only 4 bank t12 ballasts I could find are magnetic and 18 inches long (the others are 9 inches) and have a completely different wiring pattern. There are two power inputs instead of one (each line in powers 2 tubes), and there are 4 yellow, 4 blue, and 4 red leads instead of 2 apiece. With my old ballasts I was able to wire them so there are 4 taps on the ballast and each tap feeds 1 of the 4 tubes. That configuration also allowed the use of 1,2,3, or 4 tubes?not just 2 on or 4 on.

I bought 9 of these new ballasts and after frying one while trying to adapt it to the add-a-taps, I decided to wire the ballast to 4 tubes exactly as the wiring diagram shows, pin for pin, and then work from there. I used butt splices to connect to each pin and wire nuts with zip cord to temporarily extend the colored leads. I tested this configuration (picture below) and it works. I?m not an electrician, so my ?wiring intuition? is not all that good. Basically I?d like to figure out the simplest way to wire these ballasts for use in the same way I?ve been using the old ones (ie: ballast > head-to-ballast cable > head). I don?t need to use the ballasts interchangeably.

Here is a PDF spec sheet on the ballast: http://www.advancetransformer.com/eCatalog...10020679291.pdf

And the wiring diagram (in WMF format for some reason): http://www.advancetransformer.com/ecatalog...Art/FWDIA25.WMF

And some pics of the wiring I did to copy the diagram:

Thanks in advance for any help,

Mitch Gross · January 8, 2006

I have a bunch of these I've built as well and all my ballasts are the older 9" type as well. I will say that rather then using wire nuts I attached a bunch of Add-a-tap sockets and then the runs from the ballast to the bulbs was done by simple zip wire extension cords. I strapped them together at appropriate lengths using color-coded electrical tape as it looks like you are doing, and the cabling on the ballasts is strapped in place with some electrical tape and plastic cable ties. Don't know if this has been of much help, but if you have 'em working, then clean it up and call it a day!

Matt Irwin · January 8, 2006

Yeah, I have my 9" ballasts wired exactly how yours are. I used wire nuts in this case as just a temporary setup to better visualize how these new ones work (my "wiring intuition" is not very good).

Looking at the ballast this morning, I realized that I could make this work with 6 taps on the ballast, 6 strands of zip cord in head cable, and then do all of the wierd combining and crossing over with the tube harnesses. I would just have to color code everything and voila! The 2 AC lines in combined with a cube tap would work as a "1/2 ON > FULL ON" function.

On a slightly related note...

I've heard that using add-a-taps with fluorescents is "illegal" on union sets. Can anyone confirm or deny this? If it's true... why?!

Mitch Gross · January 9, 2006

On a slightly related note...
I've heard that using add-a-taps with fluorescents is "illegal" on union sets. Can anyone confirm or deny this? If it's true... why?!

Add-a-taps are meant for use with 120VAC power, not what is coming through those ballasts. To use them in any other way is against various safety protocols and is considered "electrically unsafe." That's essentially because someone who didn't realize what they were looking at could plug a flo directly into a household wall socket and the bulb could explode. I had an overeager PA do this once with one of my rigs and caught it in time to save her life but not the bulb's.

Any electrical gear that does not meet various regulatory standards could negate the insurance covering the production, and as so are banned from any major production. That doesn't mean they aren't there, but officially they are not supposed to be.