Electronic Ballast conundrum


Senior Member
I am rewiring a menu board that has four F36 high output T12 lamps. The supply house doesn't sell the magnetic ballasts anymore so I had to buy the electronic. The 4-lamp diagram on the ballast shows that four blue wires each go to a socket for one side of each lamp to connect in. The two red wires connect two of the four sockets each for the other side of the lamps.

Each lamp socket has two wires connected to them. On the blue side (4 sockets) I spliced the 2 black wires (from socket) to one blue wire coming from the ballast. I did that for each of the 4 sockets that were to connect one side of the lamps.

On the other side (4 sockets) I connected the 2 black wires from two sockets together with one red wire. I did that twice to connect the other side of the lamps.

There were four blue wires and two red wires coming from the ballast.

If this is not confusing can anyone let me know if I did something wrong because the lights didn't come on.? And I connected the hot and neutral wires of course.
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Senior Member
I think you have the wrong ballast, the ballast you wired sounds like one for F32 T-8 lamps, if they have resesed pins on the lamps then these are HO type lamps and will not fire off on a T8 32 watt ballast.
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Senior Member
The lamp type conventions are extremely confusing especially with all the energy saver lamps out there. I recommend you always hang onto the old lamps until things are done especially when you're dealing with signs as they sometimes have unconventional length (like 31 inches). You may have been given a standard F40T12 F34T12 48" T12 ballasts.


yy always mean n/8th of an inch tube diameter, so T8=8/8 = 1 inch, T12= 12/8 =1.5inch

The xx values can mean the length in inches or nominal watts.
F32T8 = 32W, T8 bulb, 48" nominal.
F25T8 can mean either 25W T8, 48" high level energy saving lamp.. OR 25W T8 36" regular.
F96T8 is not a high output, but its an 8' single-pin 59W 96" T8.

T12/HOs lose output rather quickly and they're rather inefficient. You'd have to change and reposition the sockets a bit, but if you can get it to fit, you should be able to get away with using 36" F25T8/850 or 865 (run of the mill T8 3 footer) and run it on high BF ballast which runs the lamps at 140% output. (0.87 vs 1.20). It won't be as bright as new T12/HO, but should match that of existing lamps. You could use something like GE UltraMAX T8 high light 6 lamp. These are used for 6-lamp high bay light.