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Mystery part! Answered

My sister brought me home this part tonight from tech crew at school, she says she thinks it came from a fire alarm but were not sure. There are 2 lightbulb sockets and engraved on the metal it says "75W -125 v". Out of the back there are 6 wires, 1 red 1 black 2 white that are going into the large thing in the middle, and 1 black and 1 white coming out of the empty socket. the 2 sockets are also wired together. What is this part? is it simply a power supply with 2 light bulbs? The label says "Lithonia emergency systems on it" "input : 277 at 60hz (wht and black) output:120v 21.6VA (wht and red).


Some sort of transformer? Maybe a bell ringing device. try powering it up if you're the daring type... Would suggest lots of safety measures if you do though.

so, solder in a plug to the white and black coming out the end and i have a lamp?

. 277VAC is one leg of Wye-connected/3-phase/480VAC to ground. Pretty dang common.

. PS: which leads me to believe this unit came from an industrial setting.

Yeah, that is what I was attempting to convey (not very well I see :-)

. Well, most ppl that know me will tell you that I miss the obvious quite often. :) . In a DIY setting, such as here, I guess it's fair to call 277 odd-ball, but for emergency lighting, it's very common.

I know the feeling about missing the obvious (sometimes I come up with the most convoluted way to solve a problem, and someone else will say, "Why don't you just unplug it overnight?" Um, duh, yeah LOL

Yeah, I remember when they redid our building (where I work) and tore out all the fluorescents, emergency backup lighting, and exit signs, and I asked about them, they said I would not be able to use them at home, for this reason.

. It's an exit sign. The orange connector (black & red wires) goes to a battery/charger.

I think its just from those illuminated exit signs. Its just a 220 to 120 transformer.

If it is in the USA, it is more likely an odd voltage rating as they do this to deter theft.