# Battery backup for 1 of 2 T-12 on a single ballast?



## swimmer (Mar 19, 2011)

Can somebody describe how you would wire a battery backup for the following florescent fixture?

Fixture is 2 T-12 bulbs behind a single ballast.
Battery backup will light only 1 of the 2 bulbs when line power is cut.
A test button will be able to to simulate a cut in line power.

Use Lithonia Power Sentry PS-500 if a specific battery backup unit is required for a description.

Thanks


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## Chris Kennedy (Nov 19, 2007)

swimmer said:


> Can somebody describe how you would wire a battery backup for the following florescent fixture?
> 
> Fixture is 2 T-12 bulbs behind a single ballast.
> Battery backup will light only 1 of the 2 bulbs when line power is cut.
> ...


That thing should come with a dozen wiring diagrams. And why mess with T12's, sell them nice new battery back up T8's.


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## frenchelectrican (Mar 15, 2007)

Swimmer .,

Here is the wiring diagram it will be in PDF format so you can print it later if need to.

Keep in your mind there are serveral ways to do this so here the link.,,

http://www.acuitybrandslighting.com/library/LL/documents/otherdocuments/PS.pdf

Hope that help ya.

Merci,
Marc


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## kaboler (Dec 1, 2010)

The first link I went to:

http://www.plccenter.com/buy/Lithonia/PS500

I like the big OBSOLETE thing.


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## Electric_Light (Apr 6, 2010)

swimmer said:


> Can somebody describe how you would wire a battery backup for the following florescent fixture?
> 
> Fixture is 2 T-12 bulbs behind a single ballast.
> Battery backup will light only 1 of the 2 bulbs when line power is cut.
> ...


Read the specs. The power delivered to lamps may not vary much between one vs two lamp operation and this can be a totally unnecessary work. The only time you you need to wire for two lamp is when you absolutely must spread the output across two lamps located sufficiently far apart or around a corner. Emergency ballasts are usually rated in lumen output.

Here's a one or two lamp 700 lumen unit. 
http://www.iotaengineering.com/i48.htm
It will run 1 x F32T8 @ ~700 lm , or 2 x F32T8 @ ~350lm each


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## swimmer (Mar 19, 2011)

Kaboler, First link I visited too.


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## swimmer (Mar 19, 2011)

Thanks French Electrician.
That helped a LOT!


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