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LED Plexiglas Table, newb needs assistance please!

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Can't confirm the 'charger' because it's not a regulated voltage supply. Calling it a 'charger' means it's probably an unregulated wall wart. REsistors are fine, and I won't have time to look up the UPS right now.
 
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Thanks a bunch for the help Sceadwian, I will go ahead and order the resistors, or maybe just call around and find some tomorrow. That way I can wire everything together and have it ready for the UPS.

I'll look for a regulated charger too. And that's fine about the UPS. I will wait on that also.
 
That adapter looks nice.

Here's a link to APC's website for the runtime chart on that UPS you linked
Runtime Chart for Back-UPS ES

In case you can't read it the model you picked will run at 50 watt load for over an hour, you're running less than 10 so you should get substantially more time (exactly how much I'm not sure because the UPS may not be as efficient so lightly loaded) Think about the UPS a bit, it's obviously fine for a few lights, but if you intend to use it for anything else you'll need to figure out what kind of run time you'll want.
 
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Well, everything that I couldn't find local has been ordered! I know I still don't understand everything, so correct me if I'm wrong but, a few posts back, you said I will need to wire the LED's in sets of 3. If there is a 12v source, and that is divided among 3 LED's, wouldn't that be 4v a piece? Or are the resistors taking care of that?
 
If each LED drops 3.4 volts * 3 that's 10.2 volts. The 100ohm resistor will drop the other 1.8 at 12 volts (all values are approximate) The LED's are the primary variable, but I've never seen a white LED that drops less than about 3.1 volts at it's rated current, so worse case you're looking at 27ma. If you go with the median of 3.2 volts it's 24ma exactly. The values I picked should give you maximum brightness and worse case they should only be very slightly over the recommended forward current.
 
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