Electronic Circuit Help

[ComputerWizKid]

I have frequent power outages (I live in a rural area outside a city) I have a CyberPower UPS but what I want to do is have a lamp come on if I lose power and then go off when power restores. I don't know alot about electronics but I think what I want to do is simple right? Here's what I think I need to do but again I have little electronics knowledge I have a extra 5VDC/12VDC transformer that will be plugged into the surge only (When the power goes out those outlets loose power) and then a relay comes in to switch on the lamp (9W CFL) when the the DC 5V or 12V goes dead the relay will switch on the lamp which will get power from the battery backup outlets. I just need help with what kind of relay to get and how to wire the high and low-Voltage parts
Thanks

 

[PM650]

What you need is a SPDT or DPDT relay; a SPDT/DPDT will have both normally open (NO) and normally closed (NC) contacts but most SPST/DPST relays will have only NO contacts, which is useless for your application. It is perfectly fine to leave the neutral line connected and only switch the hot line for the lamp, so you can use a SPDT relay (they're also cheaper). Make sure to get a relay with contacts rated for at least a few amps, some low-level signal relays tend to be rated for 1-2A, but I would not recomend using one for this. some potential candidates

Here's a guide to do exactly what you want, (yours would just use the other pin of the relay contacts): http://sound.westhost.com/project118.htm

Also, here's what you should have for your exact situation: schematic, you'll probably need to include a fuse before the relay. C1 may not be necessary since the CCFL will not have a large inrush current.