2 12V Ins With 1 12V Out Wiring

The relay to be used is found here http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fnam....I need to wire this relay to have (2) 12 Volt Inputs and (1) 12 Volt Output. Power is always to be taken from Input #1 unless its power is cutoff. Then the relay needs to switch automatically to Input #2. Its for a battery backup system. If the AC power is shutoff and my DC Power Supply shuts off, I need the battery backup to kick in instantly without me having to flip a switch in case im not home at the time.I dont know if the image uploaded right or not but i guess well find out.

i guess it didnt   plz tell me how to upload them right and ill post it

not sure of the connections for that as I can't see a pic... but it would be simple using a bosch 5-pin spdt relay. dc supply + to pins 86, 87a dc supply - to pin 85 batt backup to pin 87 12 volt output pin 30

when you say battery backup to pin 87, do you mean pos or neg to pin 87 Same with the 12volt output, pos or neg out???

never mind i igured it out               thanx anywho though