timer relay circuit reqest

[steven2]

i am seeking a timer like relay circuit that will run off 12 volts the relay is a 12 volts type i have a draw full and this circuit im seeking must close the relay contacts for a set time between 10 and 15 seconds , then open again after that time pioriod, i spent hours biuding one i got from the net only to find it dident work , as it lacked details that dident help much, id like this circuit to be a tested and or working type. and as simple as possible, and not to large as to take up to much space if this circuit can close a relay contact for 10-15 seconds or even 20 seconds before opening its ok

 

[audioguru2]

Hi Steven,
All you need is a 555 timer IC wired as a monostable like in our Articles section. A momentary pushbutton shorts its pin 2 to ground to start the timing and a resistor and capacitor on pin 6 determine the time period. Connect pin 7 also to pin 6. Its output can drive a relay coil with up to 200mA. Add a diode across the relay coil to arrest its back-EMF spike.

 

[steven2]

thankyou audio guru

 

[steven2]

luckily i found one and ive biult it onto a small prototype board and i used a 12 volts relay instead of a nine volts reay and it works good , i plan to exsperiment with it and use it to shut off the capacitor under charge ,in my high voltage photo flash capacitor chargeing circuit ,after so many seconds of chargeing, so as to not over charge it by letting it charge to long so thr timer relay is what i need