one shot timer in a 24V system

[brad@agtronic]

Hi,
I am running a 24Volt DC system. I have a relay that is controlling another device that is a different voltage. I have a 24V trigger to the relay circuit that occurs randomly. I would like the trigger to trip a timer that would keep the relay active for about 500 mS. If the 24V trigger comes in before the timer runs out it will refresh that timer.

I was going to go the 555 timer route but I can't find anything that will run at 24V. I do not want to put a regulator into the circuit.

thank you for your help.

Bradley

 

[ericgibbs]

Hi,
I am running a 24Volt DC system. I have a relay that is controlling another device that is a different voltage. I have a 24V trigger to the relay circuit that occurs randomly. I would like the trigger to trip a timer that would keep the relay active for about 500 mS. If the 24V trigger comes in before the timer runs out it will refresh that timer.

I was going to go the 555 timer route but I can't find anything that will run at 24V. I do not want to put a regulator into the circuit.

thank you for your help.

Bradley

hi,
You could easily make a transistorised retriggerable monostable.
Using MPS2222a transistors, see this link.

Multivibrator - Wikipedia, the free encyclopedia

 

[brad@agtronic]

Thanks for your help. I will use that. I should have remember that from my school days 20 years ago. I am that rusty.

Bradley