[SOLVED] momentary switch time delay

[wozzzzza]

i need to make a simple electronic circuit to do the following but stuck.
i have a momentary switch that is normally closed and when opened de-energises a lock that unlocks a door.
what i want to do i have a circuit that when you press the switch to open its contacts to take power away from the lock to allow the door top open, when you release the switch i want the lock to remain de-energised for around 10 seconds to give people time to open the door when they release the switch when they have got one hand.
how to do this??

 

[KlausST]

Hi,

there are ready to buy timing relays for this.

Klaus

 

[dick_freebird]

Monostable multivibrator (one-shot) ICs can debounce and
extend a mechanical switch event. You'd likely find app notes
for this. Like use a 555 timer IC in that mode and let its fairly
fat output sink, drive a small relay (w/ catch-diode if you want
to preserve contact life).

 

[danadakk]

Are you interested in building something yourself or just an off the shelf
solution ?

Regards, Dana.

 

[wozzzzza]

Are you interested in building something yourself or just an off the shelf
solution ?

Regards, Dana.

either. just looked at an off the shelf one at $45, been out of electronics for soo long now forgotten how to build one.

 

[wozzzzza]

just built one and works perfectly https://elonics.org/adjustable-auto-on-off-delay-timer-circuit-using-555/