Hi all,
since many of you have talked me through building a hen door opener/ closer with SPDT relays which allows concurrent lighting of a 12VDC light, I would like to add a feature of a time delay (motor has a 5 sec delay after 12VDC is received) as such:
12VDC signal is sent to motor which draws average 1-3A, max 5A, but gets interrupted possibly with a 555 circuit, which allows a beeper to go off until 5 seconds elapse, then the current is allowed to continue to the motor.

I thought I had this figured out with the below circuit until I realized: the 555 works the other way around: it allows flow for a time specified by R and C, then actually goes off on pin 3.
Is it possible to work it how I need it - meaning, output to motor is delayed for 5 secs, then goes high?
This is what I found online:


Rainer

 

What you have there is a motor speed controller, if you want a delay start, you need to hold pin 4 low for the duration of the delay, then make it high to run the motor.

So adding a 1Meg ohm resistor on pin 4 to pin 8, and a 4.7uF cap from pin 4 to pin 1, will give approx 5 seconds delay .

 

TY UK!
Before I start changing the schematic - I leave the current schematic as is and keep pin 3 as output?

Rainer

 

yes,

 

TY again!