Power delay timer with three relays.
OFF delay time and ON delay time are changeable by changing values of capacitors or resistors.
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Off delay time determined by the capacitor in the right hand side that which its capacity now is 5uf .
You can change it like this :
CAPACITY FREQUENCY DELAY
5uf :: 80mHZ = 12.5sec
10uf :: 40mHZ = 25sec
20uf :: 20mHZ = 50sec
40uf :: 10mHZ = 100sec
80uf :: 5mHZ = 200sec
160uf :: 2.5mHZ = 400sec
320uf :: 1.25mHZ = 800sec
640uf :: ~ 0.62mHZ = 1600sec
1280uf :: ~ 0.31mHZ = 3200sec
2560uf :: ~ 0.16mHZ = 6400sec
5120uf :: ~ 0.08mHZ = 12800sec
10240uf :: ~ 0.04mHZ = 25600sec
.
.
.
... etc
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ON delay time determined by the left hand side capacitor that which
its capacity now is 4mf = 4000uf.
I have build this circuit to turn on a motor for 20 seconds every 6 hours
