This circuit can be used to time delay for the load, To be connected to the relay output to run after a specified time. Which during this time. Can be adjusted by changing the R1 and / or C1. The current of circuit is limited by type of relay that use.
Figure 1 Time delay for relay using CD4011
Calculate the discharge time delay Can be calculated by the equation
T = R1 x C1 x 0.85
T is the period of the delay is in seconds.
R1 is the resistance in ohms.
C1 is the capacitance is measured in uF.
The switch-S1 NPN type transistor may will used instead. Therefore, the circuit can be used to trigger signal from a computer or other circuit. If you want to apply to a higher voltage relays. Just need to add the output transistors. To be able to load more.
How to builds
This project is not used many components so can assemble on the universal PCB board. Then, the wiring and various components can view of the example in Figure 2 be carefull for the polarity of the electrolytic capacitors and Pin of the IC1 correctly.
Figure 2 The components layout of this circuit.
R1______See text __________1 pcs.
C1______See text___________1 pcs.
IC1______CD4011 Quad 2-Input NOR Buffered B Series Gate
D1______1N914 or 1N4148 _____Silicon diode _____1 ???
RL1______Relay 6V_______1 pcs.