Time Delay Relay Schematic
Friday, May 21, 2010 by sms
A time delay relay is a relay that stays on for a certain amount of time once activated. This time delay relay is made up of a simple adjustable timer circuit which controls the actual relay. The time is adjustable from 0 to about 20 seconds with the parts specified. The current capacity of the circuit is only limited by what kind of relay you decide to use.
Time Delay Relay Schematic
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Parts
Part
Total Qty.
Description
Substitutions
R1 1 1 Meg Pot
R2 1 10 K 1/4 Watt Resistor
C1 1 10uf 25V Electrolytic Capacitor
C2 1 0.01uf Ceramic Disc Capacitor
D1,D2 2 1N914 Diodes
U1 1 555 Timer IC
RELAY 1 9V Relay
S1 1 1A 120V SPST Switch
MISC 1 Board, Wire, Socket For U1