Simple 24V Lamp Flasher Circuit using Transistors

Simple 24V Lamp Flasher Circuit using Transistors makes 24V lamps blink back and forth with non stop.

It uses transistors to turn two lamps ON and OFF one by one like astable multivibrator.

This circuit is good for signal use like warning or decoration lights with steady blink.

We must use 24V DC power to run this circuit.

Circuit Working:

This circuit is called astable multivibrator and it uses transistors to make lamps blink back and forth nonstop.

When transistor Q1 is ON, lamp L2 lights up and lamp L1 goes OFF.

Capacitor C1 charges through resistor R1.

When C1 voltage is high then it turns ON Q2 and turns OFF Q1.

Now lamp L1 in ON and lamp L2 is OFF.

Then same thing with capacitor C2 and resistor R2.

Lamps keep blinking one after another forever.

Blink speed change by values of C1, C2, R1, R2 because they control capacitor charge time.

Formula for ON-OFF time:

T = 1.38 × R × C

Here

T = 1.38 × 68,000 × 10 × 10⁻⁶

T = 0.9384 = 1 second

So lamps blink alternately every 1 second.

To build a Simple 24V Lamp Flasher Circuit using Transistors following steps are required to be followed:

Assemble parts as per circuit diagram above.
Connect collector of Q1 to one side of L1 and collector of Q2 to one side of L2.
Other side of L1 and L2 goes to +24V supply.
Base of Q1 goes to one end of R1 and base of Q2 go to one end of R2 and other ends of R1, R2 go to +24V.
Emitters of Q1 and Q2 go to circuit GND.
Connect C1 between R1 and L1 side and C2 between R2 and L2 side.

This Simple 24V Lamp Flasher Circuit using Transistors is simple and works well for warning lights, emergency signals or for decoration.

We can change R or C to adjust flash speed.

The 2N3055 transistors can handle high current for bright lamps.