• Firing circuit is the simplest method to understand the firing or triggering circuit of SCR.

  • The limited range of firing angle control is from 0˚ to 90˚.

  • The potentiometer setting of variable resistance determines the gate voltage amplitude.

  • This variable resistance increased from small value, firing angle increases because the firing angle is proportional to variable resistance.

  • The half wave power output can be controlled only for 50% in this R firing circuit.

  • Circuit Diagram of R firing circuit

    Figure 1

  • The R firing circuit is shown in Figure 1.

  • The corresponding stimulation waveform is shown in Figure.