triggering circuit


Posted on Feb 7, 2014

Simple resistor, diode combinations trigger and control SCRs over the full 180 electrical degree range, performing well at commercial temperatures. These types of circuits operate most satisfactorily when SCRs have fairly strong gate sensitivities. Since in a scheme of this type a resistor must supply all of the gate drive required to turn on the


triggering circuit
Click here to download the full size of the above Circuit.

SCR, the less sensitive the gate, the lower the resistance must be, and the greater the power rating. Figure 1 shows a very simple variable resistance half-wave circuit. It provides phase retard from essential zero (SCR full on ) to 90 electrical degrees of the anode voltage wave (SCR half on ). Diode D1 blocks reverse gate voltage on the negative half-cycle of anode supply voltage. It is necessary to rate blocking to at least the peak value of the AC supply voltage and the trigger voltage producing the gate current to fire IGF are in phase. When EAC = Em, at the peak of the AC supply voltage, the SCR can still trigger with the maximum value of resistance between anode and gate.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    SOLAR REVOLVER
    8 LED`s Audio VU Meter
    Ultrasonic switch circuit
    70Mhz Rf Power Amplifier Circuit
    AF counter circuits
    voltage Calculating current in a simple circuit
    Using C-52 EVB for simple robot experiments
    The Audionics CC-2 Amplifier
    The Finder
    Valve/Tube Low Frequency amplifier 30W



    Top