Incandescent Yeonsu electronic controller 3

Closing switch S, the power supply positive half cycle, the power by VD1, Rl, VD2 to charge the capacitor C, C at both ends of the electrical pressure gradually increased, but

much lower than the threshold voltage of the zener diode of VD5, VD5 in the off state, can silicon vs control because there is no contact Friends of the current in the off state, then no current flows through the bulb H. When the negative half-cycle alternating current, the current through R2 and VD3 to provide SCR vs negative trigger current, vs opened, there was a half-wave alternating lamp H by preheating. As long as the voltage across capacitor C is less than the regulation value VD5 in an alternating cycle, the current flowing through the lamp H is only half week period, which is the soft-start process of the lamp. Over time, C voltage across the rising, when raised to well over VD5 when regulation value, VD5 conduction, and provide contact pull-up current SCR vs, so in alternating positive half weeks, vs also opened pass, when the soft-start process ends bulb, the bulb H enters full voltage power supply status. Soft start time mainly by the capacitance C of the decision capacitance.

Leave Comment

characters left:

New Circuits