photosensitive II of SCR variable frequency synchronous starter circuit

Published:2011/6/7 0:16:00 Author:John | Keyword: variable frequency synchronous starter | From:SeekIC

2CUD is used for photoelectric control. When it is affected by illumination, the photocurrent occurs to conduct 3DG8C. 3V voltage drop is generated on resistor with resistance of 2KΩ. Therefore, the next individual DG8C is also conducted (saturated). Both ends of 0.01μF capacitor is regarded as short-circuit. And double base tube BT33C stops oscillation and there is no output of line terminal. Where there is no light, the two 3DG8C close. The double-base diode oscillator works, resulting in sharp pulse output waveform. Such would be amplified by 3DK4C to output trigger pulse waveform of the terminal, just as shown in the figure. Partial electrical angle with a pulse output is 140 ° and partial electrical angle with no pulse output is 220 °. This trigger pulse waveform is sent to the SCR inverter.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Power_Supply_Circuit/photosensitive_II_of_SCR_variable_frequency_synchronous_starter_circuit.html

Print this Page | Comments | Reading(3)