Contact Us

Shenzhen Cian Electronics Co.,Ltd

Address: B Building, Weixin Industrial Park, ShiTouShan Industrial Zone, ShiYan Town, Baoan District, Shenzhen City, China

Tel: +86-755-29953144

M/P: +8613008800940


Door Trigger Relay Cut-off On-off

Door Trigger Relay Cut-off On-off

Door trigger relay cut-off On-off

Product Details

Door trigger relay cut-off On-off

There is a door in the power switch. When the power is turned on, a door shuts off the power. Then what is the door? Some switch power supplies use thyristors, and some use switch tubes. These two components have similar performance. The pulse signal is applied to the base and the (switch) control electrode (SCR) to complete the turn-on and turn-off. The pulse signal arrives at the half cycle, the voltage on the control electrode rises, and the switch or the thyristor is turned on. Conduction, by the 220v rectified, filtered output 300v voltage on, through the switch transformer to the secondary, and then through the transformer ratio to increase or decrease the voltage for each circuit work. When the oscillation pulse arrives in the negative half cycle, the voltage of the base of the power supply adjustment tube or the control electrode of the thyristor is lower than the original setting voltage, the power supply adjustment tube is cut off, the 300V power supply is turned off, and the secondary voltage of the switching transformer is not applied. At this time, each circuit The required operating voltage is maintained by the discharge of the secondary local smoothing filter capacitor. Until the next half-cycle signal of the next pulse arrives, repeat the previous process. This switching transformer is called a high frequency transformer because his operating frequency is higher than 50 Hz. Then how to get the pulse of the switch or thyristor to be obtained, which requires an oscillation circuit to generate, we know that the transistor has a characteristic, that is, the base to emitter voltage is 0.65-0.7v is amplifying state, 0.7v The above is the saturated conduction state, -0.1v- -0.3v works in the oscillating state, then after the working point is adjusted well, the negative pressure is generated by the deep negative feedback, so that the oscillating tube starts to vibrate, the frequency of the oscillating tube It is determined by the length of charge and discharge of the capacitor on the base. The high output pulse amplitude of the oscillation frequency is large, and vice versa, which determines the output voltage of the power supply adjustment tube. Then how to regulate the voltage of the secondary output of the transformer is generally on the switching transformer, single winding a set of coils, after the voltage obtained at the upper end is rectified and filtered, as a reference voltage, and then through the optocoupler, the reference The voltage returns to the base of the oscillating tube to adjust the level of the oscillating frequency. If the secondary voltage of the transformer rises, the output voltage of the sampling coil also rises, and the positive feedback voltage obtained by the optocoupler also increases. This voltage is added. On the base of the oscillating tube, the oscillation frequency is reduced, which stabilizes the stability of the secondary output voltage

Hot Tags: door trigger relay cut-off on-off, China, manufacturers, suppliers, factory, customized, bulk, discount, low price, in stock, free sample
Related Products