SU1446682A1 - Automatic switch of mains voltage - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to increase reliability by eliminating the short-term occurrence of increased voltage on the transformer windings. When the device is turned on, an overvoltage occurs in the network through the thyristor control circuit 8. The thyristor 8 shunts the relay 3 winding. through the thyristor B control circuit does not flow, and it is closed. After charging the capacitor 4, the relay 3 triggers, and its contacts 2 switch off the primary windings of the transformer 1, setting the required transformation ratio. The goal is achieved due to an additional increase in the activation time of the relay. 1 il. b SL

Description

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The invention relates to electrical engineering and can be used in power supply devices, where appliance damage can occur if it is mistakenly turned on and a non-conforming voltage.

The purpose of the invention is to increase reliability by eliminating the short-term occurrence of a higher voltage on the windings of a transformer,

The drawing shows a circuit diagram of a switch.

The switch consists of a transformer 1, the primary winding of which is 5 transformations, has two sections and three inputs, two of which are connected to one of the input terminals through the switching contact 2, and the third to the other. A parallel input voltage of 20 voltages containing a transtabilron 9 reaches a stabilization level and the current through the thyristor control circuit 8 does not flow. Thyristor 8 is closed. After a certain period of time, which is required for charging the capacitor 6 to the tripping voltage of the relay 3, the relay 3 triggers and the switching contacts 2 switches the taps of the primary winding of the transformer 1, connecting all turns of this winding to the mains and thus setting the necessary factor

Claims (1)

Invention Formula transformations, the automatic switch of the network voltage containing the transtabilron 9 reaches the stabilization level and the current through the thyristor control circuit 8 does not flow. Thyristor 8 is closed. After a certain period of time, which is required for charging the capacitor 6 to the tripping voltage of the relay 3, the relay 3 triggers and the switching contacts 2 switches the taps of the primary winding of the transformer 1, connecting all turns of this winding to the mains and thus setting the necessary factor transformation, - Automatic mains voltage switch containing the trans formula of the invention a circuit is connected to the terminals of resistor, resistor 4, diode 5 and relay 3 winding, in parallel with which is connected capacitor 6 and key element 7, consisting of thyristor 8, between control-25 cut switching contacts of relay - with the connecting electrode and the cathode of which included a chain of series-connected Zener diode 9 and the limiting resistor 10. The switch works as follows. When the power supply is turned on, the Zener diode 9 comes into operation at a voltage of 220 V and a current appears through the thyristor control circuit 8. Through the flow of the control current, the thyristor 8 opens and shunts the winding of the relay 3, which with its contacts 2 supplies power on the primary winding of the transformer 1, When the power supply is turned on, the voltage of 127 V is a transformer, the primary winding of which has three outputs, one of which is connected to the first output for connecting the network, and the other two five 0 the second one for connecting the network, the key element on the thyristor, the control electrode of which is connected to one of the power terminals of the thyristor through a stabilizer and a limiting resistor, a rectifier and a relay coil in parallel with which a capacitor is connected, in order to improve short-term voltage on the windings of the transformer, the relay winding through the rectifier and the inserted resistor is connected to the terminals for connecting the network, and parallel to the winding of the relay yuchen key element.