SU1372456A1 - Apparatus for monitoring presence of voltage in three phase mains - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to increase reliability. In the presence of three phases, the LED of the optocoupler 2, powered by the voltage of the first and second phases, controls the photo thyristor of the optocoupler connected in series with the actuator 3 to the voltage of the second and third phases, which ensures the passage of current through the actuator. In the case of an incomplete phase mode - the absence of one of the phases, there is no voltage either in the power supply circuit of the LED, or in the power supply circuit of the actuator, which ensures that the actuator is not included, i.e. active control of the incomplete-phase mode of a three-phase network. 1 il.

Description

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The invention relates to the field of electrical engineering and can be used to protect electrical installations against accidents caused by an incomplete-phase mode of three-phase networks.

The purpose of the invention is to increase reliability.

The drawing shows a diagram of a device controlling the presence of a voltage of a three-phase network.

The device contains a resistor 1, an optocoupler 2, an actuator 3, the first 4 and second 5 diodes, the cathode of the first diode 4 is connected to the first output of resistor 1, the second output of which is intended to be connected to the pole 6 of the first phase of the monitored network, the anode of the first diode 4 is connected An optical diode 2, an anode of an optocoupler 2 LED is connected to the cathode of a photothyristor of an optocoupler 2 and is intended to be connected to the pole 7 of a second phase of the monitored network, the anode phototiristor of an optocoupler 2 is connected to the anode of the second diode 5 and itelnogo member 3, the second terminal of which is connected to the cathode of the second diode 5 and is intended for connection to the pole 8 of the third phase-controlled network.

The device works as follows.

In the presence of voltage at the poles 6-8, the current arising in the circuit of the limiting resistor 1 - the first diode 4 - the LED of the optocoupler 2 caused the -. The luminous flux in the LED of the optocoupler 2. The luminous flux of the LED affects the photothyristor of the optocoupler 2. In this case, the photothyristor of the optocoupler 2 and the actuating element 3 flows a positive current

luperiod, ensuring its operation-controlled network, the anode of the first

the In the absence of a voltage of one of the poles, for example 6, the LED of the optocoupler 2 does not emit light, the photo thyristor of this optocoupler is locked, current does not flow through the actuating element 3. As a result,. Support element 3 cannot work. In the absence of pole 8, the LED of the optocoupler 2 is flowed around the current, but in the circuit the photo thyristor — the actuating element of the current cannot exist. The executive element in this case VNIIPI Order 491/47

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the diode is connected to the cathode by an LED of the optocoupler, the anode of which is connected to the cathode of the photothyristor of the optocoupler and provided with an output for connecting the monitored network to the second phase output for connection to the third phase of the controlled network.

Circulation 649 Subscription

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also can not work. In the absence of pole 7, the current through the LED of the optocoupler cannot pass, because the photo thyristor of this optocoupler is locked. Thus, in all three cases of incomplete-phase mode of a three-phase network, the actuator cannot operate.

From the description of the operation of the device, it can be seen that in the presence of voltage at three poles, the actuating element 3 is triggered, since it flows around the current. The second diode 5 performs the function of a buffer diode.

In the absence of voltage at any of the poles, two or three poles, the actuator 3 does not flow around and cannot operate, which indicates the absence of a three-phase voltage in the controlled network.

Thus, when the full-phase mode of the three-phase network is operated, the actuating element is triggered, in the case of an incomplete phase mode and the complete absence of voltage, the additional element does not work, which indicates that it is possible to control the voltage of the three-phase network by the proposed device.

Claims (1)

Invention Formula A three-phase network voltage monitoring device containing a resistor, an optocoupler and an actuating element, characterized in that, in order to increase reliability, two diodes are additionally introduced into the device, with the cathode of the first diode connected to the first output of the resistor equipped with a second output for connecting to the first phase 0 five the diode is connected to the cathode of the LED of the optocoupler, the anode of which is connected to the cathode of the photothyristor of the optocoupler and provided with an output for connecting to the second phase of the monitored network output for connection to the third phase of the controlled network. Circulation 649 Subscription