SU1409996A1 - Device for protecting two-pole supply source against overloads - Google Patents

Abstract

The invention relates to electrical engineering and can be used to power electronic equipment. The purpose of the invention is to expand the functionality of the device. The device contains current-sensing elements in each channel, in parallel to each of which the optocoupler light emitter is connected through a diode. The photodetector of each of the optocouplers is connected to one output through a resistor to the output terminal and through a diode to the terminal of the corresponding channel to connect the actuator of this channel. It is possible to disconnect the load from the power source in case of overload or overvoltage. The introduction of an additional LED into the optocoupler of each of the channels expands; field of application of the device. The element base is expanded — the photoresistor, phototransistor, or photo thyristor can be a photoreceiver of an optocoupler. 1 hp f-ly, 2 ill. Q

Description

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The invention relates to electrical engineering and can be used in power supply devices for electronic equipment.

The purpose of the invention is the expansion of functionality.

FIG. 1 shows an electrical circuit / device with overload protection; FIG. 2 is the same, with protection against overloads and overvoltages.

A device for protection of a two-pole power source against overloads (FIG. 1) contains between terminals 1 and 2 for connecting a power source and terminals 3 and 4 for connecting a load current sensing elements

5 and 6, parallel to each of which a light emitter 9 (Yu) of the optocoupler 11 (12) is connected through a diode 7 (8),

The photodetector 13 (14) of the optocoupler 11 (12) is connected by one output through a resistor 15 (16) to the terminal 1 (2) and through the diode 17 (18) to 19 (20) of the corresponding channel to connect the actuator of this channel. The opposite output of the photodetector 13 (14) is connected via a diode 8 (7) to the output terminal 4 (3) of the opposite channel.

An additional light-emitting diode 21 (22) is introduced into the optocoupler 11 (12) of each channel (FIG. 2), one output of which is connected to terminal 3 (4), and the second through a resistor 23 (24) to a common bus.

In the nominal "1" operation of the power source, the voltage drop across the current-sensing elements 5 and

6 is not enough to turn on optrons 11 and 12. When one of the channels exceeds the threshold value of the fall of a nair on a current-sensitive element 5 (6), the luminosity of the LED 9 (10) increases, the photodetector 13 (14) turns on, and the circuit is closed; resistor 15 (16), photodetector 13 (14), LED 10 (9), terminal 19 (20), photodetector 13 (14) LED 10 (9), terminal 2 (1). The diode 8 (7) shunts together with the diode 10 (9) the current sensing element 6 (5) and with an overload in this channel a current flows through it. . In case of overload in the opposite channel, the diode 8 (7) is biased in the opposite direction and the shutdown current flows completely through the LED 10

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(9), which leads to the inclusion of the photodetector 14 (13), a circuit similar circuit: resistor 16 (15), the photodetector 14 (13), the LED 9 (10).

When the optocoupler 11 (12) is turned on, the current through the LED Yu (9) of the optocouplers 12 (11) of the opposite arm, determined by the resistance of the actuator of this channel connected to the terminals 19 (20), may be insufficient to turn on the LED 10 (9). To increase the reliability and ability of the protection device to operate with various actuators, a resistor 15 (16) and a diode 17 (18) are inserted into the device.,

When the optocoupler 11 (12) is turned on, the operating current of the LED 10 (9) connected in series with the photoreceiver 13 (14) of the opposite channel optocoupler 11 (12) is determined by the total current of the actuating element of the protection of this channel and, accordingly, the resistor 15 (16).

If an overvoltage occurs in one of the channels (Fig. 2), the current in the circuit increases: LED 21 (22), resistor 23 (24), luminosity of LED 21 (22) increases, which leads to the inclusion of photo-receiver 14 (13) of the optocoupler 1 (11) and turn off both source channels.

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To restore normal operation after eliminating the cause of the protection, it is necessary to turn off and then turn on the power source.

Claims (2)

1. Device for protection of a two-pole power source against overloads, containing in each of the two channels a current-sensing element connected between a terminal for connecting the power source and a terminal for connecting the load, an optocoupler consisting of a photodetector and an LED, one output of which is connected with one of the leads of the current-sensing element to the terminal for connecting the power source, the first and second diodes and the terminal for connecting the actuator of the specified power source, characterized in that Expansion functionality, one of the conclusions The photodetector of each channel is connected via an input resistor to a terminal for connecting a power source and through a first diode to a terminal for connecting an actuator of the specified power source, and another photodiode output with a second output of the opposite channel LED through another diode to a different current-sensitive element of the opposite channel. 2. The device according to claim 1, in which, in order to expand the field of application, an additional LED is introduced into the optocoupler of each channel, one output of which is connected through the input of the second resistor to the common bus, and the other to terminal for connecting load. Fig. /