RU33468U1 - DEVICE OF CENTRALIZED ARC PROTECTION OF ELECTRICAL INSTALLATIONS - Google Patents

Description

The utility model relates to electrical engineering and can be used to protect complete switchgears (switchgear and switchgear) from short circuits (short circuit), accompanied by an electric arc.

A device for protecting a switchboard from an electric arc short circuit, containing a voltage sensor, the output of which is connected to the input of a single vibrator, a photo sensor connected to the first input of the logical element AND, the output of which is connected to the output organ and the logical element is NOT connected between the output of the single vibrator and the second the input of the logical element And (USSR Author's Certificate No. 773820, class N 02 I / 22. Publ. 23.10.80, Bull. No. 39).

It is also known a device for protecting switching equipment from an electric arc of a short circuit, containing a power source, a photosensor, a pulse shaper and a reacting organ, a memory element made in the form of a transistor and connected in parallel with its base transition resistor, an anti-interference element made in the form of a differentiating RC circuit , a key element and an output transistor with an executive relay (Copyright certificate No. 1302373, class N 02 And 7/22. Publish. 07.04.87. Bull. No. 13).

However, these devices do not make it possible to identify the triggered sensor and thereby determine the place of occurrence of the arc.

Closest to what is proposed in terms of its technical essence is a centralized arc protection device for electrical installations, containing photosensors equipped with a latching circuit, a ribbon cable, a signal processing unit and output organs (Author's certificate No. 2024149, class N 02 N 7/22. Publish. 30.11.94 g. Bull. No. 22).

But this device has limitations on the number of photosensors, due to the capacity of the analog-to-digital converter (ADC), in addition, the simultaneous operation of two or more sensors leads to the appearance of inaccurate information about the origin of the arc. In addition, this device does not allow to quickly obtain information about the place of occurrence of the arc.

The task to which the proposed utility model is directed is the development of an arc protection device for electrical installations that has a sufficient number of sensors for any switchgear with an indication of the operation of each of them and the issuance of information to the front panel of the emergency cell, i.e. improving the accuracy and efficiency of determining the place of occurrence of the arc.

This goal is achieved by the fact that in the device for centralized arc protection of electrical installations of a housing design containing photosensors equipped with a fixing circuit, a loop, a signal processing unit and output organs, LEDs are additionally introduced according to the number of photosensors equipped with an additional output, while the fixing scheme of photosensors is made in the form electronic key anode

The LED is connected to the main negative output of the corresponding photosensor, and the cathode is connected to the additional output of this photosensor.

The introduction of LEDs by the number of photosensors allows you to accurately determine the place of occurrence of the arc of a short circuit.

And the supply of photosensors with an additional output makes it possible to carry the LEDs to the front panel of the cell, i.e. also makes it possible to quickly determine the place of occurrence of a short circuit arc.

The implementation of the locking circuit of the photosensors in the form of an electronic circuit allows you to register using LEDs the fact of the appearance of the arc.

The connection of the anode of the LED to the main negative output of the photosensor, and the cathode to its additional output makes it possible to indicate the location of the arc of the short circuit.

In FIG. 1 schematically shows a centralized arc protection device for electrical installations.

In FIG. 2 is a diagram of a photosensor.

The device for centralized arc protection of electrical installations (Fig. 1) consists of photosensors 1 equipped with a fixing circuit 2 and an additional output 3 ,, of a loop 4, LEDs 5, a signal processing unit 6, and a block of output organs 7. Photosensors 1 connected in parallel to the cable 4, are placed in switch cubicles and at busbars in places of possible occurrence of an electric arc. LEDs 5 are located on the front panel of the cell in which the photosensors are located 1. The loop 4 passes through all the cells and is connected to the signal processing unit 6. The device operates as follows:

When an arc occurs from a short circuit, the light flux, reaching photodiode 8 (Fig. 2), causes a decrease in the resistance of the latter and leads to the operation of the electronic switch 9 (for example, in the form of a single vibrator) and the appearance of current in the loop 4 (Fig. 1). The appearance of current in the loop 4 is perceived by the signal processing unit 6, the alarm signal from which, when an arc occurs, enters the block of output organs 7, which in this case sends a signal to turn off the circuit of the input and section switches.

The appearance of current in the loop 4 (Fig. 1) during the transition of the electronic switch 9 (Fig.2) to the open state leads to the appearance of voltage across the resistor 10 (Fig.2). In parallel to this resistor 10, a resistor 11 is connected, to which an LED 5 is connected (Fig. 1), which detects the appearance of voltage on the resistor 10 (Fig. 2). The glow of the LED 5, located on the front panel of the switch cell, indicates the operation of the corresponding photosensor 1, and, therefore, the occurrence of an arc in the field of view of the photosensor 1.

Thus, the proposed device can improve the accuracy and efficiency of determining the place of occurrence of the arc.

Claims (1)

A centralized arc protection device for electrical installations containing photosensors equipped with a fixing circuit, a loop, a signal processing unit and output organs, characterized in that LEDs are introduced into it according to the number of photosensors equipped with an additional output, while the fixing circuit of the photosensors is made in the form of an electronic key, anode The LED is connected to the main negative output of the corresponding photosensor, and the cathode is connected to the additional output of this photosensor.