SU1327202A1 - Device for monitoring condition of fuses in parallel circuits - Google Patents

Abstract

The invention relates to devices for searching for electrical devices from emergency currents, in particular to devices for monitoring the status of fuses in powerful thyristor units. The aim of the invention is to improve the reliability by simplifying it. Opening the transistor 1 triggers the relay 6, the closing contact 8 of which puts it on a self-pickup. At the same time, the closing contact 9 of the relay 6 shunts the resistor 4, as a result of which the booster current increases abruptly to a value larger than the opening current. The free contacts of the relay 6 are used in the alarm circuit of a single fuse. By eliminating malfunctions in the monitored device, the proposed device is reset to its original state using the button 10 with an open contact. 1 il. (L

Description

resistor 1.1.1, on the transition the emitter is the base of transistor 1 through the resistor 13.1, the closed block-contact 14.1 of the fuse and the collector’s power supply 5 flows an opening current equal to

Ef

 R,

Where

 -potted 1 E

KZ

- the voltage at the outlet of the collector supply source 5;

R. - Resistor Resistance 13.1. The ratio of the voltages E,

and E

The invention relates to devices for protecting electrical devices from emergency currents, in particular, to devices for monitoring the status of fuses in high-power thyristor units.

The purpose of the invention is to improve the reliability of the device by erd simplifying. 10

The drawing shows a diagram of the device.

The device for monitoring the state of the fuses in parallel circuits contains a transistor 1, a source 2 45 base bias, resistors 3 and 4, a source 5 of the collector power supply, an executive relay 6, a diode 7, closing contacts 8 and 9 of the executive relay 6 and a 10 C button. con tact 20 and thyristors 11.1, 11.2. , 11. Paragraphs. Fuses 12.1, 12.2 ... 12.P, resistors 13.1, 13.2 ...

. 13.P, auxiliary contacts 14.1, 14.2 ... 14-.P of these fuses.25

The transistor 1 is connected to the plus source of the bias source 2, the minus of which is connected via a parallel resistor 4 and pin 9 to the resistor 3 and the input of the transistor 1, which is current. The transistor 1 is closed, the device is connected to the output of the control unit prepared for operation in the second device. Source 2 offset rum mode. Free re contacts: the base is connected in series with the IC; the collector power supply point 5, which is connected via button 10 to the executive relay 6, which through the assembly; main closing contact 8 and through the diode 7 is connected to the outputs of the transistor 1.

When a fuse blows, any block contact closes in any branch, creating a circuit for the input current through the fuse contacts 14.1 ... 14.P, resistors 13.1 ... 13.P, base of transistor 1, source 5.

The device works as follows.

In the initial state, the transistor 1 is locked with a booster current equal to

-HE SL

The points 2 and 5 and the resistances R ,, Kd and Rj of the resistors 3, 4 and 13.1 are chosen in such a way that the transistor 1 is reliably opened, i.e.

otk.1 gtodpi Opening of the transistor 1 causes

relay 6, the closing contact 8 which puts it on self-grip.

At the same time, the closing contact 9 of the relay 6 bypasses the resistor 4, as a result of which the back-up current increases abruptly to

 EU / C

 - SUB. 2 R

35

40

greater than the magnitude of the opening

Le 6 is used in the alarm circuit of a single fuse. When another fuse blows, for example, 12.2, protecting thyristor 11.2, the opening current of transistor 1 increases

I ili- ocrl R3 / 2. case carried

and in case of the need to operate the device with two blown fuses, the circuit parameters, namely sources 2 and 5, the resistances of resistors 3 and 4, 13.1 and 13.2 are selected so that I 1.

50

5TKr.2 SUB. 2

The transistor opens and causes a change in potential on the diode 7, which can be used to further construct the circuit.

Having eliminated the malfunctions in the monitored device, P1), the supplied device is reset to its original state, using the button 10 with the opening contact.

Where

SIGNATURE E.

R, + R,

cm

the voltage at the output of the source 2 base displacement; R, R - resistance of resistors 3

and 4.

Therefore, relay 6 in the collector circuit is de-energized. When a fuse blows, for example 12.1, protecting thyristor 1.1.1, the emitter-transistor 1 base transforms through a resistor 13.1, a closed block contact 14.1 of the fuse and a collector power supply 5 flows through an opening current equal to

Ef

 R,

Where

 -potted 1 E

KZ

- the voltage at the outlet of the collector supply source 5;

R. - Resistor Resistance 13.1. The ratio of the voltages E,

and E

current. Transistor 1 is closed, the device is ready for operation in the second mode. The free contacts of the contactors 2 and 5 and the resistances R ,, Cd and Rj of the resistors 3, 4 and 13.1 are chosen so that the transistor 1 is reliably opened, i.e.

otk.1 gtodpi Opening of the transistor 1 causes

relay 6, the closing contact 8 which puts it on self-grip.

At the same time, the closing contact 9 of the relay 6 bypasses the resistor 4, as a result of which the back-up current increases abruptly to

 EU / C

. Transition is under mode.

 - SUB. 2 R

current. Transistor 1 is closed, the device is prepared for operation in v-mode. Free contacts are larger than the opening

about current. Transistor 1 is closed, the device is ready for operation in the second mode. Free contacts pe5

0

Le 6 is used in the alarm circuit of a single fuse. When another fuse blows, for example, 12.2, protecting thyristor 11.2, the opening current of transistor 1 increases

I ili- ocrl R3 / 2. case carried

and in case of the need to operate the device with two blown fuses, the circuit parameters, namely sources 2 and 5, the resistances of resistors 3 and 4, 13.1 and 13.2 are selected so that I 1.

0

five

5TKr.2 SUB. 2

The transistor opens and causes a change in potential on the diode 7, which can be used to further construct the circuit.

Having eliminated the malfunctions in the monitored device, P1), the supplied device is reset to its original state, using the button 10 with the opening contact.

Formula of invention

Device for monitoring the status of fuses in parallel circuits.

containing an executive relay with the first closing contact, a button with the opening contact, N block contacts of the corresponding fuses, the first terminals of which are connected to the positive terminal of the collector's power source, the base of which is connected through the first and second resistors connected in series to the negative terminal of the bias source the base, the positive terminal of which is connected to the emitter of the transistor and the negative terminal of the collector power source, the second terminals of the auxiliary contacts aniteley via respective resistors which are equal Included Quantity

The block contacts are connected to the base of the transistor, which differs from the fact that, in order to increase the reliability of the device by simplifying it, a diode and a second closing contact of the actuating relay are additionally introduced into it, while the cathode is connected to the collector of the transistor, and its anode connected through the first closing contact of the executive relay to the emitter of the transistor and through the executive relay and a button with a break contact to the positive terminal of the collector power supply, the second closing contact of the executive pe Le connected in parallel to the second resistor.

Claims (1)

Form of the invention A device for monitoring the status of fuses in parallel circuits, comprising an actuating relay with a first make contact, a button with an opening contact, N block contacts of the corresponding fuses, the first terminals of which are connected to the positive terminal of the power source of the transistor collector, the base of which through the first and second resistors connected in series, it is connected to the negative terminal of the base bias source, the positive terminal of which is connected to the emitter the torus and the negative terminal of the collector power supply, the second conclusions of the fuse block contacts through the corresponding resistors, the number of which is equal to the number of block contacts, are connected to the transistor base, characterized in that, in order to increase the reliability of the device by simplifying it, The diode and the second closing contact of the executive relay are additionally introduced into it, while the cathode of the diode is connected to the collector of the transistor, and its anode is connected through the first closing contact of the executive relay to the emitter of the trans stories and through to the Executive relay and a NC contact button with a positive terminal of a collector power supply, a second normally open contact actuating relay is connected in parallel to the second resistor.