SU955344A1

SU955344A1 - Protection device

Info

Publication number: SU955344A1
Application number: SU813267228A
Authority: SU
Inventors: Евгений Сергеевич Антипов; Александр Николаевич Галкин
Original assignee: Войсковая Часть 11284
Priority date: 1981-03-30
Filing date: 1981-03-30
Publication date: 1982-08-30

Description

Изобретение относитс к устройствам защиты электрических цепей от перегрузок и может быть использовано дл защиты источников питани электротехнических систем от перенапр жени .The invention relates to devices for protecting electrical circuits from overloads and can be used to protect electrical power supply sources from overvoltage.

Известны устройства .цл защиты, содержащие основной и резервный, включенный через диод параллельно основному, предохранители, транзистор , эмиттерно-базовый переход которого подключен параллельно диоду, а коллектор соединен с базой транзистора , в коллекторную цепь которого включен исполнительный элемент 1 .Known devices. Protection, containing the main and backup, connected through a diode in parallel to the main, fuses, the transistor, the emitter-base junction of which is connected in parallel to the diode, and the collector is connected to the base of the transistor, the collector circuit of which includes the actuating element 1.

Недостатком известных устройств вл етс невысока надежность.A disadvantage of the known devices is low reliability.

Наиболее близким к предлагаемому по технической сущности и достигаемому результату вл етс устройство дл защиты, содержащее подключенный своими выводами -соответственно к одной из входных и выходных клемм, первый предохранитель, зашунтированный цепью из последовательно включенных диода и второго предохранител , первый транзистор, подсоединенный эмиттером к аноду диода и коллектором через последовательно соединенные первый и второй резисторы к общейClosest to the proposed technical essence and the achieved result is a device for protection containing connected by its leads - respectively to one of the input and output terminals, the first fuse, shunted by a circuit of a series-connected diode and the second fuse, the first transistor connected by an emitter to the anode diode and collector through serially connected first and second resistors to the common

шине,второй транзистор, подсоединенный своей базой к точке соединени первого и второго резисторов, эмиттером - к общей шине и коллектором к первому зажиму исполнительного элемента, третий резистор, соединенный своим первым выводом с первым выводом четвертого резистора, второй вывод которого подключен к общей шине, и п тый резистор,.подсоединен- « ный первым выводом к катоду диода f.bus, the second transistor connected by its base to the point of connection of the first and second resistors, the emitter to the common bus and collector to the first terminal of the actuating element, the third resistor connected by its first output to the first output of the fourth resistor, the second output of which is connected to the common bus, and a fifth resistor. connected by the first lead to the cathode of the diode f.

Недостатками известного устройства вл ютс значительные потери мощности на транзисторах и отсутствие возможности изменени тока срабатывани в процессе эксплуатации.The disadvantages of the known device are significant power losses on transistors and the inability to change the response current during operation.

Цель изобретени - уменьшение потерь мощности и обеспечение возможности управлени током срабатывани защиты.The purpose of the invention is to reduce power losses and provide the ability to control the current response of the protection.

Claims

The goal is achieved by the fact that the protection device is equipped with a zener diode and a fifth resistor is variable, with the zener diode connected to the base of the first transistor by a vortex and the anode to the engine of the fifth resistor, the second output of which is connected to the diode anode, and the second element is connected via the third resistor to the diode cathode. The drawing shows a circuit diagram of a device for protection. The device for protection contains two 11 predokharniTel 1 and 2, a diode 3, shunted by a variable resistor 4, the slider of which is connected to the base of the first transistor 5 through a zener diode b, resistors 7 and 8, an actuator 9, a base resistor 10, a second transistor 11, a resistor 12 and pins 13 of executive element 9. The device operates as follows. In normal operation, the current flows through fuse 1, and fuse 2 connected to diode 3 is in an idle state. When a fuse 1 (open circuit failure) fails, a current flows through diode 3 and fuse 2, creating a voltage drop across diode 3. The magnitude of the voltage drop across the diode 3 at a load current less than or equal to the rated voltage is insufficient to cause a breakdown of the Zener diode 6. Both transistors 5 and 11 are in the closed state, npvt increasing the load t more than the nominal or failure of the fuse 2 (failure type open circuit) the voltage drop taken from resistor 4 becomes sufficient for the breakdown of Zener diode 6. At the same time, the transistors 5 and 11 jump into a saturated state, which triggers the actuator 9. The actuating element 9 outputs a contact am 13 signal protection is activated. The use of variable resistor 4 and zener diode 6 allows changing the response threshold of the device for protection and reduces the power released by the transistors due to the operation of transistors 5 and 11 in key modes. Ensuring the operation of transistors in key modes allows increasing the reliability of the device for protection, reducing its dimensions and weight. Claim device For protection, connected to its terminals, respectively, to one of the input and output terminals of the first fuse, shunted by a circuit of a series-connected diode and a second fuse, the first transistor connected by an emitter to the anode of the diode and a collector through serially connected first and second resistors to a common bus, the second transistor connected by its base to the point of connection of the first and second resistors, the emitter to the common bus and the collector to the first to the actuator element, the third resistor connected with its first output to the first output of the fourth resistor, the second output of which is connected to the common bus, and the fifth resistor connected by the first output to the cathode of the diode, in order to reduce power losses and. control current operation protection, it is equipped with a zener diode and a fifth resistor is made variable, and the zener diode is connected by its cathode to the base of the first transistor and the anode to the engine of the fifth resistor, the second output of which c connected to the anode of the diode and a second terminal connected to the actuating element via a third resistor to the cathode dieda. Sources of information taken into account in the examination 1. German patent number 2533182, cl. H 02 H 3/04, 1978.

2. Authors certificate USSR 665348, cl. H 01 H 85/30, .1978.