CN2057787U

CN2057787U - Multi-functional protective device

Info

Publication number: CN2057787U
Application number: CN 89209633
Authority: CN
Inventors: 夏天伟; 孙鹏; 申承裕
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-10-23
Filing date: 1989-10-23
Publication date: 1990-05-30

Abstract

The utility model relates to a multifunctional electronic protective device which is used for the civil current supply. The utility model is provided with the functions of electrical-leakage protection, electrical-shock protection, current-limiting protection, short circuit protection, over-voltage protection, under-voltage protection, and electric-larceny protection. The utility model adopts a simple and practical sampling circuit, a drive circuit, a tripping controlled circuit and a trip to ensure the reliability in operation. Compared with the present produced multi-function protective device, the protective device of the utility model has the advantages of simple structure, reliable operation, compactness, low cost, multi-protective function, strong breaking capacity, etc. The utility model is an ideal protector for the protection of the civil current supply.

Description

Multi-functional protective device

The utility model belongs to the electrical equipment protective device, has electric leakage, electrical shock protection, current limliting, short-circuit protection, overvoltage, under-voltage protection and anti-stealing electricity function.It is a kind of simple in structure, reliable, multifunctional circuit-protecting device that breaking capacity is high.

In the multifunctional circuit-protecting device of existing production, principle, structure, circuit are complicated, and used element is more, thereby volume is big, cost is high, reliability is low, and maintenance use inconvenience and function are less.Provided a kind of structure in order to address the above problem No. 852057733 patented technologies of Chinese patent bulletin, but there is following several problem in this protective device:

(1). electric shock, electric leakage and overvoltage, overcurrent protection trigger the release action by two controllable silicon SCR 1 and SCR2 respectively, and the element of use is more, cost is high, complex circuit, poor reliability;

(2). in overvoltage crowbar, adopt piezo-resistance dividing potential drop detectable voltage signals, because the dispersiveness of piezo-resistance parameter is bigger, the overvoltage threshold voltage should not be controlled, and influences the performance index of protector;

(3). in overcurrent, short-circuit signal detector, electrochemical capacitor is used for ac circuit, has reduced the useful life of capacitor;

(4). there is not the under voltage protection function.

The purpose of this utility model just provides a kind of simple in structure, circuit is reasonable, cost is low, reliable multifunctional circuit-protecting device.

The utility model is realized by following technical scheme:

It is made up of power supply and dropout control loop, voltage protection loop and current protection loop.Various detection signals all are connected with the one-way SCR control utmost point by certain circuit, when detection signal surpasses trigger voltage, and the controllable silicon conducting, release is threaded off, its break of contact main circuit.

Civil multifunctional protector operation principle is as follows:

Ifs circuit is working properly; then after release closes a floodgate; the output voltage signal in current protection loop and voltage protection loop all is not enough to trigger the controllable silicon SCR conducting; and the resistance value of resistance R 3, R5 and R8 is bigger; so the electric current of trip coil J is very little; release is failure to actuate, the power consumption equipment normal power supply.If personal electric shock, electric leakage, stealing occur or overcurrent occurs and during short trouble; then the voltage output signal in current protection loop is enough to trigger the SCR conducting; trip coil J flows through certain electric current; the release action; cut off major loop, thereby realize electric shock, electric leakage, overcurrent, short-circuit protection and prevent stealing.If supply voltage is too high, surpass given voltage limiting value, then the voltage on the R4 is enough to trigger the controllable silicon SCR action through diode D7, thereby realizes overvoltage protection.If supply voltage is lower than the threshold value of regulation, then the voltage on the R9 is lower, and triode T is near cut-off state, so the collector voltage of T raises, diode D8 is enough to trigger the SCR action, thereby realizes under-voltage protection.

Accompanying drawing is this protector electrical schematic diagram, and wherein 1. is power supply and release control loop, 2. is the voltage protection loop 3. to be the current protection loop.

The concrete structure of the utility model " civil multifunctional protector " is provided by following examples and accompanying drawing:

220 volts of alternating voltages are imported the user through the contact of release J, in trip coil J reader, constitute DC power supply through rectifier diode D1, D2, D3, D4 rectification more simultaneously, use for dropout control loop in the machine and voltage protection loop.Single-phase silicon-controlled SCR and electrochemical capacitor C1 constitute the control circuit of release J action, and capacitor C 1 can prevent interference signal, play the effect of protection silicon controlled simultaneously.Voltage protection loop bag expands overvoltage crowbar and under-voltage protecting circuit, and overvoltage crowbar is by resistance R 3, R4, and electrochemical capacitor C2 and diode D7 form.R3 and R4 constitute resitstance voltage divider, and C2 plays anti-interference effect, and D7 plays the Signal Spacing effect.Under-voltage protecting circuit is by triode T, diode D8, and resistance R 5, R6, R7, R8, R9, electrochemical capacitor C3, C4 and voltage-stabiliser tube Dw form.Wherein R8 and R9 constitute voltage divider, and T, D8, R6, R7 form inverter, and R5, Dw, C3 constitute the stabilized voltage power supply (about 4V) of above-mentioned inverter.Current protecting circuit is made up of electric shock, electric leakage, anti-electricity-theft and overcurrent, short-circuit protection circuit.Wherein electric shock, earth leakage protective and burglar-proof electric circuit are made up of current transformer B1 and diode D6; overcurrent, short-circuit protection circuit are by current transformer B2; resistance R 1, R2 and diode D5 form; the former limit of current transformer B2 and the inlet wire intersecting chain of major loop; secondary is connected with overcurrent, short-circuit protection circuit; R1 and R2 form voltage divider, and D5 and D6 play the Signal Spacing effect.

Compared with the prior art the utility model has following advantage:

1. defencive function is strong. Overvoltage and low-voltage protection can be realized in the voltage protection loop, and electric leakage, overcurrent, short circuit and anti-electricity-theft protection can be realized in the current protection loop;

2. line construction is simple, cost is low, and electrical apparatus release employing wink actuation mechanism is to guarantee the quick acting of protector. Only adopt the single-phase silicon-controlled control that can realize trip coil of low capacity;

3. the voltage protection loop adopts resitstance voltage divider as the detection signal of supply voltage, because partial pressure value is easy to adjust, so that overvoltage and under-voltage threshold voltage are easy to adjust.

In sum; use the utility model multifunctional circuit-protecting device and have multi-protective function; simple in structure; few, the low cost and other advantages of element; the various occasions of particularly suitable folk power supply; in order to electricity theft prevention and electric shock, electric leakage, overcurrent, short circuit, overvoltage and under-voltage protection, the safety of the protection person and equipment.

Claims

1, a kind of high breaking multifunctional circuit-protecting device, its bag expands power supply and dropout control loop, voltage protection loop and current protection loop; Its feature is as follows:

(1). power supply and dropout control loop

A.220V alternating voltage is imported in this machine through trip coil J through the contact input user of release J simultaneously, and the bridge circuit of forming through rectifier diode D1, D2, D3 and D4 is rectified into direct current again, for using in the machine;

B. unidirectional controllable silicon S CR and electrochemical capacitor C1 constitute the release control circuit, and the controllable silicon positive and negative electrode is in series through DC power supply and trip coil;

(2). the voltage protection loop

A. overvoltage crowbar: resistance R 3 and R4 form voltage divider, and the overvoltage detection signal is provided, and through capacitor C 2 filtering, diode D7 is connected to the controllable silicon SCR control utmost point;

B. under-voltage protecting circuit: resistance R 8 and R9 form voltage divider, and under-voltage detection signal is provided, and triode T, resistance R 6 and R7 form inverter, resistance R 5, voltage-stabiliser tube D _wWith the stabilized voltage power supply of electrochemical capacitor C3 formation inverter, the low-voltage signal is connected to the control utmost point of SCR through diode D8;

(3). the current protection loop

A. electric leakage, electrical shock protection and burglar-proof electric circuit are made up of current transformer B1 and diode D6.Above-mentioned detection signal is connected to the SCR control utmost point through diode D6;

B. overcurrent and short-circuit protection circuit are made up of current transformer B2, resistance R 1, R2 and diode D5, and resistance R 1 and R2 form voltage divider, and overcurrent, short-circuit signal are provided, and signal is connected to the control utmost point of SCR through diode D5.

2,, it is characterized in that adopting the action of a low capacity one-way SCR control release, to realize electric shock, electric leakage, overcurrent, short circuit, overvoltage, under-voltage protection and to prevent stealing by the described high breaking multifunctional circuit-protecting device of claim 1..