CN2590001Y

CN2590001Y - Residual current detecting instrument

Info

Publication number: CN2590001Y
Application number: CN 02261259
Authority: CN
Inventors: 高翔凌
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-11-05
Filing date: 2002-11-05
Publication date: 2003-12-03
Anticipated expiration: 2012-11-05

Abstract

The utility model discloses a residual current detecting instrument. The utility model comprises a working power supply rectification circuit, a zero sequence current transformer ZCT and amplifying circuit, a filtering direction limiting circuit, and a signal transmitting circuit, wherein, the filtering direction limiting circuit and the signal transmitting circuit are connected in parallel with the output terminal of the rectification circuit; the zero sequence current induction detecting and amplifying circuit is connected between the filtering direction limiting circuit and the signal transmitting circuit. When a zero sequence current transformer ZCT detects residual current which exceeds the limited value (which can be arranged between 3 mA to 500 mA as required) in an electric line, signals can be provided for a concentrated metering system by the signal transmitting circuit to display the information of the residual current which exceeds the limited value, so that the department which supplies power can repair the line in time. Therefore, the utility model has a good function repairing effect on electrical leakage circuit breakers, so that the hidden troubles existing in the lines can be discovered in time, and at the same time, the electrical leakage in the lines can not be known as the damage of the electrical leakage circuit breakers by mistake.

Description

The residual current detector

Technical field the utility model relates to a kind of current detecting instrument, specifically a kind of residual current detector that the residual current with electric line is detected of being used for.

Background technology prevents the generation of electric shock accidents for ensureing Electrical Safety, with generally all adopting residual current circuit breaker (be residual current action breaker, be commonly called as electric protective device) to use the function of automatically cutting off of electric line when realizing leaking electricity in the electric line.But, according to national standard, when having only the residual current in the Live wires road to reach specified residue action current standard value, residual current circuit breaker could cut off automatically, and it can not produce any caution or action during less than specified residue action current standard value at residual current, and this moment is with having existed hidden danger or fault in the electric line.In addition, sometimes because of the electricity consumption line electrical leakage, residual current circuit breaker disconnects back user oneself does not always close, at this moment the user often to take for be that residual current circuit breaker has been damaged, and in fact very likely be because of not detecting the residual current of existence, and there is not in time to get rid of the leak current fault in the circuit.

The summary of the invention technical problem to be solved in the utility model be to propose a kind of can be to the residual current detector that can detect automatically during greater than setting value with the residual current in the electric line.

For solving the problems of the technologies described above, residual current detector of the present utility model comprises that working power commutating circuit, zero sequence current mutual inductor ZCT and amplifying return circuit, filtering limit transmit the loop to loop and signal, described filtering limit transmits the output terminal that the loop is connected in described commutating circuit in parallel to loop and signal, and described zero-sequence current inductance detects and amplifying return circuit is connected described filtering limit between loop and signal transmission loop.

Above-mentioned residual current detector, described zero sequence current mutual inductor ZCT and amplifying return circuit are by current-limiting resistance R2, triode amplifier, the zero-sequence current telefault, capacitor C 2 is formed, described filtering limit is composed in series by diode D5 and capacitor C 1 to the loop, it is by current-limiting resistance R1 that described signal transmits the loop, optocoupler follower and controllable silicon are composed in series, described current-limiting resistance R2 connects the collector of triode amplifier, be connected between the base stage and emitter of triode amplifier after described zero-sequence current telefault and capacitor C 2 parallel connections, the emitter of described triode amplifier extremely links to each other with the control of described controllable silicon SCR.

Above-mentioned residual current detector, the two ends of capacitor C 2 are parallel with the residual current acting setting value that is composed in series by capacitor C 3 and K switch and adjust the loop in the telefault of described zero sequence current mutual inductor ZCT and the amplifying return circuit.

Above-mentioned residual current detector, serial connection one caution device between current-limiting resistance R1 in described signal transmission loop and optocoupler follower.

Owing to adopted above-mentioned line connection, to pass zero sequence current mutual inductor ZCT with electric line during use, the operating voltage of the utility model residual current detector is loaded on rectification goes the same way, after D1-D4 rectification and resistance R 1, R2 current limliting, offers controllable silicon and triode amplifier.When in zero sequence current mutual inductor ZCT detects with electric line, having residual current above limit value (can set between the 3mA to 500mA as required) to exist, the signal amplification is sent to the silicon controlled control utmost point, make the controllable silicon conducting, thereby provide signal to automatic meter reading system by the optocoupler follower, the information that residual current exceeds standard in the display circuit, power supply department just can in time be safeguarded line fault.Therefore, for residual current circuit breaker, it can play good function and remedy effect, so that find the hidden danger that exists in the circuit in time, early.Simultaneously, also the leak current fault that exists in the circuit can not thought by mistake the damage of residual current circuit breaker.Adjust the effect that the loop can be played selection, be adjusted the residual current acting setting value size of required detection by the residual current acting setting value that capacitor C 3 and K switch are composed in series, during as the K switch closure, detectable residual current acting setting value is 10mA, and when K switch is opened, can detected residual current limit value be 15mA, adaptability be strong.The caution device that between current-limiting resistance R1 and optocoupler follower, is connected in series (as light emitting diode, buzzer, acousto-optic integrated circuit, speech IC etc.), can play alarm suggesting effect to the user, so that make user oneself find that early it is with the problem that exists in the electric line, investigate thoroughly reason, remove a hidden danger.

Description of drawings is described in further detail the utility model below in conjunction with embodiment and accompanying drawing.

Fig. 1 is the circuit diagram of the utility model residual current detector.

Embodiment as shown in the figure, the residual current detector comprises that working power commutating circuit, zero sequence current mutual inductor ZCT and amplifying return circuit, residual current acting setting value are adjusted the loop, the filtering limit transmits the loop to loop and signal, and the operating voltage of detector is for exchanging 6V.The filtering limit is composed in series by diode D5 and capacitor C 1 to the loop, signal transmits the loop and is composed in series by current-limiting resistance R1, light emitting diode LCD, optocoupler follower and controllable silicon SCR, and signal transmits the loop and the output terminal that is connected in commutating circuit to the loop in parallel is limit in filtering.Zero sequence current mutual inductor ZCT and amplifying return circuit are made up of current-limiting resistance R2, triode amplifier BG, zero sequence current mutual inductor ZCT, capacitor C 2, current-limiting resistance R2 one end links to each other with filtering limit negative electrode of diode D5 in the loop, the collector of another termination triode BG, be connected between the base stage and emitter of triode amplifier BG after zero sequence current mutual inductor ZCT and capacitor C 2 parallel connections, the emitter of triode amplifier BG extremely links to each other with the control of controllable silicon SCR.The residual current acting setting value is adjusted the loop and is composed in series by capacitor C 3 and K switch, and it is connected in parallel on the two ends of capacitor C 2.

In the utility model, optocoupler follower also other components and parts with identical function such as available relay substitutes.Signal transmits in the loop also can only adopt light emitting diode LCD without the optocoupler follower, so only produces the warning effect to user oneself.The various modes of connection such as that residual current detector of the present utility model can be applicable to simultaneously is single-phase, phase three-wire three or three-phase and four-line.

Claims

1, residual current detector, it is characterized in that, it comprises that working power commutating circuit, zero sequence current mutual inductor ZCT and amplifying return circuit, filtering limit transmit the loop to loop and signal, described filtering limit transmits the output terminal that the loop is connected in described commutating circuit in parallel to loop and signal, and described zero-sequence current inductance detects and amplifying return circuit is connected described filtering limit between loop and signal transmission loop.

2, residual current detector as claimed in claim 1, it is characterized in that, described zero sequence current mutual inductor ZCT and amplifying return circuit are by current-limiting resistance R2, triode amplifier, the zero-sequence current telefault, capacitor C 2 is formed, described filtering limit is composed in series by diode D5 and capacitor C 1 to the loop, it is by current-limiting resistance R1 that described signal transmits the loop, optocoupler follower and controllable silicon are composed in series, described current-limiting resistance R2 connects the collector of triode amplifier, be connected between the base stage and emitter of triode amplifier after described zero-sequence current telefault and capacitor C 2 parallel connections, the emitter of described triode amplifier extremely links to each other with the control of described controllable silicon SCR.

3, residual current detector as claimed in claim 2, it is characterized in that the two ends of capacitor C 2 are parallel with the residual current acting setting value that is composed in series by capacitor C 3 and K switch and adjust the loop in the telefault of described zero sequence current mutual inductor ZCT and the amplifying return circuit.

4, as claim 2 or 3 described residual current detectors, it is characterized in that serial connection one caution device between current-limiting resistance R1 in described signal transmission loop and optocoupler follower.