CN2299349Y - Controller for preventing fraudulent use of electricity - Google Patents

Abstract

The utility model discloses an electricity theft controller matched with an electricity meter, which comprises a power supply circuit, a current sensor, a signal amplification circuit, a signal comparison circuit, and a switching circuit. The utility model adopts two operational amplifiers and a resistor-capacitor element to form the signal amplification circuit and the signal comparison circuit; the utility model adopts a transistor and two relays as the switching circuit, and effectively prevents the electricity theft action. The utility model has the advantages of simple structure of circuits, few elements, reliable sensitivity, no special requirements for environment and temperature.

Description

Controller for preventing illegal use of electricity

The utility model belongs to the electrical equipment in the electric power system, is specifically related to a kind of anti-electricity-theft device that is used with watt-hour meter.

In electric power system, the user power utilization amount is measured by watt-hour meter, but because the traditional electrical kilsyth basalt exists defective on principle, structure, give electricity filching person with opportunity, cause to exist general stealing electricity phenomenon in the electric power system, the power loss rate is reached more than 30%, not only caused the significant wastage of electric power resource, and accident of power supply and fire are constantly taken place, cause great economic loss.At present, though some anti-electricity-theft devices also occurred, but structurally also perfect not to the utmost, as the circuit complexity, components and parts are many, debugging is complicated, production cost is high, installation and maintenance are difficult, device breaks down back to the user can not normal power supply, power supply department is reluctant to adopt or the like.

The purpose of this utility model is at watt-hour meter live wire the most general in the stealing electricity phenomenon, zero line changing-over, and the stealing mode of ground wire and short circuit meter current coil provides the controller for preventing illegal use of electricity a kind of and simple and convenient that watt-hour meter is used in addition again.

Controller for preventing illegal use of electricity comprises power circuit, current sensor, signal amplification circuit, signal comparator circuit and on-off circuit.The live wire and the zero line of watt-hour meter are passed current sensor in the same way, and the induced voltage signal on the current sensor winding is incorporated into signal amplification circuit, be input to an input end of signal comparator again through amplifying signal, compare with the reference voltage of another input end, when signal reaches certain value, when surpassing reference voltage, comparer output high level, make triode conducting in the on-off circuit, be serially connected in the relay coil energization of transistor emitter, the action of relay can make user load disconnect.

When the user adopts zero line earthing or the stealing of short circuit meter current coil method, the live wire of watt-hour meter and neutral line current must be unequal, like this, can produce induced voltage on the coil of current sensor, controller can move after detecting this signal, the disconnect user load.Can artificially set its breaking time.

Further specify structure of the present utility model below in conjunction with drawings and embodiments.

Fig. 1 is an electrical schematic diagram of the present utility model.

B1 is the 220V/15V/15V power transformer among the figure, its former edge joint 220V civil power, secondary center tap connection circuit reference location GND.B ₁The alternating voltage of secondary output is through diode D ₁, D ₂, D ₃, D ₄Bridge rectifier and capacitor C ₁-C ₆Filtering is by regulator block IC ₁, IC ₂The two 15V DC voltage of output are as the working power of controller.C ₅Positive 15V, C are exported in two ends ₆The negative 15V of two ends output.Current sensor L ₁Be a closed hoop, the live wire of watt-hour meter and zero line pass in the ring in the same way, winding coil one end ground connection on the ring, another termination current-limiting resistance R ₁One end and limiter diode D ₅Anode, D ₆Negative electrode, D ₅Negative electrode and D ₆Plus earth; R ₁The operational amplifier IC of another termination signal amplification circuit ₃Positive input, IC ₃Reverse input end connecting resistance R ₂, R ₃An end, R ₃The other end is through capacitance C ₇Ground connection, R ₂Another termination IC ₃Output terminal and diode D ₇Anode, R ₂, R ₃With IC ₃Constitute R ₂/ R ₃In-phase amplifier doubly.D ₇Negative electrode meets operational amplifier IC in the comparator circuit ₄Positive input, IC ₄Inverse output terminal meet stabilivolt DW ₁Negative electrode and current-limiting resistance R ₄An end, R ₄The other end is connected on dc power anode, DW ₁Plus earth.R ₄, DW ₁And IC ₄The composition reference voltage is DW ₁The comparer of voltage stabilizing value.IC ₄Output termination isolating diode D ₈Anode, D ₈Negative electrode meets timing capacitor C ₈Positive pole and triode BG ₁Base stage, BG ₁Collector connects dc power anode, emitter sending and receiving optical diode LED anode, and the LED negative electrode is succeeded electrical equipment J ₁Coil and sustained diode ₉Negative electrode, J ₁The coil other end and D ₉Plus earth.BG ₁Be switching tube, LED is a pilot lamp, the metering function of having held concurrently.J ₁Normally opened contact be serially connected in dc power anode and relay J ₂Between the coil, J ₂Coil other end ground connection.J ₂Normally closed contact be connected between watt-hour meter 3,4 terminated lines.Two operational amplifier IC ₃, IC ₄7 pin connect dc power anode (+15V), 5 pin connect dc power cathode (15V).

During use, civil power is sent into transformer B ₁Former limit winding, controller is devoted oneself to work.During the normal electricity consumption of user, because live wire equates L with the electric current of zero line ₁There is not signal output, IC ₃Output terminal can signal output not arranged, IC ₄The output terminal output low level, diode D ₈Instead end BG partially ₁Base stage does not have signal voltage, J ₁Can not move.When the user uses zero line earthing or the stealing of short circuit current coil, because zero line and live wire electric current are unequal, L ₁On the winding two ends just induce an alternating signal voltage, through diode D ₅, D ₆Amplitude limit, R ₁Import IC after the current limliting ₃In-phase end carries out homophase and amplifies IC ₃The signal voltage that output terminal output is exaggerated is through diode D ₇Send into IC after detecting negative half-wave ₄Forward end carry out voltage ratio, when the signal voltage of forward end greater than backward end (DW ₁During two ends) reference voltage, IC ₄Output terminal transfers high level to by low level, diode D ₈The positively biased conducting makes BG ₁Capacitor C is given in conducting simultaneously ₈Charging, luminotron LED lights and to relay J ₁Provide electric current, J ₁Adhesive, its normally opened contact J1-1 disconnects, and makes J ₂Action causes the J2-1 that goes here and there at watt-hour meter 3,4 ends to disconnect, and stops the power supply to the stealing user, forces electricity filching person to stop electricity filching behavior.Outage back sensor L ₁Stop signal output, IC ₄Because of losing the comparison signal output low level, diode D ₈Instead end capacitor C partially ₈To BG ₁The relay adhesive is kept in the base stage discharge.Along with C ₈BG is flow through in the reduction of both end voltage ₁The electric current of collection, emitter-base bandgap grading reduces gradually, up to C ₈Terminal voltage is lower than triode BG ₁Forward voltage, BG ₁End relay J ₁Discharge, its contact J1-1 recovers often to open J ₂Discharge, its contact J2-1 closure is recovered the power supply to the user, thereby has finished the strictness control to electricity filching behavior.

The utility model circuit is very simple, and reliable operation can be finished control stealing task under the 170V mains supply.Exchange quiescent dissipation little (1.3W),, environment and temperature are not had specific (special) requirements the stealing signalizing activity sensitivity more than the 20W.

Claims (2)

1, the controller for preventing illegal use of electricity that is used of a kind of and watt-hour meter, it comprises power circuit, current sensor, signal amplification circuit, signal comparator circuit and on-off circuit is characterized in that the live wire of watt-hour meter and zero line are through passing current sensor L in the same way ₁, L ₁On winding one end ground connection, the other end inserts operational amplifier IC in the signal amplification circuit ₃Positive input, IC ₃Reverse input end meets electric cloudy R ₂, R ₃An end, R ₃The other end is through capacitor C ₇Ground connection, IC ₃Output termination R ₂The other end and diode D ₇Anode, D ₇Negative electrode meets comparator circuit operational amplifier IC ₄Positive input, IC ₄Reverse input end connecting resistance R ₄An end and stabilivolt DW ₁Negative electrode, DW ₁Plus earth, IC ₄Output terminating diode D ₈Anode, D ₈Negative electrode meets triode BG in the on-off circuit ₁Base stage and capacitor C ₈Positive pole, C ₈Minus earth, BG ₁Collector connects dc power anode, emitter sending and receiving optical diode LED anode, and the LED negative electrode is succeeded electrical equipment J ₁Coil and diode D ₉Negative electrode, J ₁The coil other end and D ₉Plus earth, relay J ₁Normally open contact J1-1 one termination dc power anode, the other end passes through relay J ₂Coil ground connection, J ₂Normally closed interlock J2-1 be connected between watt-hour meter 3,4 ends.

2, controller for preventing illegal use of electricity according to claim 1 is characterized in that said current sensor L ₁It is a closed hoop.

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