CN2100628U

CN2100628U - False wiring protective device for watt-hour meters

Info

Publication number: CN2100628U
Application number: CN 91221515
Authority: CN
Inventors: 秦传勇
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-08-14
Filing date: 1991-08-14
Publication date: 1992-04-01

Abstract

The utility model relates to a false wiring protective device for watt-hour meters. The utility model is composed of a detection circuit which samples the voltage and current signals in a single phase meter and carries out the shaping and comparison to the voltage and current signals, and an action executive circuit which carries out counting, tripping operation and power cut off operation. In the normal wiring connection, the voltage and the current of the same watt-hour meter come from the same phase wire; in the false wiring connection, the voltage and the current of the same watt-hour meter do not come from the same phase wire, and the phase difference appears; thus, after comparison, the action executive circuit works to cut off power when the phase difference appears. The damage of the watt-hour meter, or other accidents or the electric larceny phenomenon because of false wiring connection can be avoided. Meanwhile, the utility model can also detect the phase interruption and the short circuit of a back phase wire and the disconnection fault of zero lines, and cut off the power.

Description

False wiring protective device for watt-hour meters

The utility model relates to the protective device that a kind of watt-hour meter prevents error connection, and particularly the three-phase power watt-hour meter prevents the monitoring and protecting device of error connection.

At present, the electric power watt-hour meter is because error connection takes place is that the voltage and current coil of ammeter is not the same phase line of getting, and potential winding is broken, the watt-hour meter cisco unity malfunction, even burn or cause that the phenomenon of fire happens occasionally, simultaneously, more the someone is for making the watt-hour meter error connection, so that watt-hour meter slow-speed or reversing come stealing, had a strong impact on normal power supply, the hidden danger that causes the accident especially.

The purpose of this utility model is exactly to provide a kind of protective device that prevents watt-hour meter generation error connection in order to design, and when finding error connection, stops power supply, and has the monitoring and protecting device that can power after counting, warning, the artificial removing.

The utility model is achieved in that by detecting loop and action circuit two large divisions to be formed, detect the loop and take out that the signal of potential winding and current coil compares in each single-phase table after shaping and pulse waveform compression, voltage, the electric current of the normal same table of wiring should be taken from same phase line, then electric current, voltage phase place after shaping is identical, detect loop output low level signal, action circuit is failure to actuate; Otherwise, during error connection, voltage in the same table, electric current are not to take from same phase line, then phase phasic difference 120 degree or 240 are spent, after shaping, compression, and the impulse phase difference, detect loop output high level signal through relatively making, make action circuit action, stop power supply, and metering number or report to the police by telemechanical.

The utility model has the advantages that but fast detecting goes out electric power watt-hour meter error connection, and can carry out corresponding the power failure, the counting action, avoid error connection to cause burning table or accident, and artificially error connection carries out the key electricity, also can monitor the phase failure, short circuit, neutral line break simultaneously, and carries out action.

Accompanying drawing 1, the wiring of electric power watt-hour meter connects the net synoptic diagram.

Accompanying drawing 2, watt-hour meter prevent error connection protective device block scheme.

Accompanying drawing 3, watt-hour meter prevent error connection protective device wiring schematic diagram.

Three of the present utility model are detected loops and are connected to each single-phase table, and the mode in its composition and connection and the access table is identical, below are that example is described mutually with one.

Describe the concrete structure of the present utility model and the course of work in detail below in conjunction with accompanying drawing.[detecting the loop is example with one mutually].

The utility model is by forming the voltage of each single-phase watt-hour meter, detection loop and the execution counting that current sampling carries out shaping, comparison and the action execution loop that cuts off the power supply of tripping, and the output signal in detection loop is as the input signal in action execution loop; Detect the loop and comprise voltage sampling shaping branch road, current sampling shaping branch road and comparison branch road.

Route high-low pressure isolating transformer B, resistance R are propped up in the voltage sampling shaping ₁～R ₃Execute special not gate G ₁, G ₂, electric capacity D ₁Form, the former limit of B termination Z point of the same name, non-same polarity connects the F point, pays limit non-same polarity ground connection, the end of the same name R that connects successively ₁, G ₂, R ₂, C ₁And G ₂R ₃One termination working power VDD, the other end and C ₁Be connected in G ₂Input end, G ₂Output meet G in the comparison branch road ₃An input end.

The route resistance R is propped up in the current sampling shaping ₆～R ₁₃, capacitor C ₃, operational amplifier IC ₁IC ₂With execute special not gate G ₅Form R ₆Termination D point, one termination IC ₁Inverting input R ₇, R ₁₀Be respectively IC ₁, IC ₂The defeated termination earth resistance of homophase, IC ₁Output through R ₉Meet IC ₂Inverting input, R ₈, R ₁₁Be IC ₁, IC ₂Negative feedback resistor, IC ₂Output series connection R ₁₂, C ₂The R of a termination working power VDD in parallel again ₁₃After be connected to G ₅Input end, G ₅Output be connected to G in the comparison branch road ₃Another input end.

Relatively prop up route and execute special not gate G ₃, monostable G ₄, capacitor C ₂, resistance R ₄, R ₅With diode D ₁Form G ₃Output terminal series connection G ₄, R ₅And D ₁, C ₂And R ₄Form G ₄Delay circuit, R ₄A termination working power VDD, D ₁Output be connected to action and carry out BG in the loop ₁Base stage as input signal.

Action is carried out the loop by triode BG ₁, BG ₂, diode D ₂, resistance R ₁₄R ₁₅, relay J C ₁, JC ₂Sum counter W forms, and K is a hand switch among the figure, J ₁₁, J ₁₂Be JC ₁Normally opened contact, JX is a self-holding contact, J ₂₁, J ₂₂, J ₂₃Be JC ₂Normally closed contact, be serially connected with in the three-phase power line BG ₁, BG ₂Grounded emitter, BG ₁Collector respectively through R ₁₄Meet VDD and through R ₁₅Meet BG ₂Base stage, J ₁With D ₂Be connected to BG after the parallel connection ₂Collector and VDD between J ₁₁Be serially connected with the W loop, J ₁₂Be connected in series K after the JX parallel connection and be connected to JC ₂In the loop.

When using the utility model, three identical detection loops are inserted in three single-phase tables by legend respectively, and its output all is connected to action and carries out BG in the loop ₁Base stage, below be the example analysis mutually with C in the accompanying drawing.

Wiring just often, promptly the voltage of same single-phase table, electric current are taken from same phase line, then voltage is through B step-down and G ₁Shaping, C ₁R ₃And G ₃Waveform compression, G ₃Export the square wave burst pulse corresponding with power frequency, electric current is through IC ₁IC ₂Shaping and, C ₃, R ₁₃With G ₅After the compression, the electric current power frequency burst pulse of output and voltage burst pulse homophase, the two is input to G ₄Make G ₄The pulse of output power frequency is through G ₅And C ₂, R ₁₄After the delay, G ₅The output noble potential, D ₁Conducting, BG ₁Conducting, BG ₁Current collection is electronegative potential very, BG ₂End, then JC ₁Be failure to actuate J ₁₁, J ₁₁Be the beginning, W, JX, JC ₂Be failure to actuate J ₂₁, J ₂₂, J ₂₃Closure guarantees normal power supply; Otherwise, when error connection occurring in arbitrary table mutually, be that voltage, electric current in the same table is not when taking from same phase line, phase differential is 120 degree or 240 degree, voltage after shaping and waveform compression, electric current power frequency burst pulse be homophase [because waveform compression not, best boil down to 1/3rd, also unlikely burst pulse to occur overlapping], G then ₃To export electronegative potential, G ₅Also import electronegative potential, then D ₁, BG ₁End BG ₁Collector is BG ₂Base stage is a noble potential, BG ₂Conducting, JC ₁Action, J ₁₁, J ₁₂Adhesive, W counts, JC ₂Also owing to the self-sustaining effect of JX, one works as J in action ₁₂Adhesive will guarantee JC ₂In have electric current to pass through, J ₂₁, J ₂₂, J ₂₃Action disconnects and keeps off-state, stops power supply, and manually removes for pressing K up to the people, could power.

Because voltage signal is to take from phase voltage, because when phase line broken string, short circuit or heavy line broken string occurring, voltage signal all will disappear, analyze equally during the same error connection, detect the loop all with output low level, action execution loop is moved.

Claims

1, a kind of watt-hour meter prevents the error connection protective device, it is characterized in that carrying out shaping by to the voltage of each single-phase table, current signal sampling, and detection loop relatively and counting, and carry out action that tripping operation has a power failure and carry out the loop and form.

2, device as claimed in claim 1 is characterized in that described detection loop comprises voltage sampling shaping branch road, current sampling shaping branch road and comparison branch road.

3, device as claimed in claim 1 or 2 is characterized in that described voltage sampling shaping props up route B, R ₁～R ₃, G ₁, G ₂, C ₁Form, wherein between the former edge joint zero line and phase line of B, the Fu Bianyi of B holds ground connection, the other end R that connects successively ₁, G ₁, R ₂C ₂Back and the R that is connected to VDD ₃Be connected in G ₂Input end.

4, device as claimed in claim 1 or 2 is characterized in that described current sampling shaping props up route R ₆～R ₁₃, C ₃, IC ₁, IC ₂, G ₅Form, wherein, R ₆Meet IC ₁Inverting input, IC ₁Output through R ₉Meet IC ₂Inverting input, R ₃, R ₁₁And R ₇, R ₁₀Be respectively IC ₁, IC ₂In-phase input end stake resistance and negative feedback resistor, IC ₂Output terminal series connection R ₁₂, C ₃Back and the R that is connected to VDD ₁₃Be connected in G ₅Input end.

5, device as claimed in claim 1 or 2 is characterized in that the described route G that relatively props up ₃, G ₄, C ₂, R ₄, R ₅And D ₁Form, wherein G ₃Two input ends meet G respectively ₂, G ₃Output terminal, G ₃The output terminal G that connects successively ₄, R ₅, D ₁, R ₄And C ₂Form G ₄Delay circuit, R ₄Another termination VDD.

6, device as claimed in claim 1 is characterized in that described action execution loop is by BG ₁, BG ₂, D ₂, R ₁₄, R ₁₄, JC ₁, JC ₂, W, JX, K form, wherein, BG ₁Base stage be connected to and detect D in the loop ₁Output terminal, BG ₁, BG ₂Grounded emitter, BG ₁Collector respectively through R ₁₄, R ₁₅Meet VDD and BG ₂Base stage, D ₂With J ₁Be connected to BG after the parallel connection ₂Collector and VDD between, J ₁₁Be serially connected with in the W loop J ₁₂Be connected in series K after the JX parallel connection and be connected to JC ₂J in the loop ₂₁, J ₂₂, J ₂₃Be connected in the triple-phase line.