CN2030726U - Electricity-stealing defencing device for three-pole electric meter - Google Patents

Abstract

The utility model relates to an electricity-stealing preventing device for three-phase electric meter. The electricity-stealing preventing device for three-phase electric meter utilizes two three-phase current voltage converters whose electromagnetic properties are identical with a parameter to respectively connect with an endpoint to be protected and the line-out end of the current coil so as to form a balance electric bridge; the electric bridge is balanceable during normal power consumption; when various behaviors of electricity stealing occur, the balance electric bridge is destroyed; voltage taken out from the diagonal of the electric bridge is used to trigger a controlled silicon so as to cause the controlled silicon to turn on and to drive an actuating element to cut off the electric source of the users who steal electricity. The utility model hardly consumes power and has no effect on normal measuring of the electric meter.

Description

A kind of device that prevents that three-phase supply is stolen

The utility model is the device that prevents that about a kind of three-phase supply is stolen.

Because the present power tense of China, the electricity filching behavior without the ammeter metering has taken place in some places and unit, and is on the rise.This device prevents the enforcement of electricity filching behavior technically, and when electricity filching behavior took place, this device was implemented outage to it immediately.

" the anti-electricity-theft and electric protective device of watt-hour meter " of filing an application on June 8th, 1987 is made of a current transformer and sensitive electromagnetic actuator, to the stealing and the power-off protection of having got an electric shock of the junction style that directly advances watt-hour meter.But can not shield, and technology and accuracy requirement height to the stealing mode before the watt-hour meter.In addition, up to the present still there is not a kind of three phase watt-hour meter anti-electricity-theft device.

The utility model purpose provide a kind of to three-phase three-wire system watt-hour meter or the various technical stealing of the watt-hour meter of three-phase four-wire system implement power-off protection; can not only be to various stealing modes behind the three phase watt-hour meter table, and the various stealing modes before the watt-hour meter inlet wire are implemented power-off protection (protection domain may extend into arbitrary place before the table).This device also has electric lock mechanism, private is opened the electricity filching behavior of watt-hour meter and line box and implements power-off protection, and this device adopts universal component, and wider accommodation is arranged, and cost is lower.

The technical measures that adopt: one is respectively to adorn a three-phase current that electromagnetic performance is identical with electric parameter at the end points of the line segment that will protect with the power outlet end of three phase watt-hour meter---electric pressure converter (being called for short " converter " down).This converter A, a B, C three-phase adopt and do not wait circle, direct puncture formula, are connected into balanced bridge between two converters.

Another technical measures that adopt are: its topworks is mainly by isolating transformer, bidirectional triode thyristor, one-way SCR, and executive component is as relay, contactor, compositions such as air switch.As everyone knows, the silicon controlled conducting needs a synchronous triggering voltage.But various stealing mode, the output voltage phase place is different, causes the controllable silicon that is connected on a certain stationary phase can not be synchronous.Thereby make the protection failure, this topworks can make various stealing mode all can make the reliable conducting of controllable silicon.

Between converter 1 and 2 arbitrary place show the stealing of cross-over connection more the time (causing ammeter stall or slow-speed), this device all can move, as take off the plug of fuse block 7,8, between a, a ' a of fuse block 7 " and the d of fuse block, d ' d ", use the lead short circuit respectively.This moment converter 2 no currents, the electric current that converter 1 passes through is 2

A+

B+ C.Because the three-phase A.C. current is

A+

B+

In fact C, converter by electric current are

A, this moment on the secondary coil of converter 1, induce electromotive force, isolating transformer T's is primary and secondary, induce one with The corresponding voltage of A electric current, through diode D rectification, capacitor C is level and smooth, makes bidirectional triode thyristor 4 obtain trigger voltage and conducting, at R ₃The trigger voltage of the cathode and anode synchronised of last generation and one-way SCR 6,5 actions of one-way SCR 6 conducting executive components are cut off the electricity supply, and treat that the power supply personnel come on-the-spot involution to send.

Arbitrary place between converter 1,2 connects the load stealing between the relatively arbitrary or two-phase or connect the stealing mode of threephase load on three-phase, all can cut off the power supply.As the stealing over the ground of B phase X point, establish electric current and be X, the electric current that this moment, converter 1,2 passed through is respectively 2 A+ B+

C+ X, 2

A+ B+ C.Bridge balance destroys, topworks's action outage.

Current coil turnover line to each phase of watt-hour meter exchanges, make the stealing mode of watt-hour meter reversing or slow-speed, all can move, take off the plug of fuse block 7,8,, connect with lead as at the C end of a of fuse block 7 end with fuse block 8, the b end of fuse block 7 and the d end of fuse block 8, connect with lead, make the A phase current of converter 2 anti-phase, the electric current of converter 1 is 2 A+ B+

C, the electric current of converter 2 are 2

A+

B+

C, difference is 2

A+

B+

C-(2

A)- B- C=4 A.Bridge balance destroys, topworks's action outage.

The utility model is opened the various electricity filching behaviors (as take off that voltage is buckled, the short circuit current coil, move and adjust magnet etc.) of watt-hour meter and terminal box to private.Drive ammeter and terminal box must be cut off when private, the converter secondary that passes the seal screw hole 9 of table lid and connector cover is connected lead, bridge balance destruction, and topworks moves, and has so just constituted electric lock mechanism.

The utility model adopts watt-hour meter junction box to advance the converter 2 that wire hole presses this device in structure with installing.Advance a sealed rubber packing ring is installed between the wire hole at converter 2 and watt-hour meter, like this, both improved the seal degree of converter 2 and watt-hour meter, prevented to advance the stealing mode of direct short circuit current coil on the wire hole again at watt-hour meter.

A watt-hour meter of joining 25A of this making, its electric current---electric pressure converter cross section 10 * 25mm ²" return " type ordinary silicon steel disc, a three-phase direct puncture, A is two circles mutually, each circle of B, C, line footpath φ 3.5mm stranded conductor, the secondary coil number of turn is 820 circles, line footpath φ 0.2.Isolating transformer T adopts E sections stamen, and the cross section is 6 * 10mm ²Elementary with line footpath φ 0.2 number of turn 450 circles, secondary with line footpath φ 0.08, the number of turn is 400 circles.R ₁=R ₂Be 330 Ω 1/8W, diode D is 2CP11, the small-sized electrochemical capacitor 10 μ f of C, bidirectional triode thyristor 1A/400V, R ₃Be 1K Ω, R ₄Be 20K, one-way SCR 3A/400V.Executive component air switch DZ10-25(is through repacking).

The utility model loss when normal electricity consumption is minimum, and this making model machine is when meeting load 6.5 KVA, and the device loss of measuring and calculating is 0.15VA.The device loss is 2.4 * 10 of a watt-hour meter capacity ^-5

This device is to the not influence of normal metering of watt-hour meter.

Claims (3)

1, one by two three-phase current-electric pressure converters that electromagnetic property is identical with electric parameter, and being connected into balanced bridge is the automatic outage anti-electricity-theft device of stealing reflection element.It is characterized in that two current-voltage converters A, a B, C triple coil are serially connected in the three-phase circuit respectively, one only is assembled in from watt-hour meter end points far away with automatic outage topworks, automatically cut off the power supply when stealing, another is right after the leading-out terminal at the three phase watt-hour meter power coil.The secondary coil of two three-phase current electric pressure converters is connected into electric bridge through resistance and lead.

2, anti-electricity-theft device as claimed in claim 1 is characterized in that three-phase current---electric pressure converter once adopts the unequal structure of the three-phase number of turn.

3, anti-electricity-theft device as claimed in claim 2 is characterized in that two converter secondaries are connected into two extension lines of balanced bridge, makes an insulated conductors wherein pass the seal screw hole of table lid and connector cover respectively and the electric lock mechanism that constitutes.

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