CN1045864A

CN1045864A - On-spot tester for leakage protector

Info

Publication number: CN1045864A
Application number: CN 89101676
Authority: CN
Inventors: 奚永源; 沈明生; 赵宝华
Original assignee: Shanghai Electric Appliance Research Inst Ministry Of Machine-Building And Ele
Current assignee: Shanghai Electric Appliance Research Inst Ministry Of Machine-Building And Ele
Priority date: 1989-03-21
Filing date: 1989-03-21
Publication date: 1990-10-03
Anticipated expiration: 2004-03-21
Also published as: CN1027837C

Abstract

A kind of on-spot tester for leakage protector; it is characterized in that comprising that constituting two of input circuit supports the survey pen; sampler with the leakage current sampling; the output AC signal transformation of sampler is become the converting means of the square-wave signal of same period with it; produce the timing device of accurate width-pulse and the comparison means that the pulse of the accurate width that sampling pulse and timing device produced that converting means produced is compared; in order to connect the relay road of simulation loop of electric leakage; and display device, described relay contact joining is in the Probing pen input circuit.

Description

On-spot tester for leakage protector

The present invention relates to the characteristic test device of leakage current action type protector.

Earth leakage protective device is the electrical equipment of protection electricity consumption personal safety, is applied to all electricity consumption departments.The characteristic of earth leakage protective device should meet country or international standard, could play due protective effect when running into mishap.The instrument of verifying various earth leakage protective device acting characteristics roughly has two classes.One class is used for the quality inspection of production run to product; The another kind of on-the-spot periodic check that is used for online earth leakage protective device, involved in the present invention is is the field-checking instrument of online earth leakage protective device under one situation of back.

The following weak point of on-spot tester ubiquity of present existing earth leakage protective device: at first; the verification principle adopts to the simulation leakage current that is passed to the certain hour certain numerical value by the school earth leakage protective device; then observe whether disjunction of earth leakage protective device, differentiate its performance with this.Owing to exist timing circuit and relay in this kind device, so checking precision is not high.In addition, the verification project of this checker is less, mostly only adopts a verification project, operation inconvenience in addition, and dangerous big, work efficiency is low.

Therefore, the object of the present invention is to provide a kind of measuring accuracy high, produce the field-checking instrument of adjusting the earth leakage protective device easy, that work efficiency is high.

On-spot tester for leakage protector of the present invention comprises Probing pen; in order to connect the relay of simulation loop of electric leakage; sampler with the leakage current sampling; the converting means that conversion is carried out in output to sampler; produce the timing device of accurate width-pulse and the comparison means that the accurate width-pulse that sampling pulse width and timing device produced that converting means produced is compared; qualified, underproof display device and hummer.

The invention has the advantages that the checking precision height, easy to use, the work efficiency height, security is good.And be not subjected to the influence of AC signal amplitude size, good output waveform.

Below in conjunction with accompanying drawing, a most preferred embodiment of the present invention is elaborated.

Fig. 1 is the formation block diagram of electric leakage on-spot tester of the present invention;

Fig. 2 is a more detailed pie graph embodiment illustrated in fig. 1;

Fig. 3 is the structure cut-open view of Probing pen of the present invention.

Referring to accompanying drawing 1, A represents red probe pen among the figure, connects the phase line of earth leakage protective device leading-out terminal during verification, and B is the black probe pen, the center line of ground wire or protector end of incoming cables during verification; J is an a pair of normally opened contact of connecting the relay 6 of simulation loop of electric leakage.The resistor network of the given different simulation leakage currents of 1 expression, the 2nd, with the sampler of analog current sampling, the output of sampler 2 becomes two rect.p. e2 through converting means 3, its width equals to simulate the duration of leakage current, the rising edge of e2 can drive the timing circuit 4 of a precision, its output e3 also is a rect.p., width is 40ms, 100ms, 200ms or 350ms, can select according to the needs of different check project by waver, the outputting standard pulse width signal e of the output e2 of converting means 3 and timing device 4 carries out width relatively in comparer 5, just the precedence on edge is more thereafter got back to low level as long as there is one among e2 or the e3, comparer 5 will produce a signal e4 and make relay 6 disjunctions, thereby cuts off the simulation loop of electric leakage.Like this, the maximum duration that the simulation loop of electric leakage is connected can not surpass 0.5 second, thereby resistor network 1 can be selected the resistance of smaller power for use, to reduce the volume and the cost of checker.

The verification project has four:

(1) under 1/2 I, whether is failure to actuate

(2) under I, whether select according to the technical target of the product regulation at 100ms or 200ms() in move.

(3) under 2 I, whether in 100ms, move.

(4) under 5 I, whether in 40ms, move.

If (1) of verification, the shelves at 350ms are put in the timing in the timing device 4, if earth leakage protective device is determined not disjunction in 350ms, then the e3 lower edge arrives first, and performance is qualified, and comparer 5 sends signal e5 and makes qualified display 7 work, and corresponding pilot lamp is bright; If within 350ms, move, represent that then the e2 negative edge arrives first, performance inconsistency lattice, comparer 5 send signal e6 and make defective display 8 work, and corresponding pilot lamp is bright, and hummer 9 is piped.

If (4) of verification, the 40ms shelves are put in the timing in the timing device 4, if earth leakage protective device at 40ms with interior disjunction, represent that then the negative edge of e2 arrives first, comparer 5 sends the e5 signal, and qualified display 7 is worked, qualified pilot lamp is bright; If not disjunction in 40ms represents that then the lower edge of e3 arrives first, comparer 5 sends signal e6 and makes defective display 8 work and hummer 9 is piped.

Like this, can carry out every verification.

Referring to accompanying drawing 2; the label identical with Fig. 1 represents that components identical or part, input Probing pen A connect by nuclear earth leakage protective device phase line leading-out terminal among Fig. 2; the end of incoming cables of Probing pen 2 ground wires or center line, 220 volts of power supplys are received through the normally opened contact of relay J simulation leakage current network are provided.Number in the figure 11 expression resistor networks are in order to provide different simulation leakage currents.Leakage current signal is by resistance R 1 and R2 and bridge rectifier taking-up, and it is transformed into square wave by comparer 12.DC voltage E is a threshold voltage, in order to improve antijamming capability.Square wave output is through D1; R1, C1 one-way latency network and logic level signal of comparer 3 outputs, its duration equals the duration of leakage current, first rising edge of the square wave of comparer 12 outputs drives trigger 14 upsets, it drives two

timing circuits

15 and 17, the square wave of a 5ms of timer 15 output and the signal of circuit 13 outputs or door 16 in superposition, the erroneous judgement that causes is broken because relay closes is bounced to prevent.Timing circuit 17 produces 4 kinds of timing value: 40ms by capacitor C 2 and resistor network 18; 100ma; 200ma and 350-500ms; select by the waver on the panel; to finish different verification projects; wherein 350-500ms is one grade of timing value of not adjusting, is used for the verification 1/2 I project of being failure to actuate, and promptly thinks promptly that when being failure to actuate in 350ms by the school earth leakage protective device it has moved never again.Trigger 19 is used for pilot relay J.When power switch closes, make trigger 19 set up high level state by biasing networks 28, make the relay J adhesive by driving circuit 20, begin verification thereby connect the simulation loop of electric leakage.The negative edge of timing circuit 17 outputs makes trigger 19 upsets, and relay J disconnects, and the simulation loop of electric leakage cuts off, and with protective resistance network 11, makes the leak resistance network can select the resistance of smaller power for use.

Or door 16 and the output signal of timing circuit 17 send into switching network 21 and make up according to different verification project demands, and trigger 22 and 23 are delivered in its output; If this verification project is qualified, then trigger 22 upsets make green formula pilot lamp D bright by driver 24; If this verification is underproof, then trigger 23 upsets make red led D bright through driver 25, and hummer 26 shouts a shout simultaneously.Yellow formula pilot lamp D represents having or not of leakage current.

Delay network 17 is for

trigger

4,9,12,13 provides initial bias, to guarantee setting up the predetermined original state that requires behind the power connection in 5 seconds.Delay network 16 is in order to stop trigger 14,19 and

timer

15 and 17 to accept trigger pip in the 6ms behind power connection.

Comparer 27 is used to check cell voltage.Input signal C and D are reference signal and battery voltage signal.If cell voltage is during less than certain setting, comparer 27 output high level, red led D is bright, tells operator's cell voltage less than setting, uses after should changing battery.

The power connection switch of checker is installed in the Probing pen.

The structure of probe pen A is identical with common Probing pen, handling safety.The structure of Probing pen B as shown in Figure 3.Wherein 31 is conducting probes, the 32nd, and bakelite cover (protheca), its front end has antislip ring; subordinate slips and touches conductive pin and get an electric shock when preventing verification, and the 33rd, phosphor bronze compression spring, the 34th, cover in the bakelite; the 35th, pocket buttons switch, the 36th, bakelite overcoat (back cover), the 37th, plastic protective sleeve; the 38th, trip bolt; the 39th, triple cable, the 40th, lead, an end are welded on the compression spring 33; the 41st, two leads of pushbutton switch 35, the 42nd, tight loop.

The each several part of on-spot tester for leakage protector of the present invention is positioned among the box body.

Claims

1, a kind of on-spot tester for leakage protector; it is characterized in that comprising that constituting two of input circuit supports the survey pen; sampler with the leakage current sampling; the output AC signal transformation of sampler is become the converting means of the square-wave signal of same period with it; produce the timing device of accurate width-pulse and the comparison means that the pulse of the accurate width that sampling pulse and timing device produced that converting means produced is compared; in order to connect the relay of simulation loop of electric leakage; and display device, described relay contact joining is in the Probing pen input circuit.

2, on-spot tester for leakage protector as claimed in claim 1 is characterized in that described converting means is made of comparer.