CN1044167A

CN1044167A - Electrical equipment ground detection device and method

Info

Publication number: CN1044167A
Application number: CN 89100006
Authority: CN
Inventors: 孙景林
Original assignee: JINZHOU SCIENCE AND TECHONOLOGY INST RAILWAYS BUREAU OF SHENYANG
Current assignee: JINZHOU SCIENCE AND TECHONOLOGY INST RAILWAYS BUREAU OF SHENYANG
Priority date: 1989-01-10
Filing date: 1989-01-10
Publication date: 1990-07-25

Abstract

A kind of electrical equipment ground detection device that constitutes by positive and negative end ground connection arbiter, inverter and clamp on amperemeter, be used for the ground connection of various electrical equipments is detected, detection method must be judged the anode or the negativing ending grounding of load earlier with positive and negative end ground connection arbiter, the variation of electric current in electric current that provides with inverter and the clamp on amperemeter again, judge earth point, this apparatus structure is simple, and is easy to operate, be easy to grasp, and it is convenient very rapidly to search earth fault.

Description

Electrical equipment ground detection device and method

The present invention relates to a kind of electrical equipment ground detection device.

At present in the electrical equipment that uses, particularly at diesel locomotive, in the electric locomotive, for the negative terminal that makes electrical equipment effectively is connected reliably with the negative terminal of power-supply device, and adopted two-wire to return the circuit connecting of negative system, as Fig. 1, if the negative terminal bar line ground connection in the equipment, because two-wire returns the characteristics of negative system circuit, making the negative power end of all devices all connect with the earth, is which point ground connection of which the bar line in which bunch in order to detect, and whole lead one rules need be taken off, measure on rule ground over the ground with ohmmeter, up to finding out earth fault, therefore, it is extremely difficult adopting this method to look for earth point.

Purpose of the present invention just provides a kind of electrical equipment ground detection device, and this device has utilized the principle of inverter, changes direct supply into AC power and by clamp on amperemeter earth fault is detected.

Characteristics of the present invention are: it is to be used for direct supply is become power frequency AC by the inverter that triode, resistance and appendiron core transformer constitute; The positive and negative terminal earthing discrimination device that pilot lamp constitutes is the anode or the negativing ending grounding of load in order to judgement; Clamp on amperemeter has electric current in order to detect in which bunch in the circuit; One end ground connection of inverter output end, the other end is the test side, and connects with the plus end of power supply, is stuck on each wire harness detecting electric current with clamp on amperemeter, and comes the position of the localization of faults according to current variation.

Below in conjunction with accompanying drawing the present invention is described in detail as follows:

Fig. 1 is negative system circuit connection synoptic diagram for two-wire returns;

Fig. 2 (A), Fig. 2 (B) are electrical equipment ground detection device circuit theory diagrams;

Fig. 3 is an electrical equipment ground detection device outside drawing.

The coupling method of circuit shown in Figure 1 is that two-wire returns negative system circuit coupling method.11 is the anode of 110V direct supply among Fig. 1,12 is its negative terminal, 1,2,3 are load, 4,5,6,7,8 is the contact of relay, 9 anode hypothesis earth points for

load

3,10 negative terminal hypothesis earth points for load 3, if anode 9 ground connection of load 3, it only influences the work of load 3, therefore is examined out than being easier to, still, if negative terminal 10 ground connection of load 3, because two-wire returns negative system circuit, the negative terminal of load 1,2,3 is all connected with the earth, be difficult for like this being detected.

Inverter shown in Fig. 2 (A) and Fig. 2 (B) and positive and negative end ground connection arbiter have constituted the electrical equipment ground detection device jointly; Fig. 2 (A) is the inverter schematic diagram, and it is by triode, resistance, and appendiron core transformer, switch and pilot lamp constitute, and 13 is power positive end among Fig. 2 (A), and 14 is its negative terminal, and this power source voltage can adopt the direct supply of 6～22V; 49,50 is pliotron in 3DK or the 3DG type; 16 is protective tube; 15,17 is resistance, and its value scope is 45～60 Ω; 18,19 is resistance, and its value scope is 2～4K Ω, and 20,21 is the coil around limit, appendiron core transformer source, and the number of turn can be selected between 35～60 circles; 22,23 also is coil around limit, appendiron core transformer source, and the number of turn can be selected between 20～40 circles; 24,25 is that the number of turn of its coil can be selected in respectively between 5～10 circles, 25～35 circles around the coil on appendiron core transformer time limit; 26 are the setup test pilot lamp; 27 is the inverter relay indicating light; 28,29 is two contacts of switch 30; 31 is test lead; Fig. 2 (B) is the positive and negative end ground connection of a load arbiter schematic diagram.32 is the negativing ending grounding pilot lamp among Fig. 2 (B); 33 is the positive ending grounding pilot lamp; 34 are comparison brightness standard pilot lamp; 35 is direct supply 110V anode, and 36 is its negative terminal.

Fig. 3 is an electrical equipment ground detection device outside drawing, and 37,38 are respectively 6～22 volts of positive and negative input terminals of direct supply among Fig. 3; 39, the 40 positive and negative input terminals that are respectively direct supply 110V; 41 is the negativing ending grounding pilot lamp; 42 is the positive ending grounding pilot lamp; 43 are comparison brightness standard pilot lamp; 44 is Test Switchboard, and wherein one grade is the setup test shelves, and another shelves are the test shelves; 45 are the setup test pilot lamp; 46 is the inverter relay indicating light; 47 is the test lead leading-out terminal; 48 is ground terminal; 51 is shell.

The most preferred embodiment of the inverter that the present invention adopts is shown in Fig. 2 (A), and wherein each component parameter is selected as follows: resistance 15,17 is 51 Ω; Resistance 18,19 is 3K Ω; Connect the 22V direct supply between the positive and negative terminal 13,14 of power supply; Triode 49,50 is 3DK ₄Type; Coil 20,21 is 48 circles;

Coil

22,23 is 30 circles; Coil 24 is 9 circles; Coil 25 is 32 circles; Pilot lamp 26 is the 5V pilot lamp; Pilot lamp 27 is the 10V pilot lamp.

When two-wire as shown in Figure 1 returns the anode of load in the negative system circuit or negativing ending grounding, must be anode or negativing ending grounding at first just, can be judged according to the situation that pilot lamp is lighted with positive and negative end ground connection arbiter differentiation.If anode 9 ground connection of load 3, and relay 7,8 contact is in on-state, pilot lamp 33 among Fig. 2 (B), 34 light, and the two brightness is identical, then the indication equipment positive ending grounding, but, if the contact of relay 7,8 is in off-state, pilot lamp 32 is lighted, but its brightness and pilot lamp 34 brightness differ bigger, this also illustrates it is the situation that belongs to positive ending grounding, if negative terminal 10 ground connection of the load among Fig. 13, pilot lamp 32 among Fig. 2 (B), 34 light and brightness identical, then the expression be the negativing ending grounding of load 3.After judging anode or negativing ending grounding, can carry out troubleshooting of faults, if positive ending grounding, then can be according to the control position, find the trouble spot, if be negativing ending grounding, also must add clamp on amperemeter with inverter further diagnoses, the test lead 31 of the inverter shown in Fig. 2 (A) is linked with the power-terminal that two-wire returns negative system circuit, after inverter relay indicating light 27 and setup test pilot lamp 26 are lighted, the contact 29 of switch 30 is connected, and the negative terminal wire harness of each load is measured with pincerlike meter, at the appearance electric current of wire harness and the separation of current vanishes, be the earth point of wire harness, so just can accurately find the position of ground connection.

The present invention compared with prior art has following advantage: adopt this method, can save disconnect process, and can find rapidly earthing position, can improve speed more than 10 times, this apparatus structure is simple, and cost is low, and is not high to personnel's specification requirement in the operation, is easy to grasp.

Claims

1, a kind of electrical equipment ground detection device, it is characterized in that: it is the positive and negative end ground connection arbiter that is made of positive ending grounding pilot lamp, negativing ending grounding pilot lamp, standard pilot lamp, and inverter and clamp on amperemeter that triode, resistance, protective tube, pilot lamp, switch, appendiron core transformer constitute are formed;

2, according to the described electrical equipment ground detection device of claim 1, it is characterized in that: judge earlier the anode or the negativing ending grounding of load with positive and negative end ground connection arbiter, the variation that electric current is indicated in electric current that provides with inverter and the clamp on amperemeter comes the detection of ground faults point again.