CN2814423Y

CN2814423Y - Electric cable insulation tester

Info

Publication number: CN2814423Y
Application number: CN 200520025146
Authority: CN
Inventors: 周国建; 黄维东; 禇敏; 刘凤元; 霍红光; 鞠卫国; 贾玉良; 张伟
Original assignee: Beijing Railway Bureau Zhangjiakou Paragraph; Beijing Railway Bureau Electric Engineering Department Of Tianjin Overhaul Services Section
Current assignee: Beijing Railway Bureau Zhangjiakou Paragraph; Beijing Railway Bureau Electric Engineering Department Of Tianjin Overhaul Services Section
Priority date: 2005-01-18
Filing date: 2005-01-18
Publication date: 2006-09-06
Anticipated expiration: 2015-01-18

Abstract

The utility model discloses an electric cable insulation tester which is mainly composed of a CPU circuit, a relay circuit, a relay drive circuit, a metering circuit, an input circuit and a high-voltage circuit, wherein an output end of the CPU circuit is connected with the drive circuit whose output end is connected with a surround extending 8155 chip, an output port of the 8155 chip is connected with an input port of the relay drive circuit, an output end of the relay drive circuit is connected with the input circuit whose output end is connected with an input end of an auto-ranging circuit, and the output end of the auto-ranging circuit is connected with an input end of the CPU circuit. The machine has the main function of making use of the high-speed characteristic of a single-chip microcomputer to circularly detect each core wire of the electric cable so as to find out core wires of the electric cable, which do not conform to specification, record the insulation resistance, and display electric cable numbering and insulation value after measuring; the machine can maximumly measure an electric cable with 48 cores. The machine can also measure a single core wire; a single measuring key is pressed after the selection of the core wire of the electric cable, which is to be measured, and the insulation resistance of the single core wire can be measured; in addition, the machine can also be used as a general rocking clock.

Description

The cable insulation proving installation

Technical field

The utility model relates to a kind of cable insulation proving installation, especially by cpu circuit, and relay circuit, relay drive circuit, metering circuit, the cable insulation proving installation that input circuit, high-tension circuit are formed.

Background technology

At present, the cable insulation test is more scabrous technical barrier always, because its distinctive difficulty, quick and precisely An Quan measurement mechanism never fundamentally solves, more hand table and the electronic megger of remaining used in market now, but this table people are very inconvenient in use, and measuring speed is slow, and measuring accuracy is not high.And when measuring the multiply cable, the frequent table line of changing, human factor is bigger, and measurement is wrong often to be occurred, and also very high to operating personnel's requirement simultaneously, inconvenient operation, human factor directly influence measurement result.

Technical scheme

The purpose of this utility model is exactly big in order to solve the unstable error of the measurement that often occurs in the cable insulation test, and measuring speed is slow, and dangerous shortcoming provides a kind of not only safety not only fast but also accurately, and easy to operate cable insulation proving installation.

In order to achieve the above object, the utility model has adopted by cpu circuit, relay circuit, and relay drive circuit, metering circuit, input circuit, high-tension circuit are formed, and the output of cpu circuit connects driving circuit; Output termination peripheral expansion 8155 chips of driving circuit; The output port of 8155 chips is succeeded the input port of electrical apparatus driving circuit; The output termination input circuit of relay drive circuit; The output termination auto range circuit input end of input circuit; The output termination cpu circuit of automatic range electricity circuit) input end.

Described driving circuit connects the expanded circuit of a plurality of chips 8155.

Described expanded circuit has 256 storage unit, can be used to store the data of test.

Described relay all adopts Japanese Omron relay.

Described metering circuit is formed the range change-over circuit by JA1, JA10, three relays of JA100; The measurement range of described resistance value is divided into 4 ranges, is 1M, 1M-10M, 10M-100M, 100M-1000M.

Owing to adopted technique scheme, set up AT89C51 single-chip microcomputer and peripheral expansion chip 8155 expansion interfaces, therefore can choose individual cable or Stranded cable circulation to measure in the cable number according to input, make and measure quick and precisely; Designed the stable of degree of accuracy that the relay circuit that contains 97 relays and metering circuit guaranteed measurement data and data simultaneously, again owing on cable core, added 500V voltage, short-circuit current is limited in 1mA, has not only satisfied needs of measuring but also the safety that can guarantee survey crew.

Below in conjunction with the drawings and specific embodiments the utility model is described in further detail;

Description of drawings

Fig. 1 is cable insulation proving installation card figure;

Fig. 2 is a cable insulation proving installation circuit FB(flow block).

1, cable number display screen, 2, insulation resistance display screen, 3, supply socket, 4, power switch, 5, ground hole, 6, digital keyboard, 7, measurement terminal, 8, input circuit, 9, auto range circuit, 10, metering circuit (A/D change-over circuit), 11, cpu circuit, 12 driving circuits, 13,8155 chips, 14, relay drive circuit, 15, high-voltage generator circuit, 16, power supply, 17,8279 integrated circuit, 18, keyboard, 19, the special IC of MAX7219 driven for emitting lights diode, 20, display circuit.

Embodiment

As shown in Figure 1: under the situation of outage, receive tested cable on the measurement terminal in order, crust ground connection, (the ground terminal on the panel, it be numbered 00) power-on switch 4, the numbering of pressing the tested cable of numerical key 6 input, numbering is made up of double figures, crust will be imported 00, No. 1 heart yearn input 01 etc.The double figures of input is the cable core numbering of beginning earlier, and the two digits of back input is for finishing the cable core numbering.Having imported the back starts working by the data of input by cable key machine.

At first select 00, the AJ0 relay energized, the BJ01 relay energized, crust and Line 1 are measured, and at this moment JA1, JA10, a JA1003 relay all are in full state, and computing machine judges that whether transformation result is greater than 1000M, as then carry out the test of next heart yearn greater than 1000M, as then judging whether greater than 100M,, preserve test result and cable core numbering as greater than 100M less than 1000M.Less than 100M, computing machine makes JA100 pick up, and carries out 10M～100M and measures, and preserve measurement result, finishes up to whole heart yearn measurements.

After measurement finished, cable number display screen 1 showed that the cable core numbering of insulation resistance minimum and insulating resistance value display screen 2 show insulating resistance value.At this moment push key up or down and can consult the insulating resistance value of other heart yearns.For the insulation resistance in a certain zone of centralized displaying, established＜1000M,＜100M,＜10M,＜4 keys of 1M, push one of them key after, can observe this regional insulation resistance situation by key up or down again.At every turn all to push 0 key clearly in the past carrying out new measurement.For the data that make measurement obtain confirming, established single survey key.Push single key of surveying after having imported cable number, at this moment instrument is only measured this a pair of cable core, makes the data of measurement obtain confirming.

As shown in Figure 2, full machine is a core with the AT89C51 single-chip microcomputer of cpu circuit 11, be aided with some peripheral circuits and constitute an integral body, at first in cpu circuit 11, after single-chip microcomputer executes initialize routine, begin corresponding work according to the instruction of keyboard input, the work of execution mainly contains 1, wireline test: according to the cable number of input, to the interval cable core cycle detection of choose, after finishing, test shows problematic cable core numbering and resistance value.2, test separately: the cable number according to input, the cable core of choosing is detected, after finishing, test shows cable core numbering and resistance value.3, common test: effect is equivalent to common megger.It is limited because of the driving force of the single-chip microcomputer of cpu circuit 11 output that the output of cpu circuit 11 connects driving circuit 12, after the load of wearing more, in order to guarantee the operate as normal of circuit, so add the load capacity of wearing that driving circuit 12 increases circuit.The drive wire that all carries out the loop test needs owing to 48 core cables is a lot, single-chip microcomputer does not have so much output port, need expand with 8155 chips 13, so output termination peripheral expansion 8155 chips 13 by driving circuit 12 come Extended Capabilities Port, and 8155 chips 13 have 255 bytes of memory devices, can also be used to storing the data of test simultaneously.The output port of 8155 chips 13 is succeeded the input port of electrical apparatus driving circuit 14, in test process, add the 500V DC voltage by high-pressure generating circuit 15 to it on the relay heart yearn, reliable for what guarantee to test, the selection of relay heart yearn is finished with relay, its effect is that the output signal of computing machine is amplified, and makes the reliable haustorium of relay.The output contact of relay drive circuit 14 connects input circuit 8, and input circuit 8 mainly is made up of relay tip, finishes the switching of cable core, and 48 core cables are carried out loop test; Output termination auto range circuit 9 input ends of input circuit 8, by auto range circuit 9 is that the hypothesis cable core is in shape when test begins, but test result was with bigger than normal when cable insulation was bad, and this is that computing machine will make range increase automatically, meets test request up to test result.Be input to test circuit (A/D change-over circuit) 10 then, because computing machine can only supplied with digital signal, so the test the result must by A D change-over circuit 10 be converted into digital signal, could import computing machine calculates and judges that the effect of A/D change-over circuit 10 is exactly that common electrical signal conversion is become digital signal.The output terminal of the single-chip microcomputer by cpu circuit 11 connects 8279 integrated circuit 17 of keyboard 18 special uses and the special IC 19 of keyboard 18 and MAX7219 driven for emitting lights diode, is input to display circuit 20 with the instruction that shows input and the result of test at the special IC 19 by MAX721 driven for emitting lights diode.

Claims

1, a kind of cable insulation proving installation, mainly by cpu circuit, relay circuit, relay drive circuit, metering circuit, input circuit, high-tension circuit are formed, and it is characterized in that: the output of cpu circuit (11) connects driving circuit (12); Output termination peripheral expansion 8155 chips (13) of driving circuit (12); The output port of 8155 chips (13) is succeeded the input port of electrical apparatus driving circuit (14); The output termination input circuit (8) of relay drive circuit (14); Output termination auto range circuit (9) input end of input circuit (8); The input end of the output termination cpu circuit (11) of auto range circuit (9).

2, according to the described cable insulation proving installation of claim 1, it is characterized in that: described driving circuit connects the expanded circuit of a plurality of chips 8155.

3, according to the described cable insulation proving installation of claim 1, it is characterized in that: described expanded circuit has 256 storage unit, can be used to store the data of test.

4, cable insulation proving installation according to claim 1 is characterized in that: described relay all adopts Japanese Omron relay.

5, require 1 described cable insulation proving installation, it is characterized in that: described metering circuit is formed the range change-over circuit by JA1, JA10, three relays of JA100; The measurement range of described resistance value is divided into 4 ranges, is 1M, 1M-10M, 10M-100M, 100M-1000M.