JPH0783298B2 - Track testing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] The present invention relates to a test device for various lines used as a communication line or a power supply line, etc., to prevent the occurrence of line faults and to promptly determine the cause when a fault occurs. For the purpose of providing a line testing device that can be easily found, the input means for inputting the wire type and wire length of the wire used in the wire, and the Data storage means for storing standard data of electric characteristic values per unit length, and calculating means for calculating electric characteristic values of the line based on the wire type and the wire length of the electric wire input by the input means. A measuring means for measuring an electric characteristic value of the line, a comparing means for comparing the electric characteristic value obtained by the calculating means with the electric characteristic value measured by the measuring means, and a ratio of the comparing means. Composed of a display means for performing display based on the results.

[Industrial application field]

The present invention relates to a test device for various lines used as a communication line or a power supply line.

In recent years, a data communication system in which a computer and a large number of terminal devices are connected by a communication line has been remarkably spread.

In general, paired cables and coaxial cables are often used as lines for communication lines, etc., but if a failure occurs in these lines, the computer or terminal device connected to the line malfunctions. There is a possibility that this will occur, and in conjunction with the progress of line multiplexing, the social impact of this is extremely large.

Therefore, it is extremely important to prevent a fault on the track and, in the unlikely event of a fault, quickly remove the fault.

[Conventional technology]

A computer or a terminal device connected to a data communication system may have a failure due to a failure or failure of the equipment itself, or a failure due to a failure of a line.

Causes of line-based failures include line breaks, poor contact,
Other than due to a defect in the cable used for the line such as deterioration of insulation resistance, due to forgetting to remove the used branch line or equipment connected to the line, or due to inadvertently connecting them in an abnormal state There is.

Conventionally, in order to prevent such obstacles due to the track, the line is tested and inspected by a test machine after completion of new construction or additional construction of the track.

However, in general, an obstacle based on a railroad is not one in which the railroad track is collected as one housing like a terminal device, but is laid over a long distance along a building or the like. In addition, since it is greatly affected by the environmental conditions around the track, it is often generated intermittently.

Therefore, even if the test after the completion of construction is normal, when the data communication system is actually operated, a failure may suddenly occur.

When such an intermittent failure occurs, in order to discover the cause and return it to a normal state, a test is performed using all testers such as a circuit tester, an insulation resistance meter, an oscilloscope, and a signal generator.

[Problems to be Solved by the Invention]

However, in general, the routes where wires are laid are complicated, and after a long period of time, unexpected lines and equipment are branched and connected, and power cables and other lines, wiring, piping, etc. are laid around them. Therefore, identify whether the cause of the intermittent failure is in the device such as the computer or terminal device, or in the track, or in another electrical equipment installed around them. It is not easy to do, and it is extremely difficult to find the cause of the intermittent disorder.

Therefore, if an intermittent failure occurs, a large number of engineers and construction personnel will need a lot of time and effort to find out the cause and restore it, and the direct and indirect economic loss will be extremely high. There was a big one.

The present invention has been made in view of the above problems, and an object thereof is to provide a line test apparatus capable of preventing the occurrence of a failure in a line and finding the cause of the failure early and easily. There is.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the line testing apparatus according to the invention of claim 1 is for inputting a wire type WT and a wire length WL of an electric wire 4 used in a line, as shown in FIG. Input means 23 and data storage means for storing standard data of electric characteristic values per unit length for various types of electric wires 4
21, a calculating means 20a for calculating the electric characteristic value of the line based on the wire type WT and the wire length WL of the electric wire input by the input means 23, and a measurement for measuring the electric characteristic value of the line. Means 13 to 16, a comparing means 20b for comparing the electrical characteristic value obtained by the calculating means 20a with the electrical characteristic value measured by the measuring means 13 to 16, and the comparing means 2
It is composed of a display means 22 for displaying based on the comparison result of 0b.

In addition to the above configuration, the line testing apparatus according to the invention of claim 2 has an estimating means 20c for estimating the cause of failure based on the comparison result of the comparing means 20b, and the display means 22 comprises:
It is configured to display the estimation result of the estimation means 20c.

[Work]

The input means 23 inputs the line type WT and the line length WL of the electric wire 4 used for the line to be tested.

The data storage means stores standard data of electric characteristic values per unit length for various types of electric wires 4.

The calculation means 20a calculates the electric characteristic value of the line based on the wire type WT and the wire length WL of the electric wire input by the input means 23.

The measuring means 13 to 16 actually measure the electric characteristic values of the line.

The comparing means 20b compares the electric characteristic value obtained by the calculating means 20a with the electric characteristic value measured by the measuring means 13-16.

The estimating means 20c estimates the cause of failure based on the comparison result of the comparing means 20b.

The display unit 22 displays based on the comparison result of the comparison unit 20b or the estimation result of the estimation unit 20c.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a test apparatus 1 showing an embodiment according to the present invention.

The test apparatus 1 is composed of a slave unit 2 and a master unit 3 that are independently portable, and one end side T or the other end side of an eight-core cable 4 including electric wires L1 to 8 and an earth wire E, respectively. It is connected to R.

The main unit 3 includes a line switching unit 11, a synchronization control unit 12, a resistance measuring unit 13, a capacitance measuring unit 14, an insulation resistance measuring unit 15, and an unbalance measuring unit.
16, input switching unit 17, rectification unit 18, AD conversion unit 19, control unit 2
0, memory 21, display unit 22, key input unit 23, communication device 24,
A busy indicator light 25, an alarm buzzer 26, etc. are provided.

The line switching unit 11 is composed of a connector or a terminal block for connecting the cable 4, a relay contact, a resistor, and the like, and among the electric wires L1 to 8 of the cable 4 in response to a switching signal from the control unit 20 described later. One or a pair of electric wires is selectively switched and connected to the synchronization control unit 12 or various measuring units 13 to 16 or the like.

Hereinafter, the electric wire or the electric wire pair selectively connected by the line switching unit 11 may be referred to as a “selected electric wire”.

The synchronization control unit 12 selects the electric wires L1 to 8 and the selected electric wire L1.
Signals for synchronizing with the slave unit 2 to be described later are transmitted or received with respect to the connection points of 8 and the like.

The resistance measuring unit 13 measures the DC resistance of the selected electric wire and outputs the resistance value Rm which is the measured value.

The capacitance measuring unit 14 measures the capacitance of the selected electric wire and outputs the capacitance Cm.

The resistance value Rm and the capacitance Cm are measured at a low voltage of about a few plus volts or less.

The insulation resistance measuring unit 15 measures the insulation resistance of the selected wire,
Outputs insulation resistance value Mm. The insulation resistance value Mm is measured at a high voltage of about several hundred volts.

The unbalance measuring unit 16 performs a pseudo induction test with the test signal from the slave unit 2 and measures the unbalance degree Um, which is the degree of unbalance of the selected wire. The unbalance measuring unit 16 includes a differential amplifier that differentially amplifies an input signal based on the in-phase test signal applied to the selected electric wire (electric wire pair) by the slave unit 2.

The input switching unit 17 selectively switches and outputs the outputs from the various measuring units 13 to 16.

The rectifying unit 18 rectifies the output from the input switching unit 17, and smoothes and shapes the waveform as necessary.

The AD conversion unit 19 quantizes the output from the rectification unit 18 and converts it into measurement data Dm that is a digital value.

The control unit 20 controls the line type WT and the line length input from the key input unit 23.
An arithmetic unit 20a for calculating comparison data Dc which is an electrical characteristic value of the cable 4 based on the standard data Ds stored in the WL and the memory 21, a comparison unit 20b for comparing the comparison data Dc with an actual measurement value, and a comparison unit 20b. The estimation unit 20c and the like for estimating the cause of failure based on the comparison result of 1.

The control unit 20 is composed of a microprocessor, an IO element, other peripheral elements, and the like, and in addition to the above-described operation, reads the measurement data Dm from the AD conversion unit 19, reads and writes data from and into the memory 21, and displays the data. The master unit 3 is controlled as a whole, such as displaying on 22 and inputting from the key input unit 23 and outputting to the alarm buzzer 26, and outputting a switching signal for the line switching unit 11 by a timer based on a clock signal. To do.

The memory 21 is composed of ROM, RAM, etc., stores programs necessary for control by the control unit 20, standard data Ds, etc., and stores various data read or generated by the control unit 20. Store.

FIG. 2 is a diagram showing a part of the standard data Ds stored in the memory 21.

The standard data Ds is the resistance value per unit line length [Ω / m] and the capacitance [pF / m], the unbalance degree [%] for each of the wire types WT indicated by the model for various cables. , The insulation resistance value [MΩ] and the like, and when the line type WT is designated, the data of the electric characteristic value corresponding thereto is read out.

The display unit 22 is composed of a liquid crystal panel having an appropriate size, and displays the measurement data Dm measured by the measuring units 13 to 16, the calculation result or the inference result in the control unit 20, and other messages.

The key input unit 23 includes a numeric keypad, a control key, etc., for inputting the line type WT and the line length WL of the cable 4 to be tested as line data Dl, as well as other setting data and command data. Used for. By inputting the wire type WT, the number of core wires of the cable 4 is automatically determined by the control unit 20.

The key input unit 23 is also used to input an external event or the like necessary for inference in the process of executing inference by the estimation unit 20c.

The communication device 24 is for making a telephone call with the handset 2.

The busy indicator light 25 is turned on when the actual measurement test of the cable 4 is being performed. During this time, since the voltage for measurement is applied to the cable 4, it is impossible to make a call by the communication device 24.

The alarm busher 26 sounds when there is an abnormality in the track test.

Next, in the slave unit 2, the line switching unit 31, the synchronization control unit 32, the test signal generation unit 33, the control unit 34, the communication device 35, the busy indicator light.
36 etc. are provided.

The line switching unit 31 includes a connector or a terminal block for connecting the cable 4, a relay contact, a resistor, and the like similarly to the line switching unit 11 of the master unit 3, and the master unit receives a switching signal from the control unit 34. Wire L1 corresponding to the wire selected by 3
8 are selectively switched, an appropriate terminating resistor is connected to the selected electric wire, short-circuited, opened, and the test signal generator 33 and the like are connected.

The synchronization control unit 32 cooperates with the synchronization control unit 12 of the parent device 3 to transmit or receive a signal for establishing synchronization.

The test signal generator 33 is provided with an oscillator that outputs an oscillation signal composed of a sine wave of about 1 KHz, and this oscillation signal is output to the selected electric wire (electric wire pair) via resistors having the same resistance value. To be done. That is, the test signal generator 33 applies the test signals having the same phase and the same amplitude to each of the wire pairs of the wires L1 to L8.

The control unit 34 includes a so-called sequence controller or the like, and controls the entire slave unit 2 by outputting a switching signal for the line switching unit 31 by a timer based on a clock signal. The data necessary for controlling the number of cores of the cable 4, the presence / absence of measurement of insulation resistance, and the like are sent from the parent device 3 through the cable 4 before or during the test.

The communication device 35 is for making a telephone call with the base unit 3.

The busy indicator light 36, like the busy indicator light 25 of the master device 3, lights up when the actual measurement test of the cable 4 is being performed.

Next, the contents of the line test by the test apparatus 1 and the test apparatus 1
The processing operation will be described with reference to the flowcharts shown in FIGS.

FIG. 3 is a flowchart showing a schematic flow of the line test by the test apparatus 1.

First, the slave unit 2 and the master unit 3 are connected to the target cable 4 (step # 11).

The line data Dl of the cable 4 is input from the key input unit 23 (step # 12). The track data Dl is input based on construction drawings or specifications, but it is preferable that the track data Dl be input after checking the actual product. The line length WL may be the estimated length.

Based on the input line data Dl, the standard data Ds of the corresponding line type WT is read from the memory 21, and the calculation unit 20a calculates the comparison data Dc by multiplying the standard data Ds by the line length WL ( Step # 13).

Resistance value Rm, capacitance Cm, degree of imbalance by each measuring unit 13-16
Um and insulation resistance value Mm are measured (step # 14).

Whether all of the measurement data Dm based on these measurement values are within the normal range is determined by the comparison unit 20b.
Determined by comparing with c (step # 1
Five).

If it is within the normal range, a message indicating that the cable 4 is normal and the measurement data Dm are displayed on the display unit 22 and printed by a printer (not shown) as needed (step # 17).

If it is not within the normal range, a fault diagnosis is executed by the estimation unit 20c (step # 16), and the diagnosis result and measurement data Dm
Is also displayed.

FIG. 4 is a flowchart showing the processing contents of the measurement routine.

When a measurement start command is input from the key input unit 23 (Yes in step # 21), the capacitance measuring unit 14 measures the capacitance Cm, the resistance measuring unit 13 measures the resistance value Rm, and the unbalance measuring unit.
Measurement of unbalance Um by 16 is performed sequentially (Step #
22-24).

The insulation resistance measured by the insulation resistance measuring unit 15 is limited only when all of these measured values are within the normal range (Yes in step # 25) and there is an instruction to start insulation resistance measurement (yes in step # 26). The measurement is performed, and the insulation resistance value Mm is actually measured (step # 27).

FIG. 5 is a flowchart showing the operation contents in each actual measurement.

First, the line switching units 11 and 31 select electric wires (step # 31).

An actual measurement is performed by any of the measurement units 13 to 16, and the measured value is input (step # 32).

Measurement data Dm and comparison data based on the input measurement values
Dc is compared (step # 33).

It is determined whether the measurement data Dm is within the normal range (step # 34).

If it is within the normal range, the measurement data Dm is stored in a predetermined area of the memory 21 (step # 36), and then, until the measurement of all electric wires is completed (step # 37), the process returns to step # 31, The line switching units 11 and 31 are switched to select the next electric wire and the actual measurement is performed.

If it is not within the normal range, the alarm buzzer 26 is sounded (step # 35) and the process proceeds to step # 36.

One process shown in the flowchart of FIG. 5, that is, 1
The processing of steps # 32 to # 36 for one selected electric wire is completed in about several seconds, and this is executed for each electric wire pair of the cable 4 and all combinations of each electric wire and the ground.

Further, in the fault diagnosis process of step # 16 of the flowchart shown in FIG. 3, the input line data Dl, external event, all measured data Dm, and comparison data Dc are input.
Based on the result of comparison with etc., other cables are branched and connected to the cable 4, the device is still connected to the cable 4 or its branched cable without being removed, and the cable 4 is defective in insulation. That the cable 4 is broken, that the connection of the cable 4 is poor and contact failure is occurring, and it is in a pseudo broken state.
The cause of various faults is inferred, such as a connection error in the child device 2, the parent device 3, or the cable 4.

According to the above-described embodiment, by performing the line test by the test apparatus 1, the comparison data Dc and the measurement data Dm are compared to display whether or not the cable 4 is normal, and
It is possible to easily know the measurement data Dm of the cable 4, the probable cause of the failure by inference, the place to be inspected, the order, etc., and even a person who does not have good experience can quickly and quickly find the cause of the failure with a small amount of labor and time. Can be easily found.

As a result, the reliability of the determination of the quality of the cable 4 can be improved, the occurrence of a failure caused by the cable 4 can be prevented, and an accident due to a failure such as a search for a failure location or a failure cause after the failure occurs. Countermeasures can be taken promptly, time and cost due to a failure of the cable 4 can be significantly reduced, and reliability of the data communication system using the cable 4 can be improved.

Moreover, according to the above-mentioned embodiment, a large number of electric wires of the cable 4 are provided.
Since L1 to 8 are automatically switched and measurements for various items are sequentially performed, the time required for the line test is significantly reduced.

According to the above-mentioned embodiment, since the pseudo induction test by the unbalance measuring unit 16 etc. is performed, the cable 4
Can be easily known, and whether the cable 4 is in a state susceptible to inductive interference, whether the branch line, equipment, etc. have been forgotten to be removed can be easily known.

According to the above-described embodiment, the capacitance Cm and the resistance value Rm are measured before the insulation resistance measurement, and the insulation resistance measurement unit 15 performs the insulation resistance measurement only when these measurement results are normal or good. Therefore, there is no risk of forgetting to remove the cable 4 and damaging the connected equipment, safety is ensured, and insulation resistance measurement can be carried out with confidence.

In the above-described embodiment, various items other than those described above, such as measurement of the crosstalk state of the cable 4 and measurement of line noise, may be added as measurement items in the line test.

In the above-described embodiment, the determination as to whether or not the range is the normal range in steps # 15, 25, and 34 may be different in the content of the determination, the allowable range, and the like. As items to be input from the key input unit 23, items relating to environmental conditions such as the surrounding conditions where the cable 4 is laid, weather, temperature, etc. may be input.

In the above-mentioned embodiment, omitting a part of the measuring units 13 to 16,
Further, another measuring unit may be added. A plasma display, a CRT, a printer, or the like can be used as the display unit 22, and an alarm buzzer 26 or an appropriate indicator light can also be used. In addition, the configurations of the slave unit 2, the master unit 3, and the respective units may be various other than those described above.

The test apparatus 1 as described above is used for various cables other than the cable 4, various cables laid outside the building such as overhead or underground, and also for communication such as telephone, telegraph, railway signal, clock, firefighting and cable vision. It can be applied to test various lines such as used cables, other communication lines, and power supply lines.

〔The invention's effect〕

According to the present invention, it becomes possible to prevent the occurrence of a fault in a line and to easily find the cause of the fault when it occurs.

[Brief description of drawings]

FIG. 1 is a block diagram of a test apparatus showing an embodiment according to the present invention, FIG. 2 is a view showing a part of standard data stored in a memory, and FIG. 3 is a schematic flow of a line test by the test apparatus. FIG. 4 is a flowchart showing the processing contents of the measurement routine, and FIG. 5 is a flowchart showing the operation contents in each actual measurement. In the figure, 1 is a test device, 4 is a cable (electric wire), 13 is a resistance measuring section (measuring means), 14 is a capacitance measuring section (measuring means), 15 is an insulation resistance measuring section (measuring means), and 16 is unbalanced. Measuring unit (measuring means), 20a calculating unit (calculating unit), 20b comparing unit (comparing unit), 20c estimating unit (estimating unit), 21 memory (data storing unit), 22 display unit (displaying unit) ), 23 is a key input part (input means), WT is a line type, and WL is a line length.

Claims (2)

[Claims] 1. An input means (23) for inputting a wire type (WT) and a wire length (WL) of an electric wire (4) used for a line.
And a data storage means (2) storing standard data of electric characteristic values per unit length for various types of electric wires (4).
1) and the wire type (WT) of the electric wire input by the input means (23)
And a calculating means (20a) for calculating the electric characteristic value of the line based on the line length (WL), and a measuring means (13) for measuring the electric characteristic value of the line.
(16), a comparing means (20b) for comparing the electric characteristic value obtained by the calculating means (20a) with the electric characteristic value measured by the measuring means (13) to (16), and the comparing means. A line testing device comprising: a display means (22) for displaying based on the comparison result of (20b). 2. An estimation means (20c) for estimating a cause of failure based on a comparison result of the comparison means (20b), wherein the display means (22) displays the estimation result of the estimation means (20c). The line testing device according to claim 1, characterized in that.