JP2767296B2 - Cable connection tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field of the present invention> The present invention relates to a terminal treatment of a communication multi-pair cable in which a plurality of pairs of lines (hereinafter referred to as a pair line) are bundled and a connection between the cables. The present invention relates to a cable connection tester for testing whether or not the test is performed without error.

<Prior Art> For example, as shown in a cross section in FIG. 8, a cable for a telephone line is composed of a pair of lines L1a and L1b and a pair of lines L2a and L2b as one unit (one quad). Five bundles of these quads are bundled together for every 10CH, and a plurality of these bundles are bundled together to form a larger bundle, for example, a single cable for 1800CH or 3600CH in total.

Such a cable has a roll length of, for example, 200 m, and when the laying distance is longer than this length, it is necessary to add and lay the cable.

In recent years, a method of connecting cables by hand has been adopted, from a method of manually connecting cables one by one to a method of providing a connector for every 10 CH.

However, since the operation of connecting the cable to the connector and the operation of assembling the cable end portion including the connector are performed manually, it is easy to cause misplacement of the wires in the connector, poor connection, disconnection or short circuit due to the operation of the assembly.

For this reason, conventionally, it was tested using a cable connection tester 1 as shown in FIG. 9 whether the work of connecting the connectors and the work of putting together the end portions were performed correctly.

That is, the cable connection tester 1 has a DC power supply 2, a voltmeter 3, and the outputs of the DC power supply 2 connected to the connector 4.
Output switching means 5 for outputting to any of the three lines,
Input switching means 7 for connecting any of the 20 lines connected to the input connector 6 to the voltmeter 3
It is composed of

Here, 2 of 10CH units connected to one end of the cable 10
Connector 11a, 11b to output connector 4, respectively
Connected to the input connector 6, the connection connectors 11a, 11b
A predetermined connection cord 13 is used to connect between the connection connectors 12a and 12b on the other end corresponding to.

After the connection is made in this manner, the input switching means 7 is switched on while DC power is being input to one of the 20 lines.
When the operation is correctly performed, a DC voltage is generated only on the line corresponding to the line to which the DC power has been input.

Therefore, if a voltage is generated in a line other than that line, a short circuit occurs.If no voltage is generated in all lines, a disconnection occurs.If a voltage is not generated in a desired line and a voltage is generated in another line, it is confirmed that the lines are interchanged. it can.

If this test is performed for all 20 lines, the lines for 10CH with the connectors 11a and 12a at both ends and the connectors
The quality of the operation for the 10 CH lines having both ends of 11b and 12b can be understood.

Thereafter, tests for other 10 CHs are sequentially performed in the same manner, and the defective line is repaired by reconnecting the connector.

<Problem to be solved> However, in the test described above, the replacement work of the connector and the operation of the tester are performed at one end of the cable.
On the other end side, a corresponding connector must be selected and the connection cord 13 must be replaced, and a plurality of workers are at both ends of the cable 10 and perform test work while communicating with each other. This is a very complicated and time-consuming task.

The present invention has been made to solve this problem,
It is an object of the present invention to provide a cable connection tester capable of performing a connection test with only one end of a cable.

<Means for Solving the Problems> In order to solve the problems, a cable connection tester of the present invention supplies a DC signal of a predetermined level to a desired line of a cable, and detects the level of this line or another line. Level detection means, crosstalk determination means for determining crosstalk between lines based on a detection level from the level detection means, capacity detection means for detecting line capacitance of lines forming a pair of cables, and Disconnection determining means for determining disconnection of the paired line; and applying a predetermined AC signal to the cable paired line,
Crosstalk detecting means for detecting the crosstalk of this signal in another paired line, and interchanging means for judging whether two pairs of lines are interchanged based on the crosstalk are provided.

<Operation> Therefore, it is possible to perform the mixed line determination, the disconnection determination, and the misplacement determination of each line at one end of the cable.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a cable connection tester 20 according to one embodiment.

Reference numeral 21 denotes a connector for 100 cables, and reference numeral 22 denotes a first switching circuit for switching all 200 lines from the connector 21 to a second switching circuit 23 or a third switching circuit 25 described later.

23 is a signal from the first switching circuit 22 as shown in FIG.
Switches Sa (1) to Sa (200) for applying an H-level or L-level voltage to 0 lines, respectively, and a switch Sb for selectively outputting any one of the 200 lines
This is a second switching circuit composed of (1) to Sb (200), and the switching is performed by a switching signal from a switching control means 32 described later.

Reference numeral 24 denotes a level detection circuit for detecting the voltage level of the line selected by the second switching circuit 23.

Reference numeral 25 denotes a third switching circuit, as shown in FIG.
From the 100CH (200 lines) line from the first switching circuit 22
Switches Sc (1) to Sc for selecting and outputting 2CH (4 lines) each
(200), switches Sd (1) to Sd (4) for switching the selected 2CH line to the capacitance detection circuit 26 or the crosstalk detection circuit 27 described later, and 2CH for the 2CH switched to the capacitance detection circuit 26 Switches Se (1) and Se that select 1CH
(2). The switching of each switch is performed by the switching control means 32 as described above (however, a control line for the switch Sc is not shown).

The capacitance detection circuit 26 is the one selected by the third switching circuit 25.
An oscillation circuit 26a that oscillates with a time constant of this line capacitance and a predetermined resistance so as to detect the line capacitance of the paired lines, and a counting circuit 26b that counts a predetermined reference signal using this oscillation output as a gate signal. Thus, a count value corresponding to the line capacitance is output.

The crosstalk detection circuit 27 applies an AC signal of a predetermined frequency from a signal source 27a to one pair of lines with respect to two pairs (one quad) of lines selected by the third switching circuit 25, An AC voltmeter 27b is connected to the other pair of lines.

28 is a determination unit that receives signals from the level detection circuit 24, the capacitance detection circuit 26, and the crosstalk detection circuit 27, compares the signals with determination criteria for each, and outputs a determination result, 29 is a storage unit that stores the determination result, Reference numeral 30 denotes display means for displaying the stored contents on the display 31.

The switching control means 32 performs switching of each of the first, second, and third switching circuits 22, 23, and 25 and switching of the criterion of the determination means 28 in a predetermined order according to a command signal from the operation unit 33. .

Next, the operation of the cable connection tester 20 will be described.

As shown in FIG. 4, a cable connection test is performed on one of the connectors 41 (1) to 41 (36) attached in units of 100CH to the other end with the one end of the cable 40 of 3600CH opened. When the connector 21 of the device 20 is connected and the operation unit 33 instructs the crosstalk test, the processing procedure is as shown in the flowchart of FIG.

That is, the line for 100 CH is switched to the second switching circuit 23 side by the first switching circuit 22, the variable n is initialized to 1, and
The switch Sa (n) is set to the “H” side, the switches other than the switch Sa (n) are set to “L”, the switch Sb (n) is closed, and the level detection circuit 24 determines whether the level is the “L” level or not. means
It is determined by step 28 (steps 1 to 5).

When the level of this line is at the "H" level, it is assumed that there is no mixing of this line and other lines, and the value of n is incremented by 1 until n becomes "200", and the process is repeated (step 6, 7).

If it is determined in step 5 that the line is at the "L" level, it is assumed that the line is mixed with other untested lines, the switch Sa (n) is on the "L" side, and the switches other than the switch Sa (n) are "H". Side, a variable m larger than n is set, the switch Sb (m) is closed, and the level is changed to a level detection circuit.
24 is determined by the determination means 28. (Steps 8-1
1).

If the level is determined to be "L" level, the level detection circuit 24 and the determination means 28 determine that the m-th line is mixed with the n-th line, and this value (n, m) is stored. (Step 12).

Thereafter, the same test up to "200" is performed while increasing the value of m by one (steps 13 and 14).

When m becomes "200", the process returns to step 6, the level test is performed for all the lines, the crosstalk line is stored, and the crosstalk test ends.

 Next, when a disconnection test is instructed, the processing shown in FIG. 6 is performed.

That is, the line for 100 CH is switched to the third switching circuit 25 by the first switching circuit 22, and the switches Sd (1) to Sd
(4) is connected to the switches Se (1) and Se (2) (steps 1 and 2).

Next, variables n and m are initialized to n = 1 and m = 2, and switches Sc (2n-1) and Sc (2n) and switches Sc (2m-
1), Sc (2m) is closed and switches Se (1), Se
(2) is switched to the CH (n) side, and the line capacitance is detected by the capacitance detection circuit 26 (steps 3 to 5).

Here, the determination of the detection capacity of the CH (n) line is performed by the determination means.
28 (step 6).

This determination is for determining whether or not the measured capacity is within a predetermined capacity range that is set in advance based on the inter-line capacity per length of a pair of lines and the cable laying length.

If the measured capacity does not fall within the predetermined range, the channel name "n" is stored in the storage means 29 assuming that this line has a disconnection fault (step 7).

Next, the switches Se (1) and Se (2) are switched to the CH (m) side, and the capacity detection and the determination are performed in the same manner as described above.
Does not reach "100", n and m are incremented by 2 and the process returns to step 4 (steps 8 to 12).

As described above, the disconnection test is performed on all the 100CH lines.

Next, when an exchange test is instructed, the processing of the procedure shown in FIG. 7 is performed.

That is, the line for 100 CH is switched to the third switching circuit 25 side by the first switching circuit 22, and the switches Sd (1), Sd
(2) is switched to the crosstalk detection circuit 27 side, and n,
m is initialized to n = 1 and m = 2, respectively (steps 1 to 3).

Next, the switch Sc (2n
-1), Sc (2n), Sc (2m-1), Sc (2m) are closed, crosstalk is detected, and the magnitude of the value is determined based on the reference value (steps 4, 5).

This determination is performed in advance using a crosstalk value (for example, 80 db) with two pairs of one quad as a reference value, and utilizing that the crosstalk value is extremely deteriorated when there is a line misplacement within one quad. I have.

If the crosstalk is other than the reference value, the channel value (n, m) is stored. If m does not reach 100, n and m are each increased by 2 and the process returns to step 4 (steps 6 to 8). .

In this way, it is possible to test for faults due to line misplacement.

Since the above three test results are displayed on the display 31 by the display means 30, the operator can easily know the faulty line.

When the test for 100 channels is completed as described above, the same test as described above is performed on the other connectors 41 (2) to 41 (2) of the cable 40.
Repeat for 41 (36).

As a result, crosstalk, disconnection, and misplacement faults due to the work of line end processing for all 3600CHs are detected.

The processing for the failure may be performed every time the 100CH test is performed, or may be performed after all the tests are completed.

<Another embodiment of the present invention> In the above embodiment, a capacitance detection circuit for a disconnection test is used.
Although the oscillation circuit 26 includes the oscillation circuit 26a and the counting circuit 26b, other known capacitance detection directions (for example, bridge detection) may be used.

In the above-described embodiment, the test is continuously performed in units of 100 CHs. However, the test may be performed in units of 10 CHs or 200 CHs, and can be changed according to the end treatment of the cable.

<Effect of the present invention> The cable connection tester of the present invention, as described above,
A DC level is applied to a desired line of a cable, and a level of the line or another line is detected, thereby detecting a crosstalk (short circuit) fault between the lines, and a disconnection by detecting a line capacitance of a paired line. Since a fault is detected and a crosstalk between two pairs of lines is detected to detect a crossover fault, each fault of the laid cable is changed while one end of the cable is left open. The test can be performed, and the test operation is greatly simplified and can be performed in a short time as compared with the conventional method of performing the test while communicating at both ends of the cable.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment, FIGS. 2 and 3 are circuit diagrams showing a part of the embodiment, and FIG. 4 is a diagram for explaining connection between a cable and a tester. Figures, 5 and 6
FIG. 7 and FIG. 7 are flowcharts for explaining the operation of one embodiment. FIG. 8 is a schematic diagram showing a cross section of the cable, and FIG. 9 is a diagram for explaining the configuration of the conventional device and the connection with the cable. 20 ... Cable connection tester, 21 ... Connector, 22 ... First switching circuit, 23 ... Second switching circuit, 24 ... Level detection circuit, 25 ... Third switching circuit, 26 ... Capacitance detection circuit,
27 crosstalk detection circuit, 28 determination means, 29
Storage means 32 switching control means;

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshinori Makito 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Teruyuki Takahashi 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Japan Nippon Telegraph and Telephone Corporation (72) Inventor Tokio Sato 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Hiroyoshi Okamoto 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph Within Telephone Co., Ltd. (72) Inventor Seiichi Nanjo 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Hisashi Ishii 1-16-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation In-house (56) Reference Literature 1-84072 (JP, U) (58) Field surveyed (Int.Cl. ⁶ , DB name) G01R 31/02

Claims (1)

(57) [Claims] 1. A cable connection tester which is connected to one end of a cable composed of a plurality of pairs of lines and performs a cross-connection, disconnection, or misplacement test on the cable with the other end of the cable being open. A DC signal of a predetermined level to a desired line, and a level detecting means for detecting the level of the line or another line; a cross-talk determining means for determining a cross-talk between lines based on a detection level from the level detecting means; Capacity detecting means for detecting the line capacitance of the line forming the pair of cables; disconnection determining means for determining disconnection of the line forming the pair based on the detected line capacitance; A crosstalk detecting means for providing a cross-talk of the signal on another paired line; Cabling tester, characterized in that a Irechigai determining means for determining Irechigai of emissions.