JPH085695A - Electric tester for cable - Google Patents

Abstract

PURPOSE:To perform inspection, e.g. inter-pair short circuit or interphase short circuit, and conduction test of a cable using a tester having relatively simple structure. CONSTITUTION:The core 2A of a cable 1 to be tested is connected electrically with the fixed contacts 13A, 14A of two rotary switches 13, 14. When the movable contacts 13B, 14B of the rotary switches 13, 14 are connected with both terminals of a power supply section 15, all cores 2A are combined freely through switching operation of the rotary switches 13, 14 and connected with the power supply section 15. Consequently, both the inter-pair short circuit and interphase short circuit can be tested only through the operation of the rotary switches 13, 14. Conduction test can also be made when the other end of the cable 1 is connected with the terminal part for inter-pair short circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable electrical tester used for inspecting insulation between pairs or phases of multi-core cables and detecting breaks in core wires.

[0002]

2. Description of the Related Art A multi-core cable such as a communication cable or a control cable is subjected to various tests after production to confirm the insulation between the wires. FIG. 2 shows a side view of such a multi-core cable before the test. The cable under test 1
For example, it is composed of a multi-core cable such as a communication cable or a control cable. For one end, each core 2 is exposed for a predetermined length and a connector 3 is attached to one end thereof. Such a connector 3 is attached to the test apparatus, and a staff member operates a switch to perform a test while switching the connection circuit.

FIG. 3 is a schematic explanatory view of the test.
As shown in the figure, for example, a continuity test device 5 is connected to test whether or not the pair of core wires 2 are mutually short-circuited with each other. That is, the continuity test device 5 is connected to one end 2A of the pair of core wires 2 and the other end is opened to supply a test current to the core wires 2. As a result, if the core wires 2 are short-circuited to each other, for example, the lamp 6 lights up and the buzzer 7 sounds. To check whether or not the conductor of the core wire 2 is broken midway, the jumper wire 4 is connected to the other end 2B of the core wire 2 and a test current is supplied from the continuity test device 5. If the test current flows, the core wire 2 is normal, and if the test current does not flow, the core wire 2 is broken. This is also recognized by the lamp 6 and the buzzer 7.

[0004]

By the way, the above-mentioned conventional cable electrical test apparatus has the following problems to be solved. The conventional device has a configuration in which a large number of switches are used for electrical connection between each core wire and the continuity test device as described above, and a large number of lamps and buzzers are provided for performing continuity display and short-circuit display. However, in this case, the number of lamps and buzzers that influence the reliability of the test is too large, and the maintenance and inspection thereof becomes complicated. In the case of a continuity test, etc., the connector 3 of the cable under test 1 shown in FIG.
A complicated work of electrically connecting or disconnecting the core wires on the side not connected with each other is required.

The present invention has been made in order to solve the above-mentioned problems, and an electrical test of a cable can be carried out quickly and reliably by a device having a relatively simple structure, such as a pair-to-pair short circuit, a short circuit between phases, or a continuity test. The purpose is to provide a device.

[0006]

The cable electrical test apparatus of the present invention is electrically connected to the conductor of each core wire of the cable under test through a detachable connector and has a terminal corresponding to each core wire. A terminal part, a power supply part for supplying a test current to the conductor of each core wire of the cable under test, a display connected to the power supply part in series for detecting and displaying the presence or absence of the flow of the test current, respectively. A rotary switch having a fixed contact electrically connected to each terminal of the terminal portion and a movable contact for selecting a core wire for supplying the test current is provided.
One of the rotary switches has a movable contact connected to one output terminal of the power supply unit, and the other rotary switch has a movable contact connected to the other output terminal of the power supply unit. It is a thing.

[0007]

This device electrically connects the core wire of the cable under test to the fixed contacts of the two rotary switches. When both terminals of the power supply unit are connected to the movable contact of the rotary switch, all the core wires are freely combined with each other and electrically connected to the power supply unit by the switching operation of the rotary switch. This allows both pair-to-pair and phase-to-phase short circuits to be tested simply by operating the rotary switch. A continuity test can also be performed by connecting the other end of the cable under test to a terminal portion for short-circuiting between pairs.

[0008]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a connection diagram showing an embodiment of a cable electrical test apparatus of the present invention. This device is suitable for conducting a continuity test or a short circuit test on a multi-core cable having a structure as shown in FIG. 2, for example. In the case of the present invention, the cable under test 1 shown in FIG.
It is assumed that the same connector 3 as shown in FIG. Then, one of the connectors is connected to the terminal portion 11 shown in FIG.

For example, when there are ten core wires 2A as shown in this figure, the terminal portion 11 is provided with the number of terminals electrically connected to each of the ten core wires 2A. Each of these terminals is provided with two rotary switches 1
The ten fixed contacts 13A and 14A of 3 and 14 are associated and electrically connected. Therefore, 20 lead wires 12 are provided and 10 lead wires are provided for the rotary switch 13.
Of the fixed contacts 13A of the rotary switch 14 and the other of the fixed contacts 14A of the rotary switch 14.

In addition to this, a power supply section 15 for supplying a test current to the cable under test 1 is provided. The power supply unit 15 includes a battery 16, a switch 17, a check lamp 21, a resistor 22, a pilot lamp 23,
A resistor 24 and a buzzer (BZ) 25 are provided.
One output terminal of the power supply unit 15 is electrically connected to the movable contact 13B of the rotary switch 13, and the other output terminal is electrically connected to the movable contact 14B of the rotary switch 14. A resistor 22, a check lamp 21, a battery 16 and a switch 17 are inserted in series between the two output terminals of the power supply unit 15. Further, a buzzer 25 is inserted between the two output terminals of the power supply unit 15. Further, a series circuit of a resistor 24 and a pilot lamp 23 is connected in parallel with the battery 16 and the switch 17. In the present invention, the check lamp 21 and the buzzer 25 provided in the power supply unit are called an indicator.

The circuit as described above is housed in a box 30 having a structure as shown in FIG. That is, this box 3
0 has a handle 31 attached to the side surface so that it can be carried. Further, two rotary switches 13 and 14 are arranged on the front surface. Further, a check lamp 21, a pilot lamp 23 and a buzzer 25 are provided so that the test result can be monitored while operating the rotary switch.
Is located on the front panel. Furthermore, the handle 31
A switch 17 is attached to the panel on the side where the is attached, and an on / off operation is performed for each inspection. Furthermore, a terminal portion 11 is provided on the opposite side panel. The connector 3 of the cable under test 1 is attached here.

In addition to this, the apparatus is provided with a terminal portion 11 * for pair-to-pair short circuit in addition to the terminal portion 11 for the continuity test. FIG. 5 shows a wiring diagram of such a terminal portion 11 *. As shown in this figure, the terminals of the terminal portion 11 * are short-circuited by the jumper wires 4 to each other in a pair of terminals inside the box 30.
This is used to short between pairs on the opposite side of the cable under test as previously described with reference to FIG.

FIG. 6 shows a connection diagram for explaining the operation principle of the above-mentioned device. For example, focusing only on the pair of core wires of the cable under test 1, the output terminal of the power supply unit 15 is connected to the one end 1A of the cable under test 1 as shown in this figure. Also, in the continuity test, the jumper wire 4 is connected to the other end 1B of the cable under test 1.

First, considering the case where the jumper wire 4 is not provided, the power supply section 15 is connected to one end 1 of the cable under test 1.
Even when electrically connected to A, the test current does not flow from the power supply unit 15. In this case, when the switch 17 is closed, the check lamp 21 and the resistor 2 are caused by the electromotive force of the battery 16.
An electric current flows through a circuit connecting the 2 and the buzzer 25. Therefore, even if the core wire is not connected, the buzzer 25 sounds when there is no pair-to-pair short circuit in the core wire. Further, the check lamp 21 is slightly darkened due to the voltage drop caused by the resistor 22 and the buzzer 25. At this time, the resistor 2
4 and the pilot lamp 23 also carry the current from the battery 16. Therefore, every time the switch 17 is turned on, the pilot lamp 23 is lit with a constant brightness.

In the case of the device of this embodiment, the pilot lamp 23 has the battery 16 when the switch 17 is turned on.
Is provided to check if there is power to supply the current required for the test. On the other hand, when the cores of the cable under test 1 are short-circuited to each other, the output terminals of the power supply section 15 are electrically connected with very low resistance. In this case, the voltage applied to both ends of the buzzer 25 becomes extremely small, so that the buzzer 25 does not ring. Also, since the buzzer 25 is not inserted in the circuit, the check lamp 2
1 lights up brighter. The operation of the pilot lamp 23 does not change.

That is, when the core wires of the cable under test 1 are short-circuited to each other, the check lamp 21 is brightly lit and the buzzer 25 does not sound. The same phenomenon occurs when the jumper wire 4 is connected to the other end of the core wire and forcedly short-circuited. The same thing occurs when a phase-to-phase short circuit occurs between a certain core wire and another core wire. In the above embodiment, even in this case, the phenomenon can be detected by the check lamp 21 or the like.

FIG. 7 is an explanatory diagram summarizing the above operation. As shown in this figure, when the pair-to-pair open circuit is tested for pair-to-pair short-circuit or phase-to-phase short-circuit, first, for example, the movable contact 13B of the rotary switch 13 shown in FIG. 1 is connected to the first terminal. The movable contact 14B of the rotary switch 14 is also connected to the same first terminal. After that, the movable contact 13B of the rotary switch 13 is left as it is, and the movable contact 14B of the other rotary switch 14 is moved to the second and third positions.
The connection is switched to another fixed contact in the order of the 4th, 10th, etc. In this way, a short circuit between the core wire connected to the first fixed contact and all other core wires can be searched for. After that, the movable contact 13B of the rotary switch 13 is operated to electrically connect to the second core wire next.
Then, again, the movable contact 14B of the rotary switch 14 is sequentially scanned from the first terminal to the tenth terminal. This makes it possible to perform pair-to-phase and phase-to-phase short circuit inspection for all core wire combinations. By performing such an operation by combining two rotary switches and performing the operation as described above, the circuit itself can be simplified, and quick and reliable processing can be performed.

As a result, as shown in the explanatory view of FIG. 7, in the inspection with the pair open, if the insulation is normal, the buzzer sounds and the check lamp is dark. If there is a short circuit, the buzzer will not sound and the check lamp will be bright. On the other hand, when the connector at the other end of the cable under test 1 is connected to the terminal portion 11 * shown in FIG. 5 so that the opposite end is short-circuited between the pair, the buzzer does not sound and the check lamp lights bright. If the core wire is broken, the buzzer sounds and the check lamp is dark. Of course, the brightness of the pilot lamp does not change, and the pilot lamp always lights during inspection work. The same applies to the phases.

With the above-mentioned structure, it is possible to carry out a pair-to-pair short circuit, a phase short circuit, a continuity test, etc. by a large number of combinations of core wires using one check lamp and two rotary switches. Therefore, it is possible to automatically perform the switching operation of the rotary switch as described above and perform the electrical test in a short time. Further, if the terminal portion for short-circuiting between the pair is provided, the treatment of the other end of the cable becomes extremely easy. In addition, the test connector as described above,
By adopting the so-called batch connection method, it can be attached to the end of the cable relatively easily. Therefore, the test time can be extremely shortened as a whole.

The present invention is not limited to the above embodiments. The configuration of the connector and the number of core wires can be freely selected.
In addition, the power supply unit was configured to include a check lamp, pilot lamp, and buzzer, but a buzzer is not necessary when checking only with eyes, and there is a means to check whether the power supply source such as a battery is normal. Otherwise, no pilot lamp is needed. Further, the rotary switch may be a mechanical switch, or may be a switch that electrically switches circuits based on the same principle.

[0021]

The cable electrical test apparatus of the present invention described above is electrically connected to the conductor of the core wire of the cable under test through the detachable connector, and has a terminal portion having terminals corresponding to the respective core wires. , A power supply unit that supplies a test current to the conductor of each core of the cable under test, an indicator that is incorporated in the power supply unit and that detects and displays the presence or absence of a test current flow, and each terminal of the terminal unit Has two rotary switches each having a fixed contact electrically connected thereto and a movable contact for selecting a core wire for supplying the test current, and the movable contact of one rotary switch is one of the power supply units. Since it is connected to the output terminal and the movable contact of the other rotary switch is connected to the other output terminal of the power supply section, the multi-core cable can be operated by simple operation of the rotary switch using a simple indicator. Pairs short, phase short can easily perform a continuity test or the like. If a jumper wire that short-circuits each pair of cores of the cable under test is connected between the corresponding terminals, the other end of the cable under test can be attached to this terminal to easily conduct electricity. The test can be conducted.

[Brief description of drawings]

FIG. 1 is a connection diagram showing an embodiment of a cable electrical test apparatus of the present invention.

FIG. 2 is a side view when a connector is connected to a conventional cable under test.

FIG. 3 is a wiring diagram showing a conventional cable testing device.

FIG. 4 is an external perspective view showing a cable electrical test apparatus of the present invention.

FIG. 5 is a connection diagram of a terminal portion for pair-to-pair short circuit provided in the device of the present invention.

FIG. 6 is a circuit diagram illustrating the operating principle of the device of the present invention.

FIG. 7 is an explanatory diagram showing the operation of the display unit in each state of the device of the present invention.

[Explanation of symbols]

 1 Cable to be tested 2A Core wire 11 Terminal part 13,14 Rotary switch 13A, 14A Fixed contact 13B, 14B Movable contact 15 Power supply part 17 Switch 21, 23, 25 Indicator

Claims (2)

[Claims] 1. A terminal portion electrically connected to a conductor of each core wire of the cable under test through a detachable connector and having a terminal corresponding to each core wire, and a conductor of each core wire of the cable under test. A power supply unit that supplies a test current to the power supply unit, a display unit that is connected in series to the power supply unit and that detects and displays the presence or absence of a test current flow, and is electrically connected so as to correspond to each terminal of the terminal unit. There are two rotary switches each having a fixed contact and a movable contact for selecting the core wire for supplying the test current, and the movable contact of one rotary switch is connected to one output terminal of the power supply unit and the other of the rotary switches. An electrical testing device for a cable, wherein a movable contact of the rotary switch is connected to the other output terminal of the power supply section. 2. A terminal part is provided, in which jumper wires for short-circuiting each pair of core wires of the cable under test are connected between corresponding terminals, and the other end of the cable under test is attachable to and detachable from this terminal part. The cable electrical test device according to claim 1, wherein the electrical test device is electrically connected via a connector.