JPS59167137A - Tester for trouble of input and output circuit - Google Patents

Abstract

PURPOSE:To attain a simple tester which has a function to locate a device the point occurring a trouble by measuring the voltage of an output circuit or the impedance of an input circuit of each device to detect the occurrence of the trouble if the trouble occurs in one of devices connected to one another by input/output circuits. CONSTITUTION:An output circuit 5 is connected to a tester 3 through a cable 4 and a connector 7. In the tester 3, the output circuit 5 is connected to an output circuit measuring circuit 9 by a contact S1a of a switch 8 and is connected to a diode 13 and an ammeter 12 through a contact S2a of a switch 15. Then, a closed circuit passing a switch S3, the contact S2b of the switch 15, and a ground line SG and reaching said output circuit 5 is constituted. At this time, though a light emitting diode 11 is connected also, the circuit is broken by the light emitting diode 11 itself because the polarity of the potential is opposite to the polarity of the light emitting diode 11. That is, even if the output polarity of the output circuit 5 is uncertain, at a measurement time, the output state of the output circuit 5 is measured by the deflection of a needle of the ammeter 12 and the light emission of the light emitting diode 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an input/output circuit failure tester, which is particularly necessary when transmitting data using a communication line.

This invention relates to a simple input/output circuit fault tester suitable for determining which of the above devices is at fault when a fault occurs between a modem, network control device, data terminal device, etc. It is.

[Prior art]

A so-called modem tester is conventionally known as a tester for modulation/demodulation equipment, network control equipment, etc.

The modem tester is a tester that uses an AClooV commercial power source, and has functions such as measuring the characteristics of an electric circuit and measuring the gain of a communication line.

At the beginning of business, such as when a communication line is opened, it is necessary to perform six measurements and tests using the modem tester mentioned above. can be difficult to handle. That is,
As a power source, a commercial AClooV power source is required, and the modem test voice itself is large and expensive, and it is not possible to provide a large number of them.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and the purpose of t is to provide a function to isolate which of the above devices is at fault when a fault occurs between various devices that perform data transmission. An object of the present invention is to provide a simple input/output circuit fault tester having the following features.

[Summary of the invention]

The key point of the present invention is that when a failure occurs in any of the devices connected to the roof tiles, the input/output circuit is configured to express the binary values of 1" and OIT using + and - potentials. Detection is performed by measuring the voltage of the output circuit of each device or the impedance of the 11 input paths. It is used by connecting.

[Embodiments of the invention]

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

Figure 1 is a diagram showing an outline of a normal connection situation between a modulation/demodulation device 1 and a network control device 2, which is an example of the application of the input/output circuit fault tester (hereinafter simply referred to as "tester") of the present invention. ,
0 is a diagram showing an overview of the test status of the network control device 2, and 5 is a diagram showing an outline of the test situation of the variable m device 1.
Further, 4 indicates connection cables. FIG. 2 shows details of the connection status between the modulation and demodulation device 1 and the network control device 2. As shown in FIG. In the figure, 5.6 is JI
An output circuit and an input circuit having electrical characteristics specified in S-C6361 (1971) are shown.

The connection cable 4 is used for connection completion (hereinafter referred to as "DSC") and line connection command (
(hereinafter referred to as “CML”) and call indication (hereinafter referred to as “CI
''), circuits T and R that transmit to the two decorated communication lines, and a ground line (S).
G) has each signal line.

The circuit under test that is the object of the tester shown in this embodiment is an input/output circuit for the five signals DSC, CML, and CI, and a closed circuit is formed using these and the ground MSG. Incidentally, as shown in FIG.
Enter I. Conversely, the network control device 2 outputs the signals DSC and CI, and inputs the signal CML.

The above-mentioned input/output circuit, which is the target of the tester shown in this example, is configured so that the two values of 'l''° and nO++ are expressed by negative potentials. If this occurs, the above-mentioned + and - polarities cannot be reversed, and what should be a medium potential becomes two potentials, or vice versa, resulting in an incorrect state.

Possible causes of this are that the output circuit is not outputting a specified voltage or that the impedance of the input circuit is not within the specified range. Therefore, the tester shown in this embodiment is configured to have the following four functions. - α) Negative potential measurement of the output voltage of the circuit under test? ) Measuring the positive potential of the output voltage of the circuit under test (5) Measuring the input impedance of the circuit under test ←) Measuring the potential of the tester power supply As shown in FIG. It's going to be a good thing. - Fig. 3 shows a specific configuration of a tester that is an embodiment of the present invention. In Figure 3, 7
is the connector "1 &' connected to the cable 4
Slb” 1° is a contact point of a switch 8 for switching the connected signal to an output circuit measurement circuit 9 and an input circuit measurement circuit 10, which will be described later.The output circuit measurement circuit 9 is connected to resistors R,,R. , and by the light emitting diode r11.

(partially omitted in the figure), and the input circuit measuring circuit 10 is composed of a resistor R3 (partially omitted in the figure).

Further, 12 is a DC ammeter (hereinafter simply referred to as "ammeter"), 13 is a polarity protection diode, and 5fia'
"Sb is a contact point of a switch 15 that controls the connection of the output circuit measurement circuit 9 to the ground 1sSG via the ammeter 12. The switch 15 also connects the input circuit measurement circuit 10 to the ground 1sSG via the ammeter 12. The switch 15 controls the connection to the dry battery power source 16 to form a closed circuit including the dry battery power source 16, the ammeter 12, and the resistor R4.S8 is a push button switch for carrying out the measurement. be.

The operation of the tester of this embodiment configured as described above will be explained below.

FIG. 4 is a diagram showing a situation in which the output circuit 5 of the signal CML of the network control device 2 is measured, and corresponds to () in FIG. Output circuit 5 is connected to cable 4. : Connected to the tester 3 via the I connector 7. Test device.

3 is connected to the output circuit measuring circuit 9 through the contacts S1& of the switch 8, and is further connected to the diode 13.3 through the contacts S, & of the switch 15. Connected to ammeter 12. Then, via the switch S8, the contact S of the switch 15,
b. A closed circuit is formed that connects to the output 1 circuit 5 via the ground line SG. At this time, the light emitting diode 11 is also connected, but since the polarity and the positive and negative potentials of the light emitting diode 11 are opposite, the circuit is interrupted by the light emitting diode 11 itself.

When the switch S8 is closed in this state, a current flows through the ammeter 12, and the negative potential of the output circuit 5 represented by V -R,1...α) can be measured.

FIG. 5 shows a state in which the same closed circuit as in FIG. 4 is constructed, and the output circuit 5 is at a positive potential. In this case, the circuit to the ammeter 12 is cut off by the diode 13, but since the polarity matches that of the light emitting diode 11, if the current flowing through the light emitting diode 11 is 1, then V+-R11...(2) Therefore, even if the positive potential of the output circuit 5 is higher than the specified value, the four light emitting diodes 11 will emit light.

That is, even if the output polarity of the output circuit 5 is undefined during measurement, a closed circuit as shown in FIGS. This means that the output state of the circuit 5 can be measured. Further, the signal CML can be reversed between positive and negative by operating a switch in the network control device 2.
It can also be confirmed by the change in the light emitting state.

FIG. 6 is a diagram showing a situation in which the impedance of the input circuit is measured, and corresponds to FIG. 1 (0). Since the input circuit 6 for the signal CML is within the modulation/demodulation device 1,
The connections are made as shown in FIG. 6, the switch 8 is inverted, and the switch 15 is also switched to the position for input measurement of the signal CML.

Input circuit 6 is made of Chemipur 4. Tester 3 via connector 7
In the tester 3, power is supplied from the dry cell power supply 16, and through the contact Stb of the switch 15, the switch S8.current 1#t12, the diode 13.contact s, IL'.

A closed circuit I# is formed via the resistor R8 and the contact 511L of the switch 8, and the input circuit is formed by the formula shown below.

6 impedances can be measured.

γ-E/1-R8...0 FIG. 7 shows a situation in which it is measured whether the power supply voltage of the tester 3 is within the specified range or not. In this case, by switching the switch 15 to the measurement position, E-R,i...(1
), the voltage E of the dry battery power supply 16 can be measured.

In the above embodiment, the switching of the input/output circuit of the signal CML was mainly explained in the case of measurement, but the switching of the switch 8 and the switch 15 is done in exactly the same way for the input/output circuit of the other signals DSC and CI. It is clear that the electrical characteristics of each circuit can be measured one by one using the following method.

Furthermore, the present invention is applicable not only to fault tests between the modem and network control equipment shown in the above embodiments, but also to fault tests between various devices that transmit data using input/output circuits as described above. Needless to say, it is possible.

〔Effect of the invention〕

As described above, according to the present invention, the two values "l" and °°0"', which are composed of an ammeter, a resistor, two light-emitting diodes, a DC power supply, and a switch that controls the connection of these, are
, -In a fault tester for input/output circuits configured as <WIt, the output is determined by switching the switch for each circuit under test and measuring the current flowing through the resistor using the power supply phase. The circuit voltage, the impedance of the input circuit, and the power supply voltage of the tester itself are measured, and the polarity of the output circuit is determined based on the presence or absence of light emission depending on the polarity of the light emitting diode. This has the remarkable practical effect of realizing a simple test device that can determine which of the devices is at fault when a fault occurs between various devices.

[Brief explanation of drawings]

FIG. 1(A) is a diagram showing an overview of a data transmission system targeted by the present invention, FIG. FIG. 3 is a diagram showing details of the connection status between the modem and network control equipment, FIG. 3 is a diagram showing a specific configuration example of a tester that is an embodiment of the present invention, and FIGS. 4 to 7 are diagrams showing examples of measurement situations. 1: Modulation/demodulation device, 2: Network control device, 3: Test device, 4: Connection cable, 5: Output circuit, 6: Input circuit, 7: Connector, 8.15: Switch, 9: Output circuit Measurement circuit, 1
0: Input circuit measurement circuit, 11.: Light emitting diode, 1
2: Ammeter, 13: Diode, 16: Dry battery power supply, S
, :Push button switch O 1st Figure 2 2nd Figure □ / 3rd Figure

Claims (1)

[Claims] U
In a fault tester for input/output circuits configured to express binary values of 11 and °°0'' with + and - potentials, the switch is switched for each circuit under test to measure the current flowing through the resistor. By measuring with said ammeter,
An input/output device characterized in that it is configured to measure the voltage of the output circuit, the impedance of the input circuit, and the power supply voltage of the tester itself, and to determine the polarity of the output circuit based on the amount of light emitted depending on the polarity of the light emitting diode. Circuit 1 fault tester.