JP2021044759A - Deterioration detection device - Google Patents

Abstract

To provide a deterioration detection device capable of detecting deterioration of a coaxial cable and a terminating resistor.SOLUTION: A terminating resistor 2 is connected between a core wire 1a of a coaxial cable 1 and an outer skin ground wire 1b. A voltage generation source 10 applies a voltage between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b at the end of the coaxial cable 1 on the side where the terminating resistor 2 is not connected. A current monitor 11 measures the value of the current flowing through the core wire 1a, the outer skin ground wire 1b, and the terminating resistor 2 in a state where the voltage generation source 10 applies a voltage between the core wire 1a and the outer skin ground wire 1b. A deterioration detection unit 50 detects the deterioration of the coaxial cable 1 and the terminating resistor 2 on the basis of the value of the current measured by the current monitor 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a deterioration detection device that detects deterioration of a coaxial cable and a terminating resistor.

As a technique for detecting a disconnection of a coaxial cable, a DC voltage is applied between the core wire of the coaxial cable terminated by the terminating resistor and the outer skin ground wire, and the DC consisting of the core wire of the coaxial cable, the outer skin ground wire and the terminating resistor is applied. A technique is known in which a relay is operated by a current flowing through a loop and whether or not the relay is operating normally is detected to determine whether or not the coaxial cable is broken (for example, Patent Document 1 below). ..

Japanese Unexamined Patent Publication No. 62-15936

In the technique of Patent Document 1, it is possible to determine whether or not the coaxial cable is broken depending on whether or not the relay is operating normally. However, deterioration of the coaxial cable before the disconnection, such as an increase in the resistance value of the coaxial cable, cannot be detected, and it is difficult to prevent the coaxial cable from being disconnected.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a deterioration detection device capable of detecting deterioration of a coaxial cable and a terminating resistor.

The deterioration detection device according to the first aspect of the present invention is a deterioration detection device for termination resistance connected between the coaxial cable and the core wire of the coaxial cable and the outer skin ground wire, and is the termination resistance of the coaxial cable. At the end on the side where is not connected, a voltage generation source that applies a voltage between the core wire and the outer skin ground wire of the coaxial cable, and the voltage generation source is between the core wire and the outer skin ground wire. A current monitor that measures the value of the current flowing through the core wire, the outer skin ground wire, and the terminal resistor with the voltage applied to the cable, and the coaxial cable and the coaxial cable based on the current value measured by the current monitor. It is provided with a deterioration detection unit that detects deterioration of the terminal resistance.

The deterioration detection device according to the second aspect of the present invention is a deterioration detection device for the termination resistance connected between the coaxial cable and the core wire of the coaxial cable and the outer skin ground wire, and is the termination resistance of the coaxial cable. At the first end, which is the end on the side to which is not connected, a voltage generation source that applies a voltage between the core wire and the outer skin ground wire of the coaxial cable, and the voltage generation source is the core wire and the outer skin. A voltage monitor that measures the value of the voltage applied to the termination resistor with the voltage applied between the ground wire, and the coaxial cable and the termination resistor based on the voltage value measured by the voltage monitor. It is provided with a deterioration detection unit for detecting deterioration.

According to the present invention, when a voltage is applied between the core wire and the outer skin ground wire, the value of the current flowing through the core wire, the outer skin ground wire and the termination resistor, or the value of the voltage applied to the termination resistor can be determined. Since the state of the coaxial cable and the termination resistance is determined based on this, deterioration of the coaxial cable and the termination resistance can be detected.

It is a figure which shows the structure of the deterioration detection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the modification of the structure of the deterioration detection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the deterioration detection apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the modification of the structure of the deterioration detection apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the modification of the structure of the deterioration detection apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the deterioration detection apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows the modification of the structure of the deterioration detection apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows the structure of the deterioration detection apparatus which concerns on Embodiment 4 of this invention. It is a figure which shows the modification of the structure of the deterioration detection apparatus which concerns on Embodiment 4 of this invention.

<Embodiment 1>
FIG. 1 is a diagram showing a configuration of a deterioration detection device according to a first embodiment of the present invention. The deterioration detection device detects deterioration of the coaxial cable 1 and the terminating resistor 2 connected to the coaxial cable 1. A signal source 3 for inputting a communication signal to the coaxial cable 1 is connected to one end (first end) of the coaxial cable 1 via an AC coupler 4. The terminating resistor 2 is connected to the other end (second end) of the coaxial cable 1, and terminates the coaxial cable 1 by connecting between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b. ing. That is, the core wire 1a, the outer skin ground wire 1b, and the terminating resistor 2 of the coaxial cable 1 are connected in series. There is no limitation on the resistance value of the terminating resistor 2, and for example, 50Ω and 75Ω are common.

The deterioration detection device of the first embodiment includes a voltage generation source 10 and a current monitor 11 connected to an end of the coaxial cable 1 on the signal source 3 side (that is, an end on the side to which the terminating resistor 2 is not connected). A deterioration detection unit 50 that detects deterioration of the coaxial cable 1 and the terminating resistor 2 based on the output of the current monitor 11 is provided.

The voltage generation source 10 applies a constant DC voltage between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b at the end of the coaxial cable 1 on the signal source 3 side. The current monitor 11 measures the value of the current flowing through the series circuit including the core wire 1a, the outer skin ground wire 1b, and the terminating resistor 2 when the voltage generation source 10 applies a voltage between the core wire 1a and the outer skin ground wire 1b. To do. In the present embodiment, the current monitor 11 measures the current value at regular intervals.

The deterioration detection unit 50 detects the deterioration of the coaxial cable 1 and the terminating resistor 2 based on the current value measured by the current monitor 11. Here, the voltage applied by the voltage generation source 10 between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b is V, the resistance value of the core wire 1a of the coaxial cable 1 is R _1a , and the resistance value of the outer skin ground wire 1b is set. When R _1b, the resistance of the terminating resistor 2 and _{R 2,} the current value _{I M} is measured by the current monitor 11 _is expressed as _{I M = V / (R 1a} + R 1b + R 2). Therefore, the coaxial cable 1 or terminating resistor 2 is deteriorated, the resistance value R _1a of the core wire _1a, the resistance value R _1b of the outer skin ground line _1b, if any of the termination resistor 2 of the resistance value R ₂ is increased, the current value I _M decreases. Deterioration detecting unit 50, by detecting the change in the current value I _M, detecting the deterioration of the coaxial cable 1 and the terminating resistor 2. Therefore, the deterioration detection unit 50 can detect the deterioration of the coaxial cable 1 and the terminating resistor 2 before the coaxial cable 1 is broken or the terminating resistor 2 is damaged.

In the present embodiment, the deterioration detection unit 50 averages the current values measured by the current monitor 11 at regular intervals, and compares the current value (mean value) of the current cycle with the current value (mean value) of the previous cycle. When the amount of decrease from the previous cycle is larger than the predetermined threshold value, it is determined that the coaxial cable 1 or the terminating resistor 2 has deteriorated, and the operator of the coaxial cable 1 is notified to that effect. The deterioration detection unit 50 may determine that the coaxial cable 1 or the terminating resistor 2 has deteriorated when the amount of decrease in the current value from the initial value becomes larger than a predetermined threshold value.

In the present embodiment, the voltage applied by the voltage generation source 10 between the core wire 1a and the outer skin ground wire 1b is a DC voltage, but an AC voltage may also be used. When the voltage generation source 10 outputs an AC voltage, the frequency is not particularly limited as long as it does not depend on the frequency of the communication signal input from the signal source 3 to the coaxial cable 1 and its bandwidth. When the voltage generation source 10 outputs an AC voltage, the same effect as described above can be obtained.

Further, FIG. 1 shows a communication system in which only one coaxial cable 1 terminated by a terminating resistor 2 is used. However, as shown in FIG. 2, for example, a plurality of signal sources 3 are connected to the signal source 3 via a hybrid transformer 5 (FIG. 2). Then, two coaxial cables 1) may be connected. In this case, the voltage generation source 10 and the current monitor 11 are connected to the end of each of the plurality of coaxial cables 1 on the signal source 3 side. Further, the deterioration detection unit 50 determines the states of the plurality of coaxial cables 1 and the terminating resistors 2 based on the current values measured by each current monitor 11, and when deterioration is detected, the coaxial cable 1 is operated. Notify the person.

As described above, according to the deterioration detection device according to the first embodiment, the deterioration detection unit 50 detects the deterioration of the coaxial cable 1 and the terminating resistor 2 based on the current value measured by the current monitor 11, so that the coaxial cable 1 and the terminating resistor 2 are coaxial. Deterioration of the coaxial cable 1 and the terminating resistor 2 can be detected before the cable 1 is broken or the terminating resistor 2 is damaged.

<Embodiment 2>
FIG. 3 is a diagram showing a configuration of a deterioration detection device according to a second embodiment of the present invention. In FIG. 3, since the elements having the same functions as those shown in FIG. 1 are designated by the same reference numerals, detailed description thereof will be omitted.

The deterioration detection device of the second embodiment includes a voltage generation source 10 connected to an end of the coaxial cable 1 on the signal source 3 side (that is, an end on the side to which the terminating resistor 2 is not connected) and the coaxial cable 1. A voltage monitor 21 connected to the end of the terminating resistor 2 and a deterioration detecting unit 51 for detecting deterioration of the coaxial cable 1 and the terminating resistor 2 based on the output of the voltage monitor 21 are provided.

The voltage generation source 10 applies a constant DC voltage between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b at the end of the coaxial cable 1 on the signal source 3 side. The voltage monitor 21 measures the value of the voltage applied to the terminating resistor 2 in a state where the voltage generation source 10 applies a voltage between the core wire 1a and the outer skin ground wire 1b. In the present embodiment, the voltage monitor 21 measures the voltage value applied to the terminating resistor 2 at regular intervals.

Here, since the current monitor 11 and the deterioration detection unit 50 shown in FIG. 1 are provided at the end of the coaxial cable 1 on the signal source 3 side, it is easy to supply power to the current monitor 11 and the deterioration detection unit 50. However, since the voltage monitor 21 and the deterioration detection unit 51 of FIG. 3 are provided at the end of the coaxial cable 1 on the terminating resistor 2 side, it is necessary to separately prepare a power supply for driving them. For example, the power source for driving the voltage monitor 21 and the deterioration detection unit 51 may be obtained from the voltage applied to the terminating resistor 2, or the voltage monitor 21 and the deterioration detection unit 51 may be equipped with a battery or a solar panel as a power source. May be good.

The deterioration detection unit 51 detects the deterioration of the coaxial cable 1 and the terminating resistor 2 based on the voltage value measured by the voltage monitor 21. Here, the voltage applied by the voltage generation source 10 between the core wire 1a of the coaxial cable 1 and the outer skin ground wire 1b is V, the resistance value of the core wire 1a of the coaxial cable 1 is R _1a , and the resistance value of the outer skin ground wire 1b is set. When R _1b, the resistance of the terminating resistor 2 and _{R 2,} the voltage value _{V M} to be measured by the voltage monitor 21 _is expressed as _{V M = V × R 2 /} (R 1a + R 1b + R 2). Thus, for example, the coaxial cable 1 is deteriorated, the resistance value _{R 1b} of the resistance value _{R 1a} or the integuments ground line 1b of the core wire 1a is increased, the voltage value _{V M} decreases. Further, for example, the termination resistor 2 is deteriorated, the resistance value R ₂ of the terminating resistor 2 increases, the voltage value V _M increases. Deterioration detecting unit 51, by detecting the change in the voltage value V _M, detecting the deterioration of the coaxial cable 1 and the terminating resistor 2. Therefore, the deterioration detection unit 51 can detect the deterioration of the coaxial cable 1 and the terminating resistor 2 before the coaxial cable 1 is broken or the terminating resistor 2 is damaged. Also at that time, the degradation detection unit 51 can be a voltage value V _M depending rose or dropped, to determine which of the coaxial cable 1 or terminating resistor 2 is deteriorated.

In the present embodiment, the deterioration detection unit 51 averages the voltage value measured by the voltage monitor 21 at regular intervals, and compares the voltage value (average value) of the current cycle with the voltage value (average value) of the previous cycle. If the amount of decrease from the previous cycle is larger than the predetermined threshold value, it is determined that the coaxial cable 1 has deteriorated, and the operator of the coaxial cable 1 is notified to that effect. Further, if the amount of increase from the previous cycle is larger than a predetermined threshold value, the deterioration detection unit 51 determines that the terminating resistor 2 has deteriorated and notifies the operator of the coaxial cable 1 to that effect. The deterioration detection unit 51 may determine that the coaxial cable 1 or the terminating resistor 2 has deteriorated when the amount of increase or decrease of the voltage value from the initial value becomes larger than a predetermined threshold value. ..

Further, FIG. 3 shows a communication system in which only one coaxial cable 1 terminated by a terminating resistor 2 is used. However, as shown in FIG. 4, for example, a plurality of signal sources 3 are connected to the signal source 3 via a hybrid transformer 5 (FIG. 4). Then, two coaxial cables 1) may be connected. In this case, the voltage generation source 10 is connected to the end of each of the plurality of coaxial cables 1 on the signal source 3 side, and the voltage monitor 21 is connected to the end on the terminating resistor 2 side. Further, the deterioration detection unit 51 determines the state of each of the plurality of coaxial cables 1 and the terminating resistors 2 based on the voltage values measured by each voltage monitor 21, and when deterioration is detected, the coaxial cable 1 is operated. Notify the person to that effect.

Further, when each of the plurality of coaxial cables 1 is long and the installation locations of the voltage monitors 21 are separated from each other, one deterioration detection unit 51 may acquire the voltage values measured by the plurality of voltage monitors 21. It will be difficult. In that case, a deterioration detection unit 51 may be provided for each voltage monitor 21 as shown in FIG. However, it should be noted that since a plurality of deterioration detection units 51 are used, there is a problem that centralized management of the states of the plurality of coaxial cables 1 and the terminating resistor 2 becomes difficult.

As described above, according to the deterioration detection device according to the second embodiment, the deterioration detection unit 51 detects the deterioration of the coaxial cable 1 and the terminating resistor 2 based on the voltage value measured by the voltage monitor 21, so that the coaxial cable 1 and the terminating resistor 2 are coaxial. Deterioration of the coaxial cable 1 and the terminating resistor 2 can be detected before the cable 1 is broken or the terminating resistor 2 is damaged. Further, it is possible to determine whether the coaxial cable 1 or the terminating resistor 2 has deteriorated depending on whether the voltage value measured by the voltage monitor 21 has increased or decreased.

<Embodiment 3>
FIG. 6 is a diagram showing a configuration of a deterioration detection device according to a third embodiment of the present invention. The configuration of the deterioration detection device of FIG. 6 is a configuration in which a superimposition transmitting unit 31 and a superimposition receiving unit 32 are added to the configuration of FIG. 3, and the deterioration detection unit 51 is connected to the superimposing reception unit 32. In FIG. 6, since the elements having the same functions as those shown in FIG. 3 are designated by the same reference numerals, detailed description thereof will be omitted.

The superimposing transmission unit 31 is connected to the end of the coaxial cable 1 on the terminating resistor 2 side, and inputs voltage information, which is information on the voltage value of the terminating resistor 2 measured by the voltage monitor 21, to the coaxial cable 1. It is transmitted to the superimposition receiving unit 32. The voltage information signal output by the superimposed transmission unit 31 is superimposed on the communication signal output by the signal source 3 and the voltage output by the voltage generation source 10 in the coaxial cable 1.

The superimposition receiving unit 32 is connected to the end of the coaxial cable 1 on the signal source 3 side, and receives the voltage information input to the coaxial cable 1 by the superimposition transmitting unit 31. Not only the voltage information signal output by the superimposition transmitting unit 31 but also the communication signal output by the signal source 3 and the voltage output by the voltage generation source 10 are input to the superimposition receiving unit 32 from the coaxial cable 1. The superimposition transmission unit 31 extracts and receives the voltage information output by the superimposition transmission unit 31 from them.

The deterioration detection unit 51 determines the states of the coaxial cable 1 and the terminating resistor 2 based on the voltage information received by the superimposing transmission unit 31 (information on the voltage value of the terminating resistor 2 measured by the current monitor 11), and determines the state of the coaxial cable 1 and the terminating resistor 2. When the deterioration of 1 or the terminating resistor 2 is detected, the operator of the coaxial cable 1 is notified to that effect. The method of detecting the deterioration of the coaxial cable 1 and the terminating resistor 2 may be the same as that of the second embodiment, and the deterioration detecting unit 51 may detect the deterioration of the coaxial cable 1 and the terminating resistor 2 before the coaxial cable 1 is broken or the terminating resistor 2 is damaged. Deterioration of 2 can be detected. Further, as in the second embodiment, it is possible to determine whether the coaxial cable 1 or the terminating resistor 2 has deteriorated depending on whether the voltage value measured by the voltage monitor 21 has increased or decreased. ..

Further, FIG. 6 shows a communication system in which only one coaxial cable 1 terminated by a terminating resistor 2 is used. However, as shown in FIG. 7, for example, a plurality of signal sources 3 are connected to the signal source 3 via a hybrid transformer 5 (FIG. 7). Then, two coaxial cables 1) may be connected. In this case, the voltage generation source 10 and the superposed receiving unit 32 are connected to the end of each of the plurality of coaxial cables 1 on the signal source 3 side, and the voltage monitor 21 and the superposed transmitting unit 31 are connected to the end on the terminating resistor 2 side. To. Further, the deterioration detection unit 51 determines the state of each of the plurality of coaxial cables 1 and the terminating resistors 2 based on the voltage information received by each superimposition receiving unit 32, and when deterioration is detected, the deterioration detection unit 51 of the coaxial cable 1 Notify the operator to that effect.

In the present embodiment, the superimposing receiving unit 32 connected to the signal source 3 side of the coaxial cable 1 transmits voltage information from the superimposing transmitting unit 31, that is, information on the voltage value of the terminating resistor 2 measured by the voltage monitor 21. The deterioration detection unit 51 can be installed on the signal source 3 side of the coaxial cable 1 in order to receive the above. Therefore, for example, even when each of the plurality of coaxial cables 1 is long and the installation locations of the voltage monitors 21 are separated from each other, the voltage values measured by the plurality of voltage monitors 21 using one deterioration detection unit 51. Can be obtained. Therefore, even when the installation locations of the voltage monitors 21 are separated from each other, the plurality of coaxial cables 1 and the terminating resistors 2 can be centrally managed, and the problem described with reference to FIG. 5 does not occur.

As described above, according to the deterioration detection device according to the third embodiment, the same effect as that of the second embodiment can be obtained. Further, even when the installation locations of the voltage monitors 21 are separated from each other, the voltage values measured by the plurality of voltage monitors 21 can be acquired by using one deterioration detection unit 51, so that the plurality of coaxial cables 1 and the plurality of coaxial cables 1 can be obtained. The effect of enabling centralized management of the terminating resistor 2 can also be obtained.

<Embodiment 4>
FIG. 8 is a diagram showing a configuration of a deterioration detection device according to a fourth embodiment of the present invention. The configuration of the deterioration detection device of FIG. 8 is that the redundant signal generation unit 41 is provided in the superimposition transmitting unit 31 and the error detection unit 42 is provided in the superimposition receiving unit 32 with respect to the configuration of FIG. In FIG. 8, since the elements having the same functions as those shown in FIG. 6 are designated by the same reference numerals, detailed description thereof will be omitted.

The redundant signal generation unit 41 generates a redundant signal for error detection, and the superimposed transmission unit 31 adds the redundant signal generated by the redundant signal generation unit 41 to the voltage information and inputs it to the coaxial cable 1. Further, the error detection unit 42 detects an error (bit error) in the voltage information based on the redundant signal added to the voltage information received by the superimposed reception unit 32.

In the present embodiment, the redundant signal generated by the redundant signal generation unit 41 is used as a fixed signal pattern, and the superimposed transmission unit 31 adds a fixed signal pattern as a signal following the voltage information. In this case, the error detection unit 42 extracts the signal pattern following the voltage information received by the superimposition receiving unit 32, and determines whether or not a bit error has occurred depending on whether or not the extracted signal pattern matches a predetermined pattern. to decide. However, the redundant signal is not limited to a fixed signal pattern, and may be, for example, an error detection code such as a cyclic redundancy check signal calculated from voltage information or a parity bit, or a forward error correction code.

According to the deterioration detection device according to the fourth embodiment, the same effect as that of the third embodiment can be obtained, and the quality of communication between the superposed transmitting unit 31 and the superposed receiving unit 32 can be grasped. Therefore, it is possible to prevent erroneous detection of deterioration of the coaxial cable 1 and the terminating resistor 2 due to a bit error caused by, for example, an increase in the resistance value of the coaxial cable 1.

Further, FIG. 8 shows a communication system in which only one coaxial cable 1 terminated by a terminating resistor 2 is used. However, as shown in FIG. 9, for example, a plurality of signal sources 3 are connected to the signal source 3 via a hybrid transformer 5 (FIG. 7). Then, two coaxial cables 1) may be connected. In this case, the voltage generation source 10 and the superimposed receiving unit 32 (including the error detecting unit 42) are connected to the end of each of the plurality of coaxial cables 1 on the signal source 3 side, and the voltage monitor 21 is connected to the end on the terminating resistor 2 side. And the superimposed transmission unit 31 (including the redundant signal generation unit 41) is connected. Further, the deterioration detection unit 51 determines the state of each of the plurality of coaxial cables 1 and the terminating resistors 2 based on the voltage information received by each superimposition receiving unit 32, and when deterioration is detected, the deterioration detection unit 51 of the coaxial cable 1 Notify the operator to that effect.

In the present invention, each embodiment can be freely combined, and each embodiment can be appropriately modified or omitted within the scope of the invention.

1 Coaxial cable, 1a core wire, 1b outer skin ground wire, 2 terminating resistor, 3 signal source, 4 AC coupler, 5 hybrid transformer, 10 voltage source, 11 current monitor, 21 voltage monitor, 31 superimposition transmitter, 32 superimposition reception Unit, 41 redundant signal generation unit, 42 error detection unit, 50, 51 deterioration detection unit.

Claims (5)

A deterioration detection device for terminating resistance connected between a coaxial cable and the core wire of the coaxial cable and the outer skin ground wire.
At the end of the coaxial cable on the side where the terminating resistor is not connected, a voltage generation source that applies a voltage between the core wire and the outer skin ground wire of the coaxial cable, and
A current monitor that measures the value of the current flowing through the core wire, the outer skin ground wire, and the terminating resistor while the voltage generation source applies the voltage between the core wire and the outer skin ground wire.
A deterioration detection unit that detects deterioration of the coaxial cable and the terminating resistor based on the current value measured by the current monitor, and
Deterioration detection device. A deterioration detection device for terminating resistance connected between a coaxial cable and the core wire of the coaxial cable and the outer skin ground wire.
At the first end, which is the end of the coaxial cable on the side where the terminating resistor is not connected, a voltage generation source that applies a voltage between the core wire and the outer skin ground wire of the coaxial cable, and
A voltage monitor that measures the value of the voltage applied to the terminating resistor when the voltage source applies the voltage between the core wire and the outer skin ground wire.
A deterioration detection unit that detects deterioration of the coaxial cable and the terminating resistor based on the voltage value measured by the voltage monitor.
Deterioration detection device. A superposed transmission unit that inputs voltage information, which is information on the value of the voltage measured by the voltage monitor, to the coaxial cable from the second end, which is the end on the side to which the terminating resistor of the coaxial cable is connected. When,
A superimposing receiving unit that receives the voltage information input to the coaxial cable by the superimposing transmitting unit at the first end side of the coaxial cable.
With more
The deterioration detection unit detects deterioration of the coaxial cable and the terminating resistor based on the voltage information received by the superimposition receiving unit.
The deterioration detection device according to claim 2. The superimposed transmission unit includes a redundant signal generation unit that generates a redundant signal for error detection in the voltage information, and inputs the voltage information to which the redundant signal is added to the coaxial cable.
The superimposed receiving unit includes an error detecting unit that detects an error in the voltage information based on the redundant signal added to the received voltage information.
The deterioration detection device according to claim 3. The voltage generation source applies an AC voltage between the core wire of the coaxial cable and the outer skin ground wire.
The deterioration detection device according to any one of claims 1 to 4.

Images