Communication cable detection device

Abstract

The utility model relates to a communication cable detection device, which comprises a detection active end device and a detection passive end device, the detection active end device and the detection passive end device are sequentially connected through a communication cable to be detected, and the detection active end device sequentially sends detection signals to the detection passive end device through core wires of the communication cable to be detected; the detection active device comprises a signal generator and a signal transmitter; the detection device comprises a signal receiving device and an indicating device. And the signal transmitter for detecting the active device further comprises a self-protection device for continuously transmitting a detection signal after the signal generator stops working. According to the utility model, the on-off of the communication line can be detected, and whether the conduction quality of the communication joint and each wire core is stable and reliable can be detected. Therefore, sudden faults caused by unreliable communication network cable conduction quality can be rapidly and accurately checked, and safe operation of equipment is guaranteed.

Description

Technical Field

[0001] The utility model relates to a communication cable detection device. Background Art

[0002] In the field of industrial automatic control, Ethernet communication or improved Ethernet communication protocols are increasingly used as signal transmission protocols for industrial automatic control. Currently, common industrial Ethernets include Ethernet, PROFINET, CC-Link, etc. Compared with the Ethernet used for the Internet, the Ethernet used for industrial automatic control pays more attention to the real-time performance and stability of signal transmission, and has relatively strict requirements for communication delay and packet loss. Therefore, the quality of network cables used for industrial control is often required to be relatively high. In addition to having thicker wire cores and stronger connectors, they often also include thick shielding wires. Despite this, the phenomenon of occasional poor contact or momentary open circuit cannot be completely eliminated in these excellent network cables. Especially when the equipment has been running for a certain number of years, the problems of these communication network cables will gradually emerge, posing a hidden danger to the safe operation of the equipment. Of course, when these defects of the network cables exist in the system, they may not necessarily cause a failure immediately, but may suddenly occur under a certain specific period or working condition, such as vibration at a certain frequency, resulting in the interruption of machine operation or system abnormality. When engineering technicians arrive at the scene to start troubleshooting, the system automatically returns to normal. Looking at the numerous network cables, it is not known which one is faulty, which greatly troubles the maintenance personnel. And ordinary network cable detectors are difficult to detect such defects in network cables. Such failures caused by the conduction quality of communication network cables pose a hidden danger to the safe operation of the equipment and bring difficulties to equipment maintenance. Summary of the Utility Model

[0003] The utility model provides a communication cable detection device, which can not only detect the continuity of communication lines, but also detect whether the conduction quality of communication connectors and each wire core is stable and reliable. So as to quickly and accurately troubleshoot sudden failures caused by unreliable conduction quality of communication network cables and ensure the safe operation of equipment.

[0004] The technical solution of the utility model is: a communication cable detection device, including a detection active end device and a detection passive end device, the detection active end device and the detection passive end device are sequentially connected by a to-be-detected communication cable, and the detection active end device sequentially sends detection signals to the detection passive end through each core wire of the to-be-detected communication cable;

[0005] The host includes: a pulse signal generator for generating detection signals, a signal transmitter for sending the detection signals to each core wire of the to-be-detected communication cable, and an indicating device for respectively indicating successful signal transmission;

[0006] The auxiliary machine described above includes: a signal receiving device that respectively receives detection signals through each core wire of the communication cable to be tested, and an indicating device that respectively indicates the signal states received from each core wire of the communication cable to be tested.

[0007] In the signal transmitter of the main machine described above, there is also a self-holding device that continues to send detection signals after the signal generator stops working.

[0008] Furthermore, in the communication cable detection device described above:

[0009] The communication cable to be tested is a cable with 8 core wires and an external shielding layer G, and has cable connectors at both ends;

[0010] The signal transmitter includes a sending end, and the sending end is an RJ45 socket. Through this socket, the shielding layer G of the 8-core cable is connected to the negative pole of the main machine;

[0011] The signal receiving device includes a receiving end, and the receiving end is an RJ45 plug; the indicating device is LED indicators L11 - L18 connected between each core wire of the RJ45 plug and the shielding layer G.

[0012] Furthermore, in the communication cable detection device described above: the signal generator includes a pulse generator and a decimal counter. The pulse output end of the pulse generator is connected to the CLK end of the decimal counter, and the Y0 - Y7 of the output end of the pulse generator are respectively connected to the 1 - 8 pins of the RJ45 socket at the sending end.

[0013] Furthermore, in the communication cable detection device described above: the chip model of the decimal counter is the 4017 chip.

[0014] Furthermore, in the communication cable detection device described above: the chip model of the pulse generator is the NE555 chip.

[0015] Furthermore, in the communication cable detection device described above: the self-holding device includes relays K1 - K8 respectively arranged on the connection lines connecting Y0 - Y7 of the output end of the pulse generator to the 1 - 8 pins of the RJ45 socket; one end of the electromagnetic coils of the relays K1 - K8 are respectively connected to Y0 - Y7 of the output end of the pulse generator, and the other ends are respectively connected to the 1 - 8 pins of the RJ45 socket; the normally open contacts of the relays K1 - K8 are respectively connected to Y0 - Y7 of the output end of the pulse generator, and the other contacts are respectively connected to the positive pole of the power supply.

[0016] Furthermore, in the communication cable detection device described above: LED indicators L1 - L8 are also connected in series between Y0 - Y7 of the output end of the pulse generator and the 1 - 8 pins of the RJ45 socket.

[0017] Further, in the above communication cable detection device: it further includes shunt resistors R1-R8 and shunt resistors R11-R18; the shunt resistors R1-R8 are respectively connected in parallel with the LED indicators L1-L8, and the shunt resistors R11-R18 are respectively connected in parallel with the LED indicators L11-L18.

[0018] Further, in the above communication cable detection device: the resistance of the electromagnetic coils of the relays K1-K8 is much greater than the resistance of each core wire of the communication cable to be tested, and the resistance value after the shunt resistor and the LED lamp are connected in parallel should be equivalent to the resistance value of the relay electromagnetic coil.

[0019] The utility model can not only detect the on-off of the communication line, but also detect whether the conduction quality of the communication joint and each wire core is stable and reliable. So as to quickly and accurately troubleshoot the sudden faults caused by the unreliable conduction quality of the communication network cable and ensure the safe operation of the equipment.

[0020] The following will describe the present utility model in detail with reference to the accompanying drawings and specific embodiments. Description of the Drawings

[0021] Figure 1 is the circuit schematic diagram of the communication cable detection device in Embodiment 1 of the present utility model;

[0022] Figure 2 is the external view of the detection active end device of the communication cable detection device in Embodiment 1 of the present utility model;

[0023] Figure 3 is the external view of the detection passive end device of the communication cable detection device in Embodiment 1 of the present utility model. Detailed Embodiment

[0024] This embodiment is a communication cable detection device that can be used to detect an eight-core communication cable, including a detection active end device (host) and a detection passive end device (slave). The detection active end device and the detection passive end device are sequentially connected by the communication cable to be tested. The detection active end device sequentially sends detection signals to the detection passive end through each core wire of the communication cable to be tested; the communication cable detection device of this embodiment can respectively detect each core wire in the eight-core cable. In practice, the cable to be detected is an eight-core cable, and there is an RJ45 connector at each end of the 8-core cable, and both are RJ45 male connectors (plugs). Therefore, in this embodiment, sockets are provided on the detection active device (host) and the passive device (slave) with a housing.

[0025] In this embodiment, as Figure 1As shown in the figure, the active detection device includes: a signal generator that generates a detection signal, and a signal transmitter that sends the detection signal to each core wire of the communication cable to be tested. Here, the signal transmitter has at least 8 signal-sending pins, and each signal-sending pin corresponds to the communication cable to be tested (8-core cable) and independently sends the electrical signal generated by the signal generator to each core wire of the 8-core cable.

[0026] The passive detection device includes: a signal receiving device that receives the detection signal through each core wire of the communication cable to be tested, and an indicating device that respectively indicates the signal status received from each core wire of the communication cable to be tested. Here, the receiving device can respectively receive the signals from each core wire of the 8-core cable and respectively indicate them to the indicating device. In this way, each core wire in the communication cable can be detected simultaneously or non-simultaneously during detection.

[0027] In this embodiment, the signal transmitter of the active detection device further includes a self-holding device that continues to send the detection signal after the signal generator stops working. In this way, continuous detection of each core wire can be maintained.

[0028] In this embodiment, the communication cable to be tested is a cable with 8 core wires and an external shielding layer G, as Figure 1 shown: 2 is the cable to be tested with cable connectors at both ends. The signal transmitter includes a sending end 1, and the sending end 1 is an RJ45 socket, which connects the shielding layer G of the 8-core cable to the negative pole of the active detection device.

[0029] The signal receiving device described above includes a receiving end 3, and the receiving end 3 is an RJ45 socket; the indicating device is LED indicators L11-L18 connected to each core wire and the shielding layer G of the RJ45 plug.

[0030] In this embodiment, as Figure 1 shown: The signal generator includes a pulse generator and a decimal counter. The pulse output end of the pulse generator is connected to the CLK end of the decimal counter. The Y0-Y7 of the output end of the pulse generator are respectively connected to the 1-8 pins of the RJ45 socket of the sending end 1. The chip model of the decimal counter is the 4017 chip. The chip model of the pulse generator is the NE555 chip.

[0031] In this embodiment, the self-protection device includes relays K1 - K8 which are respectively arranged on the connection lines connecting Y0 - Y7 at the output end of the pulse generator to pins 1 - 8 of the RJ45 socket; one ends of the electromagnetic coils of the relays K1 - K8 are respectively connected to Y0 - Y7 at the output end of the pulse generator, and the other ends are respectively connected in series with indicator lights L1 - L8 and then connected to pins 1 - 8 of the RJ45 socket; the normally open contacts of the relays K1 - K8 are respectively connected to Y0 - Y7 at the output end of the pulse generator, and the common contacts are connected to the positive pole of the power supply through K0 and K. It also includes shunt resistors R1 - R8 and shunt resistors R11 - R18; the shunt resistors R1 - R8 are respectively connected in parallel with L1 - L8, and the shunt resistors R11 - R18 are respectively connected in parallel with L11 - L18. The communication cable detection device of this embodiment includes a main unit and a sub-unit. The connectors of the communication cable to be tested are respectively plugged into the main unit and the sub-unit of this device. Attached Figure 2 is the external shape of the main unit, Figure 3 is the external shape of the sub-unit. The main unit is composed of a housing, an internal circuit and an RJ45 socket. The main unit panel includes a power switch (Off / On), a toggle switch (Scan / Hold) and a reset switch (Reset). The sub-unit is composed of a housing, a circuit and a network cable socket, and has no control switch.

[0032] The circuits of the main unit, the sub-unit and each wire core of the cable to be tested are connected in series to form a multi-parallel circuit. The main unit emits pulses to scan each network wire core one by one. If it is conductive, the LED indicator light in the loop flashes, indicating that the wire core is conductive, otherwise it is open. By observing whether the LED of each path flashes, initially judge whether the wire core is conductive. At the same time, by observing the flashing sequence and position correspondence relationship of the LED lights on the main unit and the sub-unit, judge whether the connectors and the wire cores correspond correctly. If the 8-way LED indicator lights are all off, it is necessary to check whether the shielding layer of the cable to be tested is conductive, or check whether there is a fault in this detection device, because the possibility of all 8 wire cores being open is relatively low.

[0033] After the line detection is completed, the stability of the conduction of each wire core and joint can be further detected to check whether there is poor contact. The implementation method is as follows: a small relay is installed in each detection loop. The electromagnetic coil of the relay is connected in series with an LED indicator light. The common contact of the relay is powered on through a changeover switch, and the electromagnetic coil of the relay is connected to the normally open contact of the relay. When the loop is scanned, the relay is attracted and self-maintained, the LED is lit and remains on. When the LED lights of the 8 loops formed by 8 wire cores are all lit and maintained, the host stops scanning. At this time, the maintenance personnel can shake the cable or the host or the auxiliary machine. If during the shaking process, when there is an instantaneous open circuit or poor contact in a certain loop, the self-maintenance of the corresponding relay fails, the contact is disconnected, and the corresponding LED light goes out, indicating that there is a problem with the wire core corresponding to this LED indicator light. If all 8 LED indicator lights remain lit during the shaking process, it means that this cable is of reliable quality and has no defects. The conduction quality and stability of the communication cable are detected in this way.

[0034] Appendix Figure 1 The technical schematic diagram of this embodiment is shown as follows. Among them, 1 is the main circuit and joint of this device, 2 is the communication network line to be detected, and 3 is the auxiliary circuit and joint of this device;

[0035] As shown in the appendix Figure 2 , the main circuit includes a power supply, a switch, a relay, an NE555 pulse generator, a 4017 decimal counting chip, resistors, capacitors, and a shielded RJ45 socket.

[0036] The pulse generator composed of NE555 and resistors and capacitors generates pulses of about 2 Hz (which can be adjusted by a variable resistor) to trigger the clock terminal (CLK) of the 4017 chip, so that the outputs of the 4017 from Y0 to Y9 output high levels in sequence. For example, when the first pulse arrives, the output terminal Y0 is at a high level and the others are at low levels; when the second pulse arrives, the output terminal Y1 is at a high level and the rest are at low levels; when the third pulse arrives, the output terminal Y2 is at a high level and the others are at low levels; and so on. After the high level of the 10th output terminal Y9 ends, it returns to Y0 to output a high level, and as long as the pulses continue, it loops continuously. The principle of this part is not the content of the present invention, so it will not be described in detail.

[0037] K1, K2,..., K8 in the main circuit are 8 relays (due to space limitations, K3 - K7 and the corresponding loops in the figure are omitted), which are respectively connected in series with 8 LED (L1 - L8) indicator lights. Each LED light is connected in parallel with a resistor (R1 - R8 respectively). The ends of these 8 circuits are respectively connected to 8 pins of the RJ45 socket. The negative pole of the power supply is the common terminal, which is connected to the shielding layer of the RJ45 socket, as Figure 1 G;

[0038] The secondary circuit also includes 8 LED lights of the same specification and resistors connected in parallel respectively (the circuits where L13 - L17 are located in the figure are omitted due to space limitations). These 8 lines are respectively connected to 8 pins of the RJ45 socket. The shielding layer is the common terminal.

[0039] The function of the resistor connected in parallel with the LED light is to shunt. Because the operating current of the relay electromagnetic coil is usually dozens of milliamperes, while the operating current of the LED indicator light is only a few milliamperes. Without a shunt resistor, there will be an embarrassing situation where the LED indicator light is lit but the relay cannot be attracted. Therefore, in order for the LED indicator lights and the relay connected in series to work properly at the same time, each LED indicator light needs to be connected in parallel with a shunt resistor. The size of the shunt resistor depends on the resistance value of the relay electromagnetic coil. The power supply is selected as 7 - 9V, and a relay with a coil operating voltage of 2 - 3V is selected. The resistance value after the shunt resistor and the LED light are connected in parallel should be equivalent to the resistance value of the relay electromagnetic coil. In this way, the three series components of the relay, the main - machine LED lights, and the secondary - machine LED indicator lights basically share the output voltage of the 4017 chip equally, and the output voltage of the 4017 is close to the power - supply voltage. Therefore, the voltage shared by each LED light is equivalent to one - third of the power - supply voltage, about 2.33 - 3V, and the LED lights can be normally lit. If the measured communication network cable is relatively long, for example, hundreds of meters or longer, the internal resistance of the detected wire core cannot be ignored. The resistance of about 10 ohms of the detected wire core needs to be added to the series circuit, and the coil resistance of the small relay is about 50 ohms. Calculated, the voltage division of the relay and the LED is not less than 2V. This voltage can also normally light the LED indicator light.

[0040] When K (corresponding to Figure 1 switch On) is closed, K0 (corresponding to Figure 1When the switch Scan is disconnected, the power indicator L lights up, NE555 starts to output pulses, and the 4017 counting module outputs high levels from the output terminals Y0 to Y9 in sequence. When Y0 outputs a high level, the loop formed by the series connection of the K1 relay electromagnetic coil, the R1 and L1 of the host, the first core of the tested network cable, the R11 and L11 of the auxiliary machine, and the shielded wire of the tested network cable is turned on, generating current. The indicator lights L1 on the host and L11 on the auxiliary machine are lit at the same time, indicating that the first core and connector of the tested network cable are turned on. If they are not lit, it means that the core or connector corresponding to this loop is blocked. After the high level output of Y0 ends, L1 and L11 go out, and it is Y1's turn to output a high level. L2 and L12 of this loop light up, indicating that the second core and connector of the tested line are normal, otherwise it is faulty. Similarly, when Y7 outputs a high level, the 8th core is scanned. So far, all 8 cores of the tested network cable have been scanned once. In this process, by observing whether the 8-way indicator lights on the main and auxiliary units are on, it can be determined whether each wire core of the detected line is conductive and whether the correspondence between each connector pin and wire core is correct.

[0041] After completing the alignment test, close K0 (corresponding to Figure 1 Switch Hold) can further detect the stability of the conduction of each core and connector. At this time, the common contacts of K1~K8 are connected through K0, K and the positive pole of the power supply. When Y0~Y7 of the 4017 chip output high level in sequence, if the core of the detected line is turned on, the relays K1~K8 will be attracted in sequence, and once attracted, self-protection occurs. That is, self-holding, the relay will not be disconnected due to the disappearance of the high power output of Y0~Y7, because the electromagnetic coil of the relay is connected to the normally open contact, and the electromagnetic coil obtains a stable power supply after the relay is attracted, so the circuit is always kept in the on state, that is, each LED light on the host and the slave is always on. If a core or connector has poor contact, when the electromagnetic coil of the relay connected in series in this circuit loses power instantly, the contact is disconnected, the self-protection fails, and the LED indicator connected in series with it goes out. By observing whether the LED indicator of each circuit is always on, the reliability and stability of each core and connector of the detected communication network line can be judged. (It should be noted here that in the self-protection state, the Y0~Y7 terminals are connected to the positive pole of the power supply through the normally open contacts K1~K8, so they are always at a high level. Since 4017 has the characteristic of unidirectional output, these high levels from the positive pole of the power supply will not damage the internal circuit of the 4017 chip.)

[0042] Moreover, during the detection process, when each circuit is in the self-holding state, the inspector can further capture and determine the location of poor contact of the communication cable by shaking different parts or joints of the cable to be detected. For example, if self-holding fails when a certain part or a joint of the cable is shaken, it is very likely that this is where the cable fault lies. After repeated operations for many times, the location can be further accurately determined. This function is very practical for on-site troubleshooting of hidden faults.

[0043] When the Y8 output of 4017 is at a high level, K9 is energized, and the normally closed contact of K9 is disconnected, cutting off the pulse from NE555 to the CLK terminal of the 4017 chip. The 4017 chip immediately stops scanning, Y8 will remain at a high level all the time, and K9 will remain energized. The function of this is that when K1 - K8 are in self-holding state, it is not necessary for Y0 - Y7 to output a high level anymore. If a high level is output again, it will interfere with the judgment of the self-holding state, that is, interfere with the judgment of the conduction stability of the wire core. If re-scanning is needed, just press the K10 button. K10 is a normally closed switch, corresponding to Figure 2 the Reset. At this time, K9 is disconnected, and its normally closed contact makes the pulse terminal of NE555 and the CLK terminal of 4017 resume conduction. 4017 continues to scan cyclically, the high level of Y8 ends, and then high levels are output successively at Y9, Y0, Y1, Y2, ……, Y7 until Y8 outputs a high level again, and scanning stops due to K9 being energized. That is, every time the Reset switch is pressed, the host scans one cycle. The function of R10 is voltage division. By selecting an appropriate resistance value of R10, the working voltage matching the coil of K9 can be obtained. The communication line detection device in this embodiment includes a host and a slave. The host and the slave are respectively plugged into both ends of the communication cable to be detected. The internal circuits of the host and the slave and each wire core of the cable under test are connected in series to form a multi-path parallel circuit. The host sends out pulse signals to scan and detect each wire core of the communication cable one by one. If the scanned wire core and joint are conducting, the indicator lights respectively set on the host and the slave and in series with them will flash once, indicating that the wire core and joint are conducting, so as to judge the conduction and disconnection of each wire core and the corresponding situation between the cable joint and the wire core. In addition to the scanning detection function, this device also includes a holding detection function. After switching to the holding detection function, the relay self-holding circuits of each loop are put into operation. The host sends out pulse signals, and the corresponding relays are energized and self-held, and the indicator lights are always on. Once there is poor contact in the wire core or joint, the relay self-holding ends and the indicator light goes out. Based on this, the reliability of each wire core and joint can be judged.

Claims

1. A communication cable detection device, comprising an active detection end device and a passive detection end device, wherein the active detection end device and the passive detection end device are sequentially connected using a communication cable to be tested, and the active detection end device sequentially sends a detection signal to the passive detection end through each core wire of the communication cable to be tested; The active detection end device comprises: a signal generator generating a detection signal, sending the detection signal to a signal transmitter generating each core wire of the communication cable to be tested; The passive end detection device comprises: a signal receiving device for receiving detection signals through each core wire of the communication cable to be tested, and an indicating device for indicating the state of the signal received from each core wire of the communication cable to be tested; The feature is that the signal transmitter of the active detection end device also includes a self-protection device that continues to send the detection signal after the signal generator stops working.

2. The communication cable detection device according to claim 1, characterized in that: The communication cable to be tested is a cable having 8 core wires and an external shielding layer G, and having cable connectors (2) at both ends; the cable connector is an RJ45 plug; The signal transmitter comprises a transmitting end (1), wherein the transmitting end (1) is an RJ45 socket, and the shielding layer G of the 8-core cable is connected to the negative pole of the active detection device; The signal receiving device comprises a receiving end (3), which is an RJ45 socket; the indicating device is an LED indicator light L11-L18 connected to each core wire of the RJ45 plug and the shielding layer G.

3. The communication cable detection device according to claim 2, characterized in that: The signal generator comprises a pulse generator and a decimal counter, wherein the pulse output end of the pulse generator is connected to the CLK end of the decimal counter, and the Y0-Y7 of the output end of the pulse generator are respectively connected to the 1-8 pins of the RJ45 socket of the transmitting end (1).

4. The communication cable detection device according to claim 3, characterized in that: The chip model used by the decimal counter is a 4017 chip.

5. The communication cable detection device according to claim 4, characterized in that: The chip model used by the pulse generator is NE555.

6. The communication cable detection device according to claim 5, characterized in that: The self-protection device includes relays K1-K8 respectively arranged on the connecting line connecting Y0-Y7 of the output end of the pulse generator and 1-8 pins of the RJ45 socket; one end of the electromagnetic coil of the relay K1-K8 is respectively connected to Y0-Y7 of the output end of the pulse generator, and the other end is respectively connected in series with the LED indicator light and then connected to 1-8 pins of the RJ45 socket; the common end of the relay K1-K8 is connected to the positive pole of the power supply through K0 and K1, and the normally open contacts are respectively connected to Y0-Y7 of the output end of the pulse generator.

7. The communication cable detection device according to claim 6, characterized in that: LED indicator lights L1-L8 are also connected in series between Y0-Y7 at the output end of the pulse generator and pins 1-8 of the RJ45 socket.

8. The communication cable detection device according to claim 7, characterized in that: It also includes shunt resistors R1-R8 and R11-R18; the shunt resistors R1-R8 are respectively connected in parallel to the two ends of the LED indicator lights L1-L8, and the shunt resistors R11-R18 are respectively connected in parallel to the two ends of the LED indicator lights L11-L18.

9. The communication cable detection device according to claim 7, characterized in that: The resistance value of the shunt resistor and the LED lamp in parallel is comparable to the resistance value of the relay electromagnetic coil.

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