A remote monitoring system and its Internet of Things electromagnetic relay

Abstract

A remote monitoring system and an Internet of Things electromagnetic relay thereof, comprising a housing and an electromagnetic relay body, an NB‑IOT communication module and a sensor arranged in the housing, wherein the NB‑IOT communication module is used to establish a connection with a cloud server, and the NB‑IOT communication module comprises a signal acquisition circuit, a microcontroller and a NB‑IOT chip. When the electromagnetic relay body is powered, the signal acquisition circuit acquires the state information of the electromagnetic relay body through the sensor, and the microcontroller collects and processes the state information of the electromagnetic relay body acquired by the signal acquisition circuit, and sends it to the cloud server through the NB‑IOT chip, and the cloud server classifies, stores and analyzes the information uploaded by the NB‑IOT communication module. A remote control system and an Internet of Things electromagnetic relay thereof of the present invention establish a connection with a cloud server through an NB‑IOT communication module, and the cloud server classifies, stores and analyzes the information, thereby realizing cloud communication of the electromagnetic relay and meeting the needs of intelligent use.

Description

Technical Field

[0001] The invention relates to a switch device, and in particular to a remote monitoring system and an Internet of Things electromagnetic relay thereof. Background Art

[0002] Electromagnetic relay is an electronic control device used in automatic control circuits. It has an electromagnetic system (also called input circuit) and a contact system (also called output circuit). Its working principle is to use a smaller current and a lower voltage to control a larger current and a higher voltage. It is an automatic switch. Existing relays collect voltage, current, temperature and other signals through a communication circuit unit and transmit them to a field or remote signal processing system. However, the signal transmission is achieved by using an output signal interface to connect an external human-machine device, or using a mobile communication terminal (such as a mobile phone, PDA, smart phone, etc.), a display device, etc. connected by a wireless communication device, so that the transmitted relay signal data can only be collected by the staff on site or through the network, and cloud communication cannot be realized, which is not conducive to intelligent applications. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a remote monitoring system capable of realizing cloud communication and an Internet of Things electromagnetic relay thereof.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] An Internet of Things electromagnetic relay comprises a shell, an electromagnetic relay body, an NB-IOT communication module and a sensor arranged in the shell, wherein the NB-IOT communication module is used to establish a connection with a cloud server, and the NB-IOT communication module comprises a signal acquisition circuit, a microcontroller and an NB-IOT chip. When the electromagnetic relay body is powered, the signal acquisition circuit acquires state information of the electromagnetic relay body through the sensor, and the microcontroller collects and processes the state information of the electromagnetic relay body acquired by the signal acquisition circuit, and sends the state information to the cloud server through the NB-IOT chip.

[0006] Preferably, the electromagnetic relay body includes a contact group and a coil for controlling the power supply of the electromagnetic relay body, the signal acquisition circuit includes a current sampling circuit and a voltage sampling circuit, and the status information of the electromagnetic relay body collected by the signal acquisition circuit through the sensor includes the contact group current signal and the number of power-on times, the coil voltage signal and the number of power-on times, wherein the current sampling circuit is used to collect the contact group current signal and the number of power-on times, and the voltage sampling circuit is used to collect the coil voltage signal and the number of power-on times.

[0007] Preferably, the sensor includes at least one current sensor, and the current sensor is used to collect current signals of the contact group of the electromagnetic relay body. The current sensor transmits the current signal of the contact group to the signal acquisition circuit and the microcontroller performs signal processing.

[0008] Preferably, each time the contact group of the electromagnetic relay body is energized, the current sensor transmits the detected current signal to the signal acquisition circuit and the microcontroller processes the signal. After processing by the microcontroller, the NB-IOT communication module uploads a signal as the number of times the contact group is energized to the cloud server. The cloud server accumulates and counts the signal of the number of times the contact group is energized to calculate the electrical life.

[0009] Preferably, the current sensor is a sampling resistor connected to the signal acquisition circuit, the sampling resistor is a manganese copper sampling resistor, one end of the sampling resistor is connected to the lead pin of the electromagnetic relay body, and the other end of the sampling resistor is connected to the contact group of the electromagnetic relay body, and two signal acquisition terminals are provided on both sides of the sampling resistor for connecting to a microcontroller.

[0010] Preferably, the lead pin of the electromagnetic relay body is an electrical connecting sheet, a second electrical connecting sheet is provided at the other end of the sampling resistor, the manganese copper sampling resistor is in sheet shape and the thickness of the manganese copper sampling resistor is the same as the thickness of the electrical connecting sheet and the second electrical connecting sheet, the sampling resistor and the electrical connecting sheet and the second electrical connecting sheet form a whole, a first signal acquisition end is provided at the upper end of one side of the sampling resistor perpendicular to the protrusion of the sampling resistor, and an L-shaped second signal acquisition end is provided at the lower end of the other side of the sampling resistor, the L-shaped second signal acquisition end includes a vertical segment and a horizontal segment connected in an L shape, the vertical segment is parallel to the other side of the sampling resistor and is connected to the lower end of the other side of the sampling resistor, and the horizontal segment is parallel to the first signal acquisition end.

[0011] Preferably, an installation cavity and a protective cover for sealing the installation cavity are provided in the shell, a PCB board is installed in the installation cavity, a sensor and a NB-IOT communication module are integrated on the PCB board, the PCB board and the electromagnetic relay body are separated and arranged in the shell by the protective cover, and the lead pins of the electromagnetic relay body are connected to the PCB board.

[0012] Preferably, the PCB board is connected to the coil to collect the voltage signal at both ends of the coil. Each time the coil of the electromagnetic relay body is energized, a signal as the number of times the coil is energized is uploaded to the cloud server by the NB-IOT communication module after being processed by the microcontroller. The cloud server counts the signal of the number of times the coil is energized and accumulates the count to calculate the mechanical life.

[0013] Preferably, the sensor also includes one or more of a temperature sensor, a humidity sensor, a gas smoke sensor, and a vibration sensor; the temperature sensor is a temperature sensor for collecting the temperature inside the shell, the gas smoke sensor is used to sense whether there is some or certain smoke in the environment, the humidity sensor is used to sense the ambient humidity, and the vibration sensor is used to sense whether there is abnormal vibration in the application environment. The temperature sensor, humidity sensor, gas smoke sensor, and vibration sensor transmit the collected signals to the microcontroller for processing, and after processing by the microcontroller, the NB-IOT communication module uploads them to the cloud server.

[0014] Preferably, the NB-IOT communication module also includes a power supply circuit, the input end of the power supply circuit is connected to the coil of the electromagnetic relay body, and the output end of the power supply circuit is connected to the signal acquisition circuit, the NB-IOT chip, and the control circuit of the microcontroller. When the coil is energized, the power supply circuit supplies power to the signal acquisition circuit, the NB-IOT chip, and the microcontroller, and the NB-IOT communication module establishes a connection with the cloud server.

[0015] A remote monitoring system includes a cloud server for receiving status information uploaded by an Internet of Things electromagnetic relay as described above, wherein the Internet of Things electromagnetic relay is connected in a load circuit for controlling the power supply of the load device, and the cloud server can send a control signal to the Internet of Things electromagnetic relay to turn on or off the load circuit, and when the cloud server monitors that the status information uploaded by the Internet of Things electromagnetic relay exceeds a preset threshold or reaches an alarm value, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay.

[0016] A remote monitoring system includes a cloud server for receiving status information uploaded by an Internet of Things electromagnetic relay as described above. The cloud server groups a plurality of Internet of Things electromagnetic relays connected to the network, and sets a current threshold and a temperature threshold for each group of Internet of Things electromagnetic relays. When it is monitored that the current information uploaded by a certain Internet of Things electromagnetic relay is greater than the current threshold of the corresponding group, or is less than the current threshold of the corresponding group, or when it is monitored that the temperature information uploaded by a certain Internet of Things electromagnetic relay is greater than the temperature threshold of the corresponding group, or is less than the temperature threshold of the corresponding group, an early warning message is issued and / or the Internet of Things electromagnetic relay is disconnected.

[0017] Furthermore, the cloud server groups multiple networked IoT electromagnetic relays, analyzes the collected current and temperature data of the IoT electromagnetic relays in the same group and makes a mathematical model. When it is monitored that the temperature and current information of the IoT electromagnetic relays in the group obviously exceeds the corresponding threshold of the mathematical model, an early warning message is issued and / or the IoT electromagnetic relays are disconnected.

[0018] Furthermore, the cloud server makes a mathematical model of the fitting curve based on the collected status information, and fits the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration information as variables to obtain a fitting curve, and obtains a maximum threshold curve and / or a minimum threshold curve by moving the fitting curve at a certain proportion, such as shifting upward to obtain the maximum threshold curve and shifting downward to obtain the minimum threshold curve. When the cloud server monitors that the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration variables of a certain IoT electromagnetic relay in the group are outside the maximum threshold curve and the minimum threshold curve, a warning message is issued and / or the IoT electromagnetic relay is disconnected.

[0019] Furthermore, the cloud server groups the multiple networked IoT electromagnetic relays, and the cloud server obtains variable thresholds by fitting the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration information according to the set mathematical model used for the group and the set mathematical model. When it is monitored that the fitting variables of the IoT electromagnetic relays of the group obviously exceed the corresponding variable thresholds of the mathematical model, an early warning message is issued and / or the IoT electromagnetic relays are disconnected.

[0020] Furthermore, the cloud server records the original state parameters of the Internet of Things electromagnetic relay and the original parameters of the load device connected to the load circuit, and the cloud server calculates the electrical life of the Internet of Things electromagnetic relay and / or the load device through the state information uploaded by the Internet of Things electromagnetic relay.

[0021] Furthermore, the load circuit is a sewage valve circuit, and the status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, and the current signal is used to feedback the opening and closing status of the Internet of Things electromagnetic relay and the opening and closing status of the sewage valve circuit; and or, the cloud server records the number of times the sewage valve circuit is opened based on the acquired current signal, which is used to calculate the life of the sewage valve.

[0022] Furthermore, the status information uploaded by the IoT electromagnetic relay to the cloud server includes humidity signals and gas smoke concentration signals, which are used to detect whether there is a leak in the sewage valve near the IoT electromagnetic relay. When the cloud server determines that there is an abnormality based on the humidity signal and gas smoke concentration signal, it will issue an alarm or directly shut down the IoT electromagnetic relay.

[0023] Furthermore, the load circuit is a petroleum equipment circuit, and the status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal and a temperature signal. The current signal is used to feedback the on and off status of the Internet of Things electromagnetic relay and the on and off status of the petroleum equipment circuit, and the temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the oil well equipment.

[0024] Furthermore, the load circuit in the remote monitoring system is a mining equipment circuit, and the status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, a temperature signal, a vibration frequency signal and a gas smoke concentration signal. The current signal is used to feedback the on and off status of the Internet of Things electromagnetic relay and the on and off status of the mining equipment circuit. The temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the mining equipment. The vibration frequency is used to reflect whether abnormal vibration occurs in the working environment of the Internet of Things electromagnetic relay and the mining equipment. The gas smoke concentration signal is used to reflect whether there is abnormal gas in the working environment of the Internet of Things electromagnetic relay and the mining equipment.

[0025] An Internet of Things electromagnetic relay of the present invention transmits status information of an electromagnetic relay body collected by a sensor to an NB-IOT communication module. The NB-IOT communication module processes the status information and then transmits it to a cloud server, which performs classification, storage, and analysis processing. With the cooperation of the electromagnetic relay body, the sensor, and the NB-IOT communication module, a connection is established with the cloud server, so that the electromagnetic relay realizes cloud communication and meets the needs of intelligent use.

[0026] In addition, the current signal of the contact group, the number of times the contact group is energized, the voltage signal of the coil, and the number of times the coil is energized are collected through the signal acquisition circuit, and the signal is transmitted to the cloud server through the NB-IOT communication module. The cloud server accumulates the counts to obtain the electrical life and mechanical life of the electromagnetic relay respectively.

[0027] In addition, the sensor also includes a temperature sensor, which transmits the collected temperature signal of the electromagnetic relay body to the cloud server; it can also include a sensor for obtaining working environment status information, which is used to transmit the working environment of the Internet of Things electromagnetic relay to the cloud server.

[0028] In addition, the sensor and the NB-IOT communication module are integrated on a PCB board, and a mounting cavity for mounting the PCB board is provided in the housing. The PCB board is separated from the electromagnetic relay body by a protective cover, thereby providing dust protection for the PCB board.

[0029] A remote monitoring system of the present invention is based on signal transmission among an Internet of Things electromagnetic relay, a cloud server and an operation platform, so that the Internet of Things electromagnetic relay controls a load circuit under the control of the cloud server to realize remote control. At the same time, the Internet of Things electromagnetic relay uploads status information to the cloud server, so that the operation platform can obtain the working status of the Internet of Things electromagnetic relay and the load circuit in time, thereby realizing remote monitoring. The system is particularly suitable for monitoring polluting fields such as chemical industry and light industry, as well as workplaces such as furnaces and oil wells that are not convenient for real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1-2 It is a schematic diagram of an Internet of Things electromagnetic relay of the present invention;

[0031] Figure 3 It is a structural schematic diagram of an Internet of Things electromagnetic relay of the present invention;

[0032] Figure 4 It is a cross-sectional view of an Internet of Things electromagnetic relay of the present invention;

[0033] Figure 5 It is a structural schematic diagram of an electromagnetic relay body in an Internet of Things electromagnetic relay of the present invention;

[0034] Figure 6 It is a schematic diagram of lead pins and sampling resistors in an Internet of Things electromagnetic relay of the present invention;

[0035] Figure 7 It is a schematic diagram of a remote control system of the present invention. DETAILED DESCRIPTION

[0036] The following is combined with Figures 1 to 7 The given embodiments further illustrate the specific implementation of a remote monitoring system and an Internet of Things electromagnetic relay of the present invention. A remote monitoring system and an Internet of Things electromagnetic relay of the present invention are not limited to the description of the following embodiments.

[0037] An Internet of Things electromagnetic relay comprises a housing 1, an electromagnetic relay body 2, an NB-IOT communication module and a sensor arranged in the housing 1, wherein the NB-IOT communication module is used to establish a connection with a cloud server, and the NB-IOT communication module comprises a signal acquisition circuit, a microcontroller and a NB-IOT chip. When the electromagnetic relay body 2 is powered, the signal acquisition circuit acquires state information of the electromagnetic relay body 2 through the sensor, the microcontroller collects and processes the state information of the electromagnetic relay body 2 acquired by the signal acquisition circuit, and sends the state information to the cloud server through the NB-IOT chip, and the cloud server classifies, stores and analyzes the information uploaded by the NB-IOT communication module.

[0038] An Internet of Things electromagnetic relay of the present invention transmits the status information of the electromagnetic relay body 2 collected by the sensor to the NB-IOT communication module. The NB-IOT communication module processes the status information and transmits it to the cloud server. The cloud server classifies, stores and analyzes the status information. With the cooperation of the electromagnetic relay body 2, the sensor and the NB-IOT communication module, a connection is established with the cloud server, so that the electromagnetic relay can realize cloud communication and meet the needs of intelligent use.

[0039] Combination Figure 1-6An embodiment of an Internet of Things electromagnetic relay is provided, an Internet of Things electromagnetic relay, comprising a housing 1 and an electromagnetic relay body 2, an NB-IOT communication module and a sensor arranged in the housing 1, the electromagnetic relay body 2 comprising a contact group 22 and a coil for controlling the electromagnetic relay body 2 to be energized, when the coil of the electromagnetic relay body 2 is energized and attracted, the contact group 22 is closed as the coil is energized, the NB-IOT communication module is used to establish a connection with a cloud server, the NB-IOT communication module comprises a signal acquisition circuit, a microcontroller and a NB-IOT chip, when the electromagnetic relay body 2 is energized, the signal acquisition circuit collects the electromagnetic relay body through the sensor 2, the microcontroller collects and processes the status information of the electromagnetic relay body 2 collected by the signal acquisition circuit, and sends it to the cloud server through the NB-IOT chip. The cloud server classifies, stores, analyzes and processes the information uploaded by the NB-IOT communication module. Preferably, the signal acquisition circuit also includes a power circuit, the input end of the power circuit is connected to the coil of the electromagnetic relay body 2, and the output end of the power circuit is connected to the signal acquisition circuit, the NB-IOT chip, and the control circuit of the microcontroller. When the coil is energized, the power circuit supplies power to the signal acquisition circuit, the NB-IOT chip, and the microcontroller, and the NB-IOT communication module establishes a connection with the cloud server.

[0040] The signal acquisition circuit for collecting the status information of the electromagnetic relay body 2 includes a current sampling circuit and a voltage sampling circuit. The status signal of the electromagnetic relay body 2 includes the current signal of the contact group 22, the number of times the contact group 22 is energized, the coil voltage signal, and the number of times the coil is energized. The current signal of the contact group 22 and the number of times the contact group 22 is energized are collected by the current sampling circuit through a sensor, and the coil voltage signal and the number of times the coil is energized are collected by the voltage sampling circuit through a sensor.

[0041] The sensor includes a current sensor, which is used to collect the current signal and the number of power-on times of the contact group 22. The number of current sensors is at least one, and the number of current sensors is equal to the number of contact groups 22 of the electromagnetic relay body 2. Each time the contact group 22 of the electromagnetic relay body 2 is powered, the current sensor transmits the detected current signal to the signal acquisition circuit and the microcontroller performs signal processing. After being processed by the microcontroller, the NB-IOT communication module uploads a signal as the number of times the contact group 22 is powered to the cloud server. The cloud server accumulates and counts the signal of the number of times the contact group 22 is powered, which is used to calculate the number of electrical life of the electromagnetic relay.

[0042] In this embodiment, the current sensor is a sampling resistor 4 connected to the signal acquisition circuit, the sampling resistor 4 is a manganese copper sampling resistor, one end of the sampling resistor 4 is connected to the lead pin 21 of the electromagnetic relay body 2, and the other end is connected to the contact group 22 of the electromagnetic relay body 2, and two signal acquisition terminals 41 are provided on both sides of the sampling resistor 4 for connecting to the microcontroller. Preferably, the lead pin 21 of the electromagnetic relay body 2 is an electrical connection sheet, the sampling resistor 4 is a sheet-shaped manganese copper sampling resistor 4, a second electrical connection sheet is provided at the other end of the sampling resistor 4, and the second electrical connection sheet realizes the connection of the contact group 22 with the sampling resistor 4 through the connecting wire 23, and the two signal collection terminals 41 on both sides of the sampling resistor 4 are respectively the first signal collection terminal and the second signal collection terminal, and the first signal collection terminal is provided at the upper end of one side of the sampling resistor 4 perpendicular to the protrusion of the sampling resistor 4, and the L-shaped second signal collection terminal is provided at the lower end of the other side of the sampling resistor 4, and the L-shaped second signal collection terminal includes a vertical section and a horizontal section connected in an L shape, the vertical section is parallel to the other side of the sampling resistor 4, and is connected to the lower end of the other side of the sampling resistor 4, and the horizontal section is parallel to the first signal collection terminal. The thickness of the sampling resistor 4 is the same as the thickness of the electrical connection sheet and the second electrical connection sheet, and such a structure enables the sampling resistor 4 to be connected as a whole with the electrical connection sheet and the second electrical connection sheet. See FIG. Figure 6 ,like Figure 3-6 As shown, the second electrical connection sheet can connect the contact group 22 to the sampling resistor 4 through the connecting wire 23.

[0043] In this embodiment, it is preferred that Figure 3 , 4 As shown, the sensor and the NB-IOT communication module are integrated on a PCB board 3. The NB-IOT chip in the NB-IOT communication module is MT2625. The MT2625 chip is a NB-IOT universal module with ultra-high integration. A microcontroller (MCU), pseudo-static random access memory (PSRAM), flash memory and a power management unit (PMU) are integrated on the same chip.

[0044] An installation cavity 11 for installing the PCB board 3 is provided in the housing 1. Preferably, the installation cavity 11 is opposite to the contact arc extinguishing cavity (not shown) of the electromagnetic relay body 2. The installation cavity 11 is provided with a protective cover 12 for dust prevention. The protective cover 12 separates the PCB board 3 from the electromagnetic relay body 2 and is arranged in the housing 1. The lead pins 21 of the electromagnetic relay body 2 are connected to the PCB board 3. Figure 4 As shown, the lead pin 21 at one end of the PCB board 3 is connected, and the pin wire of the coil is welded on the PCB board 3, so that the PCB board 3 samples the voltage at both ends of the coil; the sampling resistor 4 is used to collect the current signal, and the signal collection end 41 of the sampling resistor 4 is installed on the PCB board 3 and connected by soldering.

[0045] Specifically, the PCB board 3 is connected to the coil in the electromagnetic relay body 2 and is used to collect the voltage signal at both ends of the coil. Each time the coil of the electromagnetic relay body 2 is energized, a signal as the number of times the coil is energized is uploaded to the cloud server by the NB-IOT communication module after being processed by the microcontroller. The number of times the coil is energized also represents the number of times the electromagnetic relay body 2 is attracted. The cloud server accumulates and counts the signal of the number of times the coil is energized, which can be used to calculate the mechanical life of the electromagnetic relay.

[0046] Preferably, the sensor also includes a temperature sensor for collecting the temperature inside the housing 1, and the temperature sensor transmits the collected temperature signal to the microcontroller for processing, and the NB-IOT communication module uploads the collected temperature signal to the cloud server after processing by the microcontroller. Of course, the sensor is not limited to current sensors and temperature sensors. According to the application environment of the Internet of Things electromagnetic relay, sensors with other functions can also be set, such as sensors for sensing environmental humidity, vibration sensors for sensing whether there are abnormal vibrations in the application environment, and gas smoke sensors for sensing whether there are certain or certain types of smoke in the working environment.

[0047] The Internet of Things electromagnetic relay of the present application, the power supply circuit, the signal acquisition circuit, the microcontroller (MCU) and the NB-IoT communication chip are welded on a PCB board 3; the PCB board 3 and the sensor are installed in the electromagnetic relay housing. Compared with the equipment of the existing electromagnetic relay, the Internet of Things electromagnetic relay of the present application can sense the operation of the Internet of Things electromagnetic relay and its load circuit in a dangerous environment, and the safety information of its surrounding environment (such as the humidity, vibration and presence of dangerous gas or smoke in the application environment), and upload it to the cloud server through the Internet of Things. The cloud server performs big data analysis on the current data of multiple Internet of Things electromagnetic relays with the same purpose collected, and of course, it can also perform big data analysis on the surrounding environment data such as humidity, vibration and gas collected at the same time, and make a mathematical model of the current and surrounding environment information under normal conditions. When the relay parameter value is monitored to be obviously beyond the limit of the mathematical model, or there is a situation close to the preset relay abnormal alarm value, a warning message is issued or fault protection is directly performed. Therefore, the system can achieve real-time perception and make accurate identification and quick response.

[0048] like Figure 7As shown, based on the remote control function of the above-mentioned Internet of Things electromagnetic relay, a remote monitoring system is established, including a cloud server, an Internet of Things electromagnetic relay and a load circuit controlled by the Internet of Things electromagnetic relay, a local control device controls the load circuit through the corresponding Internet of Things electromagnetic relay, multiple Internet of Things electromagnetic relays are connected to the cloud server, the cloud server is used to receive the state information uploaded by the Internet of Things electromagnetic relay, the Internet of Things electromagnetic relay is connected in the load circuit for controlling the power supply of the load device, the state information includes current information, preferably also includes temperature information, humidity information, gas smoke information and vibration information and other state information about the working environment, the cloud server can send a control signal to the Internet of Things electromagnetic relay to turn on or off the load circuit. When the cloud server monitors that the state information exceeds the threshold, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay. For example, when the current information uploaded by the Internet of Things electromagnetic relay is greater than the current threshold, or less than the current threshold, or when the cloud server monitors that the temperature information uploaded by the Internet of Things electromagnetic relay is greater than the temperature threshold, or less than the temperature threshold, the cloud server issues a warning message and / or disconnects the Internet of Things electromagnetic relay.

[0049] As a preferred embodiment, the cloud server has an Internet of Things electromagnetic relay grouping function, which groups multiple Internet of Things electromagnetic relays connected to the network and performs different monitoring and protection configurations; users can group according to the use environment of the Internet of Things electromagnetic relay, the equipment of the load circuit controlled by it, and other conditions, and set the current threshold and temperature threshold of each group of Internet of Things electromagnetic relays. When an early warning message is issued to monitor that the current information uploaded by a certain Internet of Things electromagnetic relay is greater than the current threshold of the corresponding group, or less than the current threshold of the corresponding group, or the temperature information uploaded by a certain Internet of Things electromagnetic relay is greater than the temperature threshold of the corresponding group, or less than the temperature threshold of the corresponding group, an early warning message is issued and / or the Internet of Things electromagnetic relay is disconnected. It should be noted that the current threshold and temperature threshold here do not refer to the rated current or overload current of the Internet of Things electromagnetic relay or the applicable temperature threshold of the Internet of Things electromagnetic relay. The protection of the rated current or overload current or the applicable temperature threshold is generally self-protected by the MCU circuit of the Internet of Things electromagnetic relay; the current threshold and temperature threshold here refer to the monitoring of the load circuit controlled by the Internet of Things electromagnetic relay. The cloud server protects the load circuit based on the information uploaded by the Internet of Things electromagnetic relay, and the current signal uploaded by the Internet of Things electromagnetic relay to the cloud server also reflects the power consumption of the load equipment. For example, the Internet of Things electromagnetic relay uploads a temperature signal to the cloud server. The Internet of Things electromagnetic relay is set close to the load device connected to the load circuit. The temperature signal of the Internet of Things electromagnetic relay can simultaneously reflect the temperature of the Internet of Things electromagnetic relay, the load device and its working environment. Of course, when the Internet of Things electromagnetic relay has the function of detecting the surrounding working environment, it is necessary to add relevant thresholds such as humidity, gas density, smoke concentration and vibration frequency. When any item in the Internet of Things electromagnetic relay is higher or lower than the threshold, a warning message is issued and the Internet of Things electromagnetic relay is disconnected.

[0050] As a more preferred embodiment, the cloud server groups multiple Internet of Things electromagnetic relays connected to the network, analyzes the current and temperature data of the Internet of Things electromagnetic relays in the same group, and makes a mathematical model of the temperature and current information in the normal state. When the temperature and current parameter values ​​of the Internet of Things electromagnetic relays in the group are monitored to obviously exceed the corresponding threshold value of the mathematical model, or when there is a situation close to the preset relay abnormal alarm value, a warning message is issued and / or the Internet of Things electromagnetic relay is disconnected. For example, when the working environment and the equipment of the load circuit of 1000 Internet of Things electromagnetic relays monitored at the same time are similar, there is a current or temperature information that is obviously higher or lower than that of other Internet of Things electromagnetic relays, indicating that there may be an abnormality in its working environment or the equipment of the load circuit. Of course, when multiple Internet of Things electromagnetic relays have the function of collecting ambient environment data such as humidity, gas smoke or vibration, the cloud server can also analyze the ambient environment data such as humidity, gas smoke or vibration of the Internet of Things electromagnetic relays in the same group collected and mathematically model the data in the normal state.

[0051] For example, one of the simplest mathematical models is the mean method. Taking the example of the Internet of Things electromagnetic relay only setting the current sensor and the temperature sensor, the cloud server respectively calculates the mean of the current and temperature information of the Internet of Things electromagnetic relays in the same group (which can be the real-time data mean or the mean combined with the long-term use data), obtains the current mean and the temperature mean, and weights the current mean to determine the maximum current threshold and / or the minimum current threshold, and weights the temperature mean to determine the maximum temperature threshold and / or the minimum temperature threshold. For example, the maximum current threshold is 130% of the current mean weighted, and the minimum current threshold is 50% of the current mean weighted. When the cloud server monitors that the current value of a certain Internet of Things electromagnetic relay in the group is greater than the maximum current threshold and / or less than the minimum current threshold, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay. For example, the maximum temperature threshold is 120% of the temperature mean weighted, and the minimum temperature threshold is 60% of the mean weighted. When the cloud server monitors that the temperature value of a certain Internet of Things electromagnetic relay in the group is greater than the maximum temperature threshold and / or less than the minimum temperature threshold, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay.

[0052] As another implementation method of the mathematical model, the cloud server makes a mathematical model of a fitting curve based on the collected status information, and fits the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration information as variables to obtain a fitting curve, and obtains a maximum threshold curve and / or a minimum threshold curve by moving the fitting curve at a certain proportion, such as shifting upward to obtain the maximum threshold curve, and shifting downward to obtain the minimum threshold curve. When the cloud server monitors that the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration variables of a certain IoT electromagnetic relay in the group are outside the maximum threshold curve and the minimum threshold curve, a warning message is issued and / or the IoT electromagnetic relay is disconnected. The fitting method may be the least squares method, Newton interpolation method, or the like.

[0053] Of course, the mathematical model can also be a square difference method, a model based on deep learning, etc.

[0054] As a preferred solution, Figure 7 The cloud server is provided with a software operation platform, and users can perform corresponding monitoring and management through the operation platform, including user management, authority setting, networking and grouping of Internet of Things electromagnetic relays, setting of thresholds, selection of mathematical models (the system has multiple mathematical models preset, and the mathematical models for monitoring can also be customized), selection of state information required by the mathematical model, and one or more of temperature, current, humidity, vibration frequency, and gas smoke concentration information can be selected. The cloud server groups the multiple Internet of Things electromagnetic relays connected to the network, and the cloud server fits the temperature, current, humidity, vibration frequency, and gas smoke concentration information according to the mathematical model used by the group and the mathematical model set to obtain the variable threshold. When the fitting variables of the Internet of Things electromagnetic relays in the group are monitored to obviously exceed the corresponding variable threshold of the mathematical model, the cloud server issues a warning message and disconnects the Internet of Things electromagnetic relays.

[0055] There may be multiple IoT electromagnetic relays and load circuits controlled by the IoT electromagnetic relays. Multiple IoT electromagnetic relays and load circuits are controlled by the same cloud server and operation platform to form a remote centralized control system. When a fault occurs, the user can implement point-to-point or centralized protection of related equipment based on the cloud server.

[0056] The remote monitoring system of the present application can also be used in industrial production safety management systems. The electromagnetic relay uploads the temperature or current information to the cloud server. The cloud server performs big data calculations and processing on the acquired status information. When abnormal trends are found in the parameter data, abnormal information can be discovered early, such as aging of components, poor wiring of lines, and overload and stall of load equipment. The cloud server issues a warning alarm or directly performs fault protection.

[0057] The remote monitoring system of this embodiment enables the Internet of Things electromagnetic relay to control the load circuit under the control of the cloud server to achieve remote control. At the same time, the Internet of Things electromagnetic relay uploads status information to the cloud server, so that the operation platform can obtain the working status of the Internet of Things electromagnetic relay and the load circuit in time, realizing remote monitoring. It is particularly suitable for monitoring polluting fields such as chemical industry and light industry, as well as workplaces such as furnaces and oil wells that are not convenient for real-time monitoring.

[0058] Preferably, the cloud server can also be used to monitor the life of the load device. The cloud server records the original state parameters of the Internet of Things electromagnetic relay and the original parameters of the load device connected to the load circuit. The original parameters of both include a life decay curve. The Internet of Things electromagnetic relay uploads a current signal to the cloud server each time it is turned on and off. The cloud server calculates the electrical life of the Internet of Things electromagnetic relay by counting the number of times the Internet of Things electromagnetic relay uploads the current signal and combining its original state parameters. At the same time, the opening and closing of the Internet of Things electromagnetic relay is related to the opening and closing of the load device connected to the load circuit. When the cloud server obtains the electrical life of the Internet of Things electromagnetic relay based on the number of counted current signals, it can also calculate the electrical life of the load device. For example, the electrical life of the Internet of Things electromagnetic relay is 10,000 times, and the electrical life of the load device is 5,000 times. When the Internet of Things electromagnetic relay is turned on and off for 4,500 times, the cloud server can remind the replacement of the load device. When the Internet of Things electromagnetic relay is turned on and off for 9,000 times, the cloud server can remind the replacement of the Internet of Things electromagnetic relay. That is, the cloud server obtains the status information of the IoT electromagnetic relay connected to it, determines the number of times the relay is turned on and / or closed, and compares it with the obtained rated life threshold of the IoT electromagnetic relay to obtain the electrical life of the IoT electromagnetic relay; and the cloud server also obtains the load electrical life threshold of the load device corresponding to the IoT electromagnetic relay connected to it, determines the number of times the load device is turned on and / or closed based on the status information uploaded by the IoT electromagnetic relay, and compares it with the load electrical life threshold to obtain the electrical life of the load device.

[0059] For example, a remote monitoring system is provided for use in polluting fields such as chemical industry and light industry. The load circuit in the remote monitoring system is a sewage valve circuit. The state information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, and the current signal is used to feedback the opening and closing state of the Internet of Things electromagnetic relay and the opening and closing state of the sewage valve circuit. Compared with the existing sewage control and monitoring system, the present application has the advantages of being more direct and more accurate, and there is no need to modify the sewage valve circuit or sewage motor. For example, when the current signal uploaded by the Internet of Things electromagnetic relay is greater than the sewage valve opening threshold, it means that the sewage valve is open and in the sewage state, otherwise the sewage valve is in the closed state. The cloud server records the number of times the sewage valve circuit is opened based on the acquired current signal, which is used to calculate the life of the sewage valve and remind when it is close to the service life. At the same time, the use of the sewage valve is monitored based on the current signal. When the abnormal current is too large or too small in advance, an alarm prompts or shuts down the Internet of Things electromagnetic relay.

[0060] Furthermore, the sensors integrated on the PCB board also include a humidity sensor and / or a gas smoke sensor. The status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a humidity signal and a gas smoke concentration signal, which is used to detect whether a sewage valve near the Internet of Things electromagnetic relay is leaking. When the cloud server determines that there is an abnormality based on the humidity signal and the gas smoke concentration signal, it issues an alarm or directly shuts down the Internet of Things electromagnetic relay.

[0061] A remote monitoring system is provided for use in the oil well field, wherein the load circuit in the remote monitoring system is a petroleum equipment circuit, and the state information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal and a temperature signal, wherein the current signal is used to feedback the on / off state of the Internet of Things electromagnetic relay and the on / off state of the petroleum equipment circuit, and the temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the oil well equipment, and is suitable for an application environment where the oil equipment is dispersedly arranged. The user sets up through the operation platform, groups the Internet of Things electromagnetic relays connected to the cloud server for controlling the oil well equipment, sets up a mathematical model for fitting the collected current and temperature information using the Newton interpolation method for monitoring (which may include previously stored data of the oil well equipment, or data collected later), obtains a maximum threshold curve and a minimum threshold curve based on the fitting curve obtained by the mathematical model, and when the cloud server detects that the current and temperature variables of a certain Internet of Things electromagnetic relay are outside the maximum threshold curve and the minimum threshold curve, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay.

[0062] A remote monitoring system is provided for use in the mining field. The load circuit in the remote monitoring system is a mining equipment circuit. The status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, a temperature signal, a vibration frequency signal and a gas smoke concentration signal. The current signal is used to feedback the on / off status of the Internet of Things electromagnetic relay and the on / off status of the mining equipment circuit. The temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the mining equipment. The vibration frequency is used to reflect whether abnormal vibration occurs in the working environment of the Internet of Things electromagnetic relay and the mining equipment, such as a landslide causing the Internet of Things electromagnetic relay to vibrate, or the Internet of Things electromagnetic relay vibrates when it falls due to external reasons. The gas smoke concentration signal is used to reflect whether abnormal gas exists in the working environment of the Internet of Things electromagnetic relay and the mining equipment, such as a leakage causing one or several gases to reach a monitored concentration. The user sets up through the operation platform, groups the Internet of Things electromagnetic relays connected to the cloud server for controlling mining equipment, sets up a mathematical model that uses Newton interpolation method to fit the collected current, temperature, vibration and gas smoke concentration information for monitoring (which may include previously stored data of mining equipment as well as data collected later), and obtains the maximum threshold curve and the minimum threshold curve based on the fitting curve obtained by the mathematical model. When the cloud server monitors that the current, temperature, vibration frequency and gas smoke concentration variables of a certain Internet of Things electromagnetic relay are outside the maximum threshold curve and the minimum threshold curve, it issues a warning message and / or disconnects the Internet of Things electromagnetic relay.

[0063] Of course, the remote monitoring system of the present application can also be applied to heating furnace equipment, and can also be used in places where it is difficult for operators such as wind energy to reach, or such as meteorological or geological disaster monitoring equipment, and it is inconvenient for detection personnel to reach the site.

[0064] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. An Internet of Things electromagnetic relay, characterized in that: The invention comprises a housing (1), an electromagnetic relay body (2) arranged in the housing (1), a NB-IOT communication module and a sensor, wherein the NB-IOT communication module is used to establish a connection with a cloud server, and the NB-IOT communication module comprises a signal acquisition circuit, a microcontroller and a NB-IOT chip. When the electromagnetic relay body (2) is powered, the signal acquisition circuit acquires state information of the electromagnetic relay body (2) through the sensor, and the microcontroller collects and processes the state information of the electromagnetic relay body (2) acquired by the signal acquisition circuit, and sends the state information to the cloud server through the NB-IOT chip.

2. The Internet of Things electromagnetic relay according to claim 1, characterized in that: The electromagnetic relay body (2) comprises a contact group (22) and a coil for controlling the electromagnetic relay body (2) to be energized. The signal acquisition circuit comprises a current sampling circuit and a voltage sampling circuit. The state information of the electromagnetic relay body (2) acquired by the signal acquisition circuit through a sensor comprises a current signal of the contact group (22) and the number of energization times, and a voltage signal of the coil and the number of energization times. The current sampling circuit is used to acquire the current signal of the contact group (22) and the number of energization times, and the voltage sampling circuit is used to acquire the voltage signal of the coil and the number of energization times.

3. An Internet of Things electromagnetic relay according to claim 1 or 2, characterized in that: The sensor comprises at least one current sensor, the current sensor being used to collect current signals from a contact group (22) of an electromagnetic relay body (2), the current sensor transmitting the current signals from the contact group (22) to a signal collection circuit and the microcontroller performing signal processing.

4. The Internet of Things electromagnetic relay according to claim 3, characterized in that: Each time the contact group (22) of the electromagnetic relay body (2) is energized, the current sensor transmits the detected current signal to the signal acquisition circuit and the microcontroller performs signal processing. After processing by the microcontroller, the NB-IOT communication module uploads a signal as the number of times the contact group (22) is energized to the cloud server. The cloud server accumulates and counts the signal of the number of times the contact group (22) is energized for calculating the electrical life.

5. The Internet of Things electromagnetic relay according to claim 3, characterized in that: The current sensor is a sampling resistor (4) connected to a signal acquisition circuit, the sampling resistor (4) being a manganese copper sampling resistor, one end of the sampling resistor (4) being connected to a lead pin (21) of an electromagnetic relay body (2), the other end of the sampling resistor (4) being connected to a contact group (22) of the electromagnetic relay body (2), and two signal acquisition terminals (41) being provided on both sides of the sampling resistor (4) for connection to a microcontroller.

6. The Internet of Things electromagnetic relay according to claim 5, characterized in that: The lead pin (21) of the electromagnetic relay body (2) is an electrical connection sheet, and a second electrical connection sheet is provided at the other end of the sampling resistor (4). The manganese copper sampling resistor is in sheet shape and has the same thickness as the electrical connection sheet and the second electrical connection sheet. The sampling resistor (4) forms an integral body with the electrical connection sheet and the second electrical connection sheet. A first signal collection end is provided at the upper end of one side of the sampling resistor (4) perpendicular to the protrusion of the sampling resistor (4), and an L-shaped second signal collection end is provided at the lower end of the other side of the sampling resistor (4). The L-shaped second signal collection end includes a vertical section and a horizontal section connected in an L shape, the vertical section is parallel to the other side of the sampling resistor (4) and is connected to the lower end of the other side of the sampling resistor (4), and the horizontal section is parallel to the first signal collection end.

7. The Internet of Things electromagnetic relay according to claim 1, characterized in that: An installation cavity (11) and a protective cover (12) for covering the installation cavity (11) are provided in the housing (1); a PCB board (3) is installed in the installation cavity (11); a sensor and an NB-IOT communication module are integrated on the PCB board (3); the PCB board (3) and the electromagnetic relay body (2) are separated and arranged in the housing (1) by the protective cover (12); and the lead pins (21) of the electromagnetic relay body (2) are connected to the PCB board (3).

8. The Internet of Things electromagnetic relay according to claim 7, characterized in that: The PCB board (3) is connected to the coil for collecting voltage signals at both ends of the coil. Each time the coil of the electromagnetic relay body (2) is energized, a signal representing the number of times the coil is energized is uploaded to the cloud server by the NB-IOT communication module after being processed by the microcontroller. The cloud server counts the signal representing the number of times the coil is energized and accumulates the count for calculating the mechanical life span.

9. The Internet of Things electromagnetic relay according to claim 1, characterized in that: The sensor also includes one or more of a temperature sensor, a humidity sensor, a gas smoke sensor, and a vibration sensor; the temperature sensor is a temperature sensor for collecting the temperature inside the housing (1); the gas smoke sensor is used to sense whether there is some or certain smoke in the environment; the humidity sensor is used to sense the ambient humidity; the vibration sensor is used to sense whether there is abnormal vibration in the application environment; the temperature sensor, humidity sensor, gas smoke sensor, and vibration sensor transmit the collected signals to the microcontroller for processing, and after being processed by the microcontroller, the NB-IOT communication module uploads them to the cloud server.

10. The Internet of Things electromagnetic relay according to claim 1, characterized in that: The NB-IOT communication module also includes a power supply circuit, the input end of the power supply circuit is connected to the coil of the electromagnetic relay body (2), and the output end of the power supply circuit is connected to the signal acquisition circuit, the NB-IOT chip, and the control circuit of the microcontroller. When the coil is energized, the power supply circuit supplies power to the signal acquisition circuit, the NB-IOT chip, and the microcontroller, and the NB-IOT communication module establishes a connection with the cloud server.

11. A remote monitoring system, characterized in that: It includes a cloud server for receiving status information uploaded by the Internet of Things electromagnetic relay as described in any one of claims 1 to 10, wherein the Internet of Things electromagnetic relay is connected in a load circuit to control the power supply of the load device, and the cloud server can send a control signal to the Internet of Things electromagnetic relay to turn on or off the load circuit, and when the cloud server monitors that the status information uploaded by the Internet of Things electromagnetic relay exceeds a preset threshold or reaches an alarm value, it sends out a warning message and / or disconnects the Internet of Things electromagnetic relay.

12. A remote monitoring system, characterized in that: The invention comprises a cloud server for receiving status information uploaded by the Internet of Things electromagnetic relay as claimed in claim 9, wherein the cloud server groups a plurality of Internet of Things electromagnetic relays connected to the network, and sets a current threshold and a temperature threshold of each group of Internet of Things electromagnetic relays respectively. When it is monitored that the current information uploaded by a certain Internet of Things electromagnetic relay is greater than the current threshold of the corresponding group, or is less than the current threshold of the corresponding group, or when it is monitored that the temperature information uploaded by a certain Internet of Things electromagnetic relay is greater than the temperature threshold of the corresponding group, or is less than the temperature threshold of the corresponding group, an early warning message is issued and / or the Internet of Things electromagnetic relay is disconnected.

13. A remote monitoring system according to claim 12, characterized in that: The cloud server groups multiple networked IoT electromagnetic relays, analyzes the collected current and temperature data of the IoT electromagnetic relays in the same group and generates a mathematical model. When it is monitored that the temperature and current information of the IoT electromagnetic relays in the group obviously exceeds the corresponding threshold of the mathematical model, an early warning message is issued and / or the IoT electromagnetic relays are disconnected.

14. A remote monitoring system according to claim 12, characterized in that: The cloud server makes a mathematical model of the fitting curve based on the collected status information, and fits the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration information as variables to obtain a fitting curve, and obtains a maximum threshold curve and / or a minimum threshold curve based on the fitting curve by moving it at a certain proportion, such as obtaining the maximum threshold curve by translating it upward and obtaining the minimum threshold curve by translating it downward. When the cloud server monitors that the temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration variables of a certain IoT electromagnetic relay in the group are outside the maximum threshold curve and the minimum threshold curve, an early warning message is issued and / or the IoT electromagnetic relay is disconnected.

15. A remote monitoring system according to claim 12, characterized in that: The cloud server groups multiple networked IoT electromagnetic relays, and obtains variable thresholds by fitting temperature and / or current and / or humidity and / or vibration frequency and / or gas smoke concentration information according to a set mathematical model used by the group and the set mathematical model. When it is monitored that the fitting variables of the IoT electromagnetic relays of the group obviously exceed the corresponding variable thresholds of the mathematical model, an early warning message is issued and / or the IoT electromagnetic relays are disconnected.

16. A remote monitoring system according to claim 12, characterized in that: The cloud server records the original state parameters of the Internet of Things electromagnetic relay and the original parameters of the load device connected to the load circuit. The cloud server calculates the electrical life of the Internet of Things electromagnetic relay and / or the load device through the state information uploaded by the Internet of Things electromagnetic relay.

17. A remote monitoring system according to claim 12, characterized in that: The load circuit in the remote monitoring system is a sewage valve circuit, and the status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, and the current signal is used to feedback the opening and closing status of the Internet of Things electromagnetic relay and the opening and closing status of the sewage valve circuit; and or, the cloud server records the number of times the sewage valve circuit is opened based on the acquired current signal, which is used to calculate the life of the sewage valve.

18. A remote monitoring system according to claim 17, characterized in that: The status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes humidity signals and gas smoke concentration signals, which are used to detect whether there is a leak in the sewage valve near the Internet of Things electromagnetic relay. When the cloud server determines that there is an abnormality based on the humidity signal and gas smoke concentration signal, it will issue an alarm or directly shut down the Internet of Things electromagnetic relay.

19. A remote monitoring system according to claim 12, characterized in that: The load circuit in the remote monitoring system is a petroleum equipment circuit. The status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal and a temperature signal. The current signal is used to feedback the opening and closing status of the Internet of Things electromagnetic relay and the opening and closing status of the petroleum equipment circuit. The temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the oil well equipment.

20. A remote monitoring system according to claim 12, characterized in that: The load circuit in the remote monitoring system is a mining equipment circuit. The status information uploaded by the Internet of Things electromagnetic relay to the cloud server includes a current signal, a temperature signal, a vibration frequency signal and a gas smoke concentration signal. The current signal is used to feedback the on and off status of the Internet of Things electromagnetic relay and the on and off status of the mining equipment circuit. The temperature signal is used to feedback the temperature of the Internet of Things electromagnetic relay and the temperature of the mining equipment. The vibration frequency is used to reflect whether abnormal vibration occurs in the working environment of the Internet of Things electromagnetic relay and the mining equipment. The gas smoke concentration signal is used to reflect whether there is abnormal gas in the working environment of the Internet of Things electromagnetic relay and the mining equipment.

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