Application Of Mitsubishi Fx3ga In Coal Mine Roadcar Protection Device

1. System Overview
The raw coal used in the underground coal mine is transported by the winch system. In order to protect the safety of personnel and equipment, the state clearly stipulates that the anti-sports device must be installed and used in the underground mine underground.Mitsubishi PLC</ Strong> During the transportation of the inclined lane, the mining vehicle traction wire rope breaks and a sports accident occurs. The parking bar of the sports car protection device should not be opened to intercept the uncontrolled mining car (blocking the car) Mitsubishi PLC
The maximum energy of each set of blocked car block intercepting out-of-control mine car is certain. According to the rated blockage energy of the car block, the parameters of the inclined lane and the running car parameters, it is theoretically possible to calculate the number of car lanes required to install the car lane. The actual underground mine is about 1km. Coal mine inclined shaft transportation roadway will generally be installed with more than 6~10 sets of car-bars in the coal mine.
2. Process characteristics
The winch transportation control system is generally installed in the operation room of the flat yard on the ground or underground inclined lane. In order to make the winch driver more objective and accurate to understand the operation of the mine car, most coal mines now use the video transmission system to transport the cars through the various blocks. The monitoring video uploading of the column shows that the video surveillance system of the coal mine underground generally uses optical fiber transmission in front of the winch driver, and cooperates with the monitoring block of the sports car protection device. Here, a control system of the sports car protection device based on the RS485 twisted pair transmission network is introduced. Judging the running position of the mine car, opening and closing the car bar in time to ensure the safety of transportation; at the same time uploading the operation status information of the car bar to the winch driver FX3GA
Transfer the status information of the car bar from the kilometer well to the winch room one by one ( The centralized control method of the control room is obviously not suitable. The networked distributed control method becomes the inevitable choice of FX3GA. The process requires that the transporting mine car must be lifted up and down when it is moved up or down to reach the closed parking bar. The mine car passed smoothly, the mine car completely passed the car bar and the rear car bar must be dropped and closed. The FX3GA is used as a safety protection device. Of course, reliability is first placed. Currently, the industry basically adopts a highly reliable PLC. Designed as a controller to develop a sports car guard control system.
It is the key of this system to judge whether the transportation ore car needs to open the car bar before reaching the car bar. At present, there are three main methods for positioning the mine car in the industry: encoder positioning, depth indicator positioning, and track sensor positioning. This article discusses the use of depth indicator positioning.
3, control system composition
Mitsubishi FX series PLC has a large market share in China. In this project, we use Mitsubishi FX3GA (FX3GA-24MR-CM) as the main controller, each main controller expands one RS485 communication port (FX3G-CNV-ADP + FX3U-485ADP-MB), and multiple controllers pass the extended RS485. The communication port is connected to the network (Mitsubishi calls it N:N network). The main station controller in the network is arranged in the transport winch control room to collect the position signal of the mine car; the substation controller is arranged near the block, the local control bar is lifted and lowered, and one substation controls one car bar. The master station controller FX3GA-24MR-CM programming port is connected to the Kunlun state HMI (TPC1061Ti) to display the status information of each car bar. The schematic diagram of the entire control system is shown in Figure 1.

Explosion-proof equipment used in coal mines Requirements, the entire system consists of the main control box, electric control box and operation box of the explosion-proof box. The main control box is the main station, the electric control box is the substation, and the operation box is equivalent to the upper computer. The main station and the substation are connected to the same brand PLC communication. The other station's other communication port (FX3GA-24MR-CM programming port) is connected to the host computer — Kunlun state state HMI (TPC1061Ti). A small PLC (DVP14SS211T) acquisition panel button signal is used in the operation box. Due to the requirement of isolation between the intrinsically safe circuit and the non-intrinsically safe circuit in the explosion-proof design, the intrinsically safe button signal on the operation box panel is isolated and converted into non-本Connect to the PLC (DVP14SS211T) after the signal is turned on. Kunlun On-state HMI (TPC1061Ti) A standard 9-pin serial port pin defines two communication interfaces. One RS232 (COM1) and one RS485 (COM2) are connected to the main station Mitsubishi PLC (FX3GA-24MR-CM) and the operation box. One Delta PLC (DVP14SS211T).
The winch works to pull the mining vehicle to carry the coal. The main station PLC receives the specific position signal from the mine car to the rear of the car, and issues the command to the corresponding substation PLC to control the corresponding car bar. The mine car passes through the car bar. The main station PLC receives the specific position signal of the mine car up to the front of the block, and issues a command to the corresponding substation PLC to control the corresponding car bar to be lowered. The mine car runs downwards, and the main station PLC receives the specific position signal of the mine car reaching the front of the block, and issues the command to the corresponding substation PLC to control the corresponding car bar to lift; the mine car successfully passes the block, and the main station PLC receives the mine car. After reaching the specific position signal behind the block, the command is sent to the corresponding sub-station PLC to control the corresponding car bar to be lowered. The status information of each car bar is transmitted to the main control PLC in a centralized manner, and is provided to the winch driver for monitoring by the HMI display. When the car bar fails, an audible and visual alarm is issued to remind the driver to do the corresponding processing.
The control box is equipped with a control panel, which can centrally control the movement and fault reset of all connected car lanes, and can also control the operation of a certain block car.
4, system commissioning
sub-station control block operation debugging
1) Correction motor running direction is consistent with the lifting lower block car command.
2) The car bar is lifted and lowered several times. After adjusting the fixed mechanical device, set the running time parameter of the bar in the PLC. (The time limit parameter of the upper and lower limit sensors on the car bar has this time parameter. The time can also stop the car. Column operation), set the substation PLC station number.
The position of the main station mine car position detection sensor is determined
The depth indicator rotates on the screw to fix a slider that does not rotate with the screw. The winch rotates forward, the mine car goes down, and the slider on the rotating screw Swipe down.
1) The mine car just runs to the bottom of the car bar. At this time, the winch is stopped. The position of the slider on the depth indicator screw represents the actual position of the mine car. An inductive proximity sensor is fixed at the end face of the slider, and the sensor sensing surface is aligned with the center of the slider end surface, so that the sensor can sense the output signal of the slider.
2) The position detection of each car block is the same. How many inductive proximity sensors are fixed on the car depth indicator in the roadway to determine the position of the mine car.
After the main station and sub-station are separately commissioned, they can be connected to the network to simulate the actual operation and see the operation effect.
5, system advantages
1) Networking between the same brand PLC (Mitsubishi FX3GA-24MR-CM), simple programming, reliable communication, high system stability.
2) Non-linear detection of mine car position, indirect use of inductive proximity sensor on the depth indicator to indicate the specific position of the mine car, simple structure, small impact from the surrounding environment, linear detection of mine car position reliability relative to the encoder It’s better.
3) Using a high-resolution touch screen to display the state of the mine car, the state of the car bar and the system parameters, simple and intuitive. There is almost no need to debug the site, just connect the communication line with the main station and provide power to work.
4) Mitsubishi's third-generation small PLC (FX3GA-24MR-CM) was selected and produced by Mitsubishi Electric Automation Machine Manufacturing (Changshu) Co., Ltd. at No. 3 Southeast Avenue, Changshu High-tech Industrial Development Zone, Jiangsu Province. This PLC has high cost performance, short lead time, built-in programming communication Mini-B small U port, use a common U port data cable without special programming cable (I used the data line of the old Nokia mobile phone) The program upload and download tasks can be completed, which is fast and easy to use.
5) The host CPU (FX3GA-24MR-CM) expands a special RS4 communication adapter FX3U-485ADP-MB through the FX3G-CNV-ADP connection. The FX3U-485ADP-MB supports the standard MODBUS protocol. The total extension distance is 500 meters. The Mitsubishi N:N network is used in this system. The communication is set at 9600 baud rate, and 6 (including the main substation) are connected. The communication is stable and reliable within the range of nearly 1000 meters underground. The whole set of equipment is running. normal.
6, summary
1) each brand HMI one-to-one connection to the major brands PLC believe that everyone is familiar. The HMI of this system is designed to be connected with two PLCs with different communication interfaces of different brands. The initial selection stage repeatedly checks the Kunlun state-of-the-art HMI (TPC1061Ti) communication port, confirming that one physical interface (D-type 9-pin interface) is integrated with one. RS232 (COM1) and one RS485 (COM2) two communication interfaces, the two PLCs are connected to the two communication interfaces and there is no theoretical problem. The connection between HMI and PLC is shown in Figure 2 below.

This structure is configured in HMI I encountered a lot of setbacks, and finally tried many times before I found the root cause of the problem.
Initially using the configuration structure of Figure 3, Delta PLC can be connected, and Mitsubishi PLC can not be connected. Since there is no previous experience of directly connecting the Mitsubishi programming communication port (RS422) to the host computer, the TPC1061Ti user manual is connected to the RS422 interface through the series resistor in the communication line. The series resistor is repeatedly replaced, and the Mitsubishi PLC is modified after the configuration. Can't connect.

Meditate carefully, two The PLC hardware interface is different, and the HMI needs to provide two different communication interfaces. This was considered in the initial selection stage, and the same error was made in the final configuration programming stage. How can a parent device (equivalent to a serial port) connect two different communication interfaces?
Switch to Figure 4 to configure the connection, the problem is solved immediately.

2)Familiar with FX2N series PLC Between the N:N network programming, the first attempt to use the FX3GA to implement the N:N network, after referring to the user manual, using the latter is basically no different from using the former, it is still very easy to implement, and the Mitsubishi FX controller N: One of the biggest advantages of the N network is that data can be exchanged directly between the substations without going through the main station. The link devices given in the Mitsubishi user manual are shown in Figure 5 below.

In the 1# slave station You can directly read the master station data or directly read the 2# slave data as shown in Figure 6:

The action 1 in the above figure shows that the data stored in the M1000~M1003 device of the master station is directly read out from the slave station in 1#, and output to Y010~Y013; In the 1# slave station, the input state quantity X000~X003 is stored in the 1# exchange area device M1064~M1067 for other stations; the action 3 means the direct reading in the 1# slave station is stored in the 2# slave station data exchange. The data in the area device M1128 to M1131 is output to Y020 to Y023.