System specification
The overall system is divided into three parts: remote point, wireless transmission link, and central control room.
The remote monitoring point is divided into three parts: data collector, GPRS data transmission equipment, and solar power equipment. Data Collector We use the sensors (Model 3001 LTC of the Solinst LTC Conductivity Levelogger) with internal battery support (up to 8 years of power supply) to monitor the groundwater level. This sensor can store 4000 data, and can design the acquisition time interval. The GPRS data transmission device can upload the collected data according to the upload time interval set by the user and the data transmitter power supply adopts the solar power supply mode, which is suitable for working in an unattended environment in the field.
Wireless transmission links use GPRS data transmission. The remote monitoring point data transmission equipment sends data to the GPRS network, and then it is converted into the Internet network through service conversion and transmitted to the application server, and the GPRS data server forwards the data to the client device. Realize wireless data communication between the central control room client software and the remote monitoring point GPRS data transmission device.
The central control room is equipped with a GPRS data receiving server and a computer client. The client software can be used to collect, monitor, and handle the site. At the same time, the client software needs to implement functions such as data storage and vertex diagrams. The central control room uses a GPRS data server to provide data connectivity for wireless links. The GPRS data server adopts an embedded implementation task operating system and uses an independent communication protocol for data communication. Therefore, various types of virus software on the network are prevented from being attacked and the security is high. Avoid a lot of system maintenance work caused by virus attacks. The GPRS data server needs fixed IP to solve the communication problem of the remote terminal equipment.
Functional structure of each part
1, GPRS data transmission equipment structure
The GPRS data transmission device is powered on only when it needs to send data. This function is controlled by the CPU control unit. When the CPU control unit transfers data and collects data, it enters the power saving mode to save battery power. When the CPU control unit is waken up according to the time set by the user, the data is serially collected, stored, or GPRS wirelessly logged in, and the data is uploaded after login. The GPRS data transmission device has dual serial ports and has two indicators: power indicator and online indicator.
The data transmission equipment is a wireless data acquisition and transmission terminal based on GPRS. It adopts the "MCU + GPRS Modem" scheme to receive user data through the RS232 port, and then uses the data as an IP packet to access the GPRS network through the GPRS module.
2, GPRS data server structure
The GPRS data server takes the existing PLC board as the core control, and the watchdog monitoring PLC will reset if there is an abnormality. At the same time, the device housing needs to have a liquid crystal screen display and indicator light display. The indicator light is controlled by the PLC and the watchdog, respectively: power indicator, network indicator, and working indicator. The working status indicator flashes once every second for 1 second, indicating that the watchdog is working properly. Watchdog is mainly used to prevent the terminal system from crashing, and the power management realizes regular wake-up and sleep modes.
3, client software
The console software and the database setup carrier are computers. It has the functions of setting the time for the online and offline transmission of the transmission equipment, the IP address, and the set equipment name of the port; setting the data acquisition function; collecting the data for storage; manually collecting the current data; data query; operating logs and other functions.
System specifications
1, GPRS data transmission equipment
* Microcontroller: Use ATMAG128L, 7.3728Mhz.
* Communication module: ZTE ZTE ME3000.
* Power supply: DC6V lead-acid battery.
* Data interface: Two RS232 interfaces, can simultaneously connect two sub-devices; baud rate is 9600bps.
*LED indication: Power indicator, online indicator.
* Antenna interface 50Ω/SM5 female.
* SIM card holder.
* Operating temperature: -30°C ~ +70°C.
*Working relative humidity: 95%@+40°C.
2, client software
* Display ratio: more than 800×600
* Operating System: Window 2000/XP
* Recommended configuration: RAM 512MB, CPU P4, 1 Ethernet port, 1 serial port.
* Minimum configuration: RAM 256MB, CPU P3, 1 Ethernet port, 1 serial port.
* Network requirements: The GPRS wireless data acquisition console software requires 24-hour real-time online to ensure that the remote point data transmitter transmits data to the GPRS wireless data acquisition console software for storage.
System experience, please visit:
Contact: Zhu Haoran
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