Wireless data acquisition refers to the use of wireless data acquisition modules or equipment to collect and remotely transmit the voltage, current and other physical quantities output by sensors in the industrial field.
Most of the wireless data collectors are portable, which can transmit the data collected on the spot to the computer in real time. Compared with ordinary portable data collectors, wireless data collectors further improve the operator's work efficiency, so that the data can be changed from the original local verification and storage to remote control and real-time transmission.
1. Introduction to Wireless Data Acquisition
Wireless data acquisition refers to the use of wireless data acquisition modules or equipment to collect and remotely transmit the voltage, current and other physical quantities output by sensors in the industrial field.
Most of the wireless data collectors are portable, which can transmit the data collected on the spot to the computer in real time. Compared with ordinary portable data collectors, wireless data collectors further improve the operator's work efficiency, so that the data can be changed from the original local verification and storage to remote control and real-time transmission.
The reason why the wireless data collector is called "wireless" is because it does not need to rely on the communication port PC for data exchange like ordinary portable data collectors, but can directly communicate with PC and server through the wireless network in real-time data communication. To use the wireless handheld terminal, a wireless network must be established first. The login point of the wireless network device is equivalent to a bridge connecting the wired local area network and the wireless network. It is connected to the wired network through a twisted pair or coaxial cable, and the wireless handheld terminal exchanges data through the wireless communication with the AP and the server of the local area network. .
The wireless data collector has strong real-time communication data and high efficiency. The wireless data collector directly exchanges data with the server, and the data is transmitted in real time. The data obtained by the operation on the wireless data collector will enter the background database at the first time, that is to say, the wireless data collector extends the data information system to the hands of every operator. The hardware technical characteristics of the wireless data collector are the same as the portable ones, including CPU, memory, screen display, input device, output device, etc. Each wireless data collector is a network node with its own IP address, and realizes real-time data exchange with the network system through AP.
2. The working principle of wireless data acquisition
The software functions of the data collector are generally divided into two parts: operating system and application software.
2.1 Operating system
There is no uniform standard for operating systems. Since data collectors use key components such as CPUs and motherboards independently developed and produced by various manufacturers, most operating systems use different standards. Some manufacturers have also launched operating systems based on the PALM/WinCE platform, but these products are still aimed at data management applications and are not very suitable for data collection in the traditional logistics field. At the same time, due to the relatively high power consumption of such products, and for ordinary operators, the above two platforms are too complicated and require a large amount of maintenance to use. Therefore, they are rarely used in the field of logistics supply chain, and are mostly applied Office automation field.
2.2 Application software
Application software is usually developed according to the user's application process. Software development tools generally use C language or other languages. For the application of data collectors, with the more extensive combination of barcode technology and IT technology, portable data collectors will be more widely used, and will be more closely integrated with industry applications, becoming a part of industry solutions.
The data collector is combined with the user's application system and plays a huge role in each application link of the user's supply chain. With the rapid development of information technology and the increasing popularity of enterprise informatization.
3. Wireless Data Collector
The wireless data collector can be roughly divided into two parts:
3.1 Acquisition part, such as PLC, acquisition card, analog-to-digital converter, etc. can be used as acquisition part.
3.2 The core part is the wireless transmission part, in the form of radio, ZIGBEE, 2G, 3G, WIFI and so on. The most widely used in industry is the 2G transmission form.
4. Product Features of wireless data acquisition device
4.1 Three-layer system protection: On the basis of the original two-level (software protection + CPU built-in watchdog protection, external hardware watchdog protection) system protection, a first-level system monitoring protection SWP (System Watch Protect) is added to completely solve the problem. It solves the difficult problems such as "fake online", "fake crash" and "crash" in the industry.
4.2 High-speed processing CPU: Using high-speed ARM9 industrial-grade CPU, it can process data conversion of various protocols at a higher speed and avoid problems such as data retransmission and loss caused by slow CPU processing speed.
4.3 DNS automatic acquisition: automatically obtain DNS, no need to manually configure and input DNS, avoid the serious phenomenon of DTU equipment crash due to the abnormal selected DNS server.
4.4 Perfect protocol stack: The new system is loaded with a perfect TCP/IP protocol stack, adopts a perfect TCP/IP protocol stack, and has excellent network communication performance.
4.5 Excellent EMC performance: It has passed the 3000V electric shock test, especially suitable for use in harsh industrial environments, and the system is stable and reliable.
4.6 Support multi-center: customer data can be sent to the monitoring center designated by the customer at the same time, and the maximum number of sending centers is 256.
5. Application of wireless data acquisition device
Electric power monitoring; oil field monitoring; remote meter reading; street lamp monitoring; environmental monitoring; meteorological monitoring; water conservancy monitoring; heating network monitoring; electricity meter monitoring; computer room monitoring; traffic indication; coal monitoring; Real-time monitoring of noise; monitoring of key pollution sources in environmental protection; real-time transmission monitoring of water supply pipe network, and automatic remote control system of power distribution network.
