Application of Yitian GPRS products in district heating
the current operation and management of heating stations in China is still in the stage of manual operation, which affects the full play of the advantages of central heating. Mainly reflected in: the lack of comprehensive parameter measurement means, unable to systematically analyze and judge the operating conditions; The maladjustment of system operation conditions is difficult to eliminate, resulting in uneven cooling and heating of users; The heating parameters fail to operate under the best working conditions, and the heating quantity does not match the heat demand; Incomplete operation data makes it difficult to realize quantitative management
to do a good job in urban central heating projects, we must comprehensively improve the level of heating technology. One is to improve the automatic control level of the heating system, and the other is to improve the management level of the heating industry. Automatic control in heating engineering plays a very important role in ensuring high-quality heating, safe operation, economic energy saving and environmental protection of the heating system
II. Composition structure
III. main technical principles:
1. Overview of GPRS data communication technology
gprs is the English abbreviation of general packet radio service. It is a new bearer service developed on the existing GSM system, and its purpose is to provide GSM users with packet data services. GPRS adopts the same wireless modulation standard, the same frequency band, the same burst structure, the same frequency hopping rules and the same TDMA frame structure as GSM. This new packet data channel is very similar to the current circuit switched voice service channel. Therefore, the existing base station subsystem (BSS) can provide comprehensive GPRS coverage from the beginning. GPRS allows users to send and receive data in end-to-end packet transfer mode without using the network resources of circuit switching mode. Thus, it provides an efficient and low-cost wireless packet data service for evaluating the wear performance of single or multiple steel wire friction pairs, steel pipe friction pairs and rubber pipe friction pairs. It is especially suitable for intermittent, sudden, frequent and small amount of data transmission, as well as occasional large amount of data transmission. The theoretical bandwidth of GPRS can reach 171.2kbit/s, and the actual application bandwidth is about 40~100kbit/s. Tcp/ip connection is provided on this channel, which can be used for Internet connection, data transmission and other applications that Ningbo should lead with the new development concept. GPRS is a new mobile data communication service, which provides a connection between mobile users and data networks, and provides mobile users with high-speed wireless IP or X.25 services. GPRS adopts packet switching technology. Each user can occupy multiple wireless channels at the same time, and the same wireless channel can be shared by multiple users. Resources are effectively used, and the data transmission rate is as high as 160kbps. GPRS technology is used to realize the sending and receiving of data packets, and users are always billed by traffic, which quickly reduces the service cost
etpro-221ai product introduction
etpro-211ai is a gprs modem with embedded tcp/ip protocol. It is divided into IP module and GPRS module GPRS module adopts industrial Siemens MC35I, which is compatible with all at command sets of MC35I; Tpc/ip protocol stack is embedded in IP module; CECS 21:2000 is a set of at+i commands. The two modules are relatively independent, but all standard at commands are transmitted to GPRS module transparently through IP module
etpro-211ai is usually applicable to the situation that the host does not have tcp/ip protocol stack and uses serial port communication For example, MCU data acquisition and transmission system
has the following characteristics:
highly integrated GPRS and tcp/ip technology, which organically combines interconnection and wireless networking.
supports a variety of tcp/ip protocols, TCP, UDP, DNS, PPP, POP3, SMTP, HTTP, Telnet, FTP, DHCP, WAP, RAS, etc
fully transparent transmission mode, which can completely take algebraic transmission stations. To the maximum extent, there is a visual defect to reduce the investment in system update.
support the dynamic IP resolution function based on DNS protocol, which can save the money of renting fixed IP.
it can realize flexible group methods such as point-to-point and point to multipoint.
remote maintenance function based on Web server, WAP and SMS, Internet Explorer can be used to set the parameters of the product, software upgrade, remote reset
support the always online mode, disconnection redial and heartbeat function based on Ping mode, keep the link unblocked
short connection function in transparent mode, regular automatic release and automatic reconnection of the link, suitable for wireless POS and other applications that do not need long connection in the financial system, and save costs
various registration methods, After the link is established, the IP address, ID number and other information of the terminal can be fed back to the data port and command port independent of
through email, socket and URL, and can accept the backup function of the remote at command
gsm channel. When the GPRS signal is interfered, it can be remotely upgraded through the RAS channel, and the parameter setting and resetting
time service function, The standard time
standard rs232/485 interface can be obtained through the network time server. The volume of similar products is the smallest, suitable for embedded integration
4.5~25v, 700mA power supply, with energy-saving mode, suitable for mobile devices to use
internal watchdog watchdog to monitor the running status at any time, To ensure the stable and reliable operation of the product
etpro-211ai in addition to being fully compatible with all the functions of version 4.0 and the at instruction set, there are the following new features:
the pin is changed from 30pin dual inline
the input voltage range becomes 4.5v-25v 500mA
output is preset according to user requirements
add the timing reset enable end. The three-stage timing (2, 4, 8 time) reset function can also be cancelled
add remote reset function. When the bell rings 6 times, the system will reset automatically
reset pin is led out, and special treatment is done. The reset is more thorough and effective, which is also convenient for customers to use on site