The fuel dispensers produced by the company will use DTUs from various manufacturers. In order to better understand the communication situation, the company has specially developed a DTU for this purpose.
Its advantages: The networking is fast and flexible, the construction period is short, and the cost is low; the network coverage is wide; the security and confidentiality are good; the link supports always-on, billing based on traffic and low user cost.
In order to be more concise, we use more convenient communication modules and communication circuits and discard the CPU control module.
Communication module:
The communication module is the key to DTU’s data transmission, through which the data of the tanker can be sent to the server. There are many different communication modules in the market, and finally, we chose the WH-GM5 module with IoT. WH-GM5 is the first Cat.1 networking communication module launched by Youwu.com. The module software has complete functions and covers the most common application scenarios. Users can achieve transparent two-way data transmission from the serial port to the network through simple settings. Support 4-way Socket connection, more quickly transmit user data to the network.
Power supply part:
External power supply: DC 12V 150mA
Wide voltage power supply: DC 9-32V
Communication current: 150mA
Voltage circuit: 5.5V ~ 36V
Operating temperature: –40°C~ 125°C
The hardware interface uses a 3.81mm pitch 7p plug-in terminal; there are two different serial port communications: RS485 and RS232.
Baud rate range: 1200 ~ 460800bps configurable;
There are three check modes: odd check, even check, and no check; the stop bit can be 1 or 2 bits. A variety of hardware options can meet various device connections.
Appearance:
Choose an aluminum alloy shell, that is strong and reliable. There are also 5 indicators on the casing corresponding to the module power indicator, network signal indicator, server connection indicator, server connection indicator, and data transmission indicator. Users can know the working status of the DTU through these indicators.
Different DTU modules use different configuration software. In order to allow users to use it better, we compared the communication modules of various companies and finally chose the easy-to-use WH-GM5 module. In order to make the space occupancy rate of the actual installation smaller and the volume of the whole DTU more likely, we canceled the CPU circuit and adopted the automatic receiving and sending design of the hardware when selecting the RS485 communication of the serial port circuit. Finally, complete the following figure:
