table of Contents
2. 4-20mA analog signal to LoRa collector RAK7422/TAK7432
Preface
In the industrial production process, temperature, as an important physical parameter, is closely related to major technical indicators such as safe production, product quality, and production efficiency . Accordingly, temperature measurement based instrument is widely used . However, due to the slow response, low accuracy, and low efficiency of traditional temperature measuring instruments, they can no longer adapt to the rapidly developing modern industry. With the rapid development of sensor technology , a new type of thermal resistor ( thermal resistor ) temperature measuring element is not only easy to operate, but also the accuracy is greatly improved. The temperature measurement principle of thermal resistance is based on the characteristic that the resistance value of conductor or semiconductor changes with temperature to measure temperature and temperature-related parameters. The resistance value can be converted into a 4mA ~ 20mA signal for the instrument to collect and read through the transmitter . Therefore, resistance thermometers are widely used in industry.
However, the data obtained by thermal resistance thermometers is analog data, and its data transmission has certain difficulties. Traditional transmission networks often use wired transmission and wireless transmission. When the scope of application in industrial production continues to expand, thermal resistance thermometers will also continue to expand coverage Area, the transmitter equipment that converts the resistance value into a 4mA ~ 20mA signal needs more. Moreover, conventional communication network, e.g. Wifi network, since the communication distance it can cover a single router is very short, mass transport is slow, poor load , only tens of meters, and therefore, when a wide range, it needs more Routers, which will greatly increase the complexity of the network and greatly increase the cost.
So, can we build an industrial temperature data transmission system with the help of a LoRaWAN network with a long communication distance (ten kilometers in the suburbs and a few kilometers in the urban area)?
The answer is feasible. This article describes how to build a LoRaWAN network transmission system for industrial temperature simulation data.
1. Introduction to the basic structure of the LoRaWAN network transmission system for industrial temperature simulation data
As shown in Figure 1, the traditional temperature sensor can be docked with analog signals to LoRaWAN converters, LoRaWAN gateways, and servers to build a LoRaWAN network transmission system for industrial temperature analog data. If you buy RAK Ruike Hui associated company RAK7422 / RAK7432 ( 4 mA ~ 20mA analog signal to LoRa collector ) products and RAK7249 LoRa gateway, you can quickly build a LoRaWAN network, simultaneous acquisition of multiple 4mA ~ 20mA signal will be 4mA ~ The 20mA analog signal is transmitted to the LoRa data collector, through the built-in server management node of RAK7249 , and the decrypted data is sent to the application server through the 4G network.
Among them, the analog signal to LoRaWAN converter can be, for example, the new product RAK7422/RAK7432 ( 4-20mA analog signal to LoRa collector ) that will be launched by RAK Huilian , which can convert the 4-20mA current signal into which the resistance value is converted . It becomes a wireless LoRa signal to realize the wireless data collection of industrial field sensors.
RAK7249 LoRa Gateway is an intelligent gateway developed by RAK Huilian. It has low power consumption, long life, and two-way data transmission, which provides a reliable guarantee for the accurate collection of real-time data. You can remotely control and manage the LoRa gateway for easy management. For more detailed introduction, please refer to RAK7249 industrial grade LPWAN gateway .
If it is not the conversion of analog signals to LoRaWAN, but the conversion of data from RS485 interface to LoRaWAN, for example, you can consider the product RAK7421 that has been launched by RAK Huilian. RAK Rui Ke Hui Lian RAK7421 industrial-grade RS485 to LoRaWAN data collector, can convert RS485 protocol data into LoRaWAN wireless messages, and send the data to the cloud server through the LoRa Gateway. The cloud server can also actively send data to the RS485 terminal to achieve two-way data transparent transmission. For more introduction, please refer to " Why do you need a data collector from RS485 to LoRaWAN ".
2. 4-20mA analog signal to LoRa collector RAK7422/TAK7432
RAK Ruike Hui linked RAK7422 / RAK7432 new product can be as in FIG. 2 products networking, temperature converter , converting heat resistance value of 4-20mA signal is integrated by the internal precision op amps acquisition 4-20mA The analog signal is converted into a digital signal and encapsulated into a LoRaWAN data packet. Through the LoRaWAN wireless network, the field temperature value is sent to the back-end server, which is convenient for users to use.
RAK7422/RAK7432 products have built-in high-precision operational amplifiers . The 4-20mA reading accuracy specifications are as follows :
Conclusion
This article introduces the LoRaWAN network transmission system for industrial temperature analog data . RAK RAK7422 /RAK7432 ( 4-20mA analog data to LoRa collector ) product can convert the 4-20mA current analog signal converted by resistance value into a wireless LoRa signal , Realize the wireless data collection of industrial field sensors . Compared with the traditional transmission method, not only the scope is wide, but the cost is also greatly saved.