Precautions for the use of soil moisture transmitter RS485 output: First, the single RS485 bus of the soil moisture transmitter must adopt a “hand-in-hand” bus structure, that is, the management computer is connected to the No. 1 controller, No. 2 is connected to No. 1, No. 3 is connected to No. 2, and so on. Second, the wire of the soil moisture transmitter must be multi-stranded shielded twisted pair network cable with a wire diameter of 0.3 square millimeters or more (multi-stranded is for backup). Apply PVC pipe separately to avoid walking with strong electricity to avoid interference with strong electricity. Third, if there are multiple slaves or the connection line is too long and the communication is not smooth, it is necessary to add 120 ohm matching resistors between the 485 (A) and 485 (B) of the first and end of the soil moisture transmitter 485 bus to improve the communication quality. (Must be twisted pair) Fourth, the reasonable arrangement of the data transmission rate, the number of load nodes and the transmission distance of the soil moisture transmitter achieves the principle of long-range low-speed and few-node, short-range high-speed multi-node. It should be noted that the alternating current and chassis powered by the soil moisture transmitter equipment must be truly grounded and well grounded. There are many places where there are triangular sockets on the surface, but in fact there is no grounding at all, be careful. When the soil moisture transmitter is well grounded, it can ensure that the equipment is affected by lightning surges and static electricity accumulation, and can better release energy with the lightning protection design of the equipment to protect RS485 bus equipment and related chips from damage. If the soil moisture transmitter is not connected or connected to the ground, do not use the RS485 bus to avoid equipment burning and casualties. Product consultation, product customization, agent, technical inquiry, quotation, etc. If you have any questions, please contact Xingyi: 400-600-4496!