RS485-M and RS485-S are the same RS485 communication bus, providing two interfaces to facilitate cascading;
The RS-485 communication mode allows up to 32 instruments to be connected to a bus, which is connected to the host computer through an RS-485 converter. The communication cable can use ordinary shielded twisted pair, and the total length should not exceed 1200 meters. The positive and negative polarity of the RS-485 ports of each device must be connected correctly. If the shielded twisted pair is long, it is recommended to connect a resistance of about 120Ω at its end to improve the reliability of communication.
