The sensor cannot be connected to the PLC or computer
1) The computer has multiple COM ports, and the selected port isincorrect.
2) The device address is wrong, or there are devices with duplicateaddresses.
3) The baud rate, check method, data bit and stop bit are wrong.
4) The host polling interval and waiting response time are too short,generally more than 100ms.
5) The 485 bus is disconnected, or the A and B wires are connectedreversely.
6) There are too many devices or the wiring is too long, add a 485booster, and add a 120Ω terminal resistance (add 120Ω resistance to A and B.This resistance is not integrated on the motherboard
7) The USB to 485 driver is not installed or damaged.
8) The equipment is damaged.