I used your MC-5824R two doors access controller to manage the access control using RS485 communication, but the device cannot be connected and the communication is abnormal, can you tell what went wrong?
Hello, thank you for using our company’s products, if RS485 communication is abnormal, please check according to the following situations
1. If the communication indicator RX light is always off, the serial port is selected incorrectly or the serial port is damaged or occupied by other programs, choose the correct serial port number and replace other serial ports (COM ports)
2. The communication indicator RX light is always on, and the RS485 bus A and B are connected reversely. Please follow the correct order, A connects A, B connects B
3. The communication indicator RX light is flashing, and there are too many devices in the RS485 bus, please reduce the number of access controllers or increase the signal amplifier
4. The communication indicator RX light is flashing, not bright or faintly always on, it may be that the RS485 converter is damaged, please replace the RS485 converter
5. The communication indicator RX light is always on or faintly always on, there are several situations: 1) The access control power supply is not grounded, please ground the access control power supply. 2) Computer leakage or power leakage, replace the power supply and ground. 3) There is strong external interference, the interference source should be eliminated, and the access control power supply should be grounded