1) Check whether the serial port is set incorrectly (determine the serial port used).

2) Check whether there is a short circuit or an open circuit on the access control communication bus (to eliminate the short circuit and open circuit of communication lines).

3) Check whether the communication chip 75 184 of the RS485 communication card is damaged (replace the communication chip 75 148).

4)RS485 communication card is damaged (replace RS485 communication card)

2, personal access control communication impassability

1) Check the access control communication line for wiring errors (adjust wiring).

2) Check whether the access control communication chip 75 148 is damaged (replace the communication chip 75 148).

3) Check whether the access control read-write chip and module are damaged (replace the read-write chip and module)

4) Access control read-write board failure (replace access control read-write board)

5) Check whether the machine number has changed (adjust the machine number)

3, part of the access control communication can't

1) Check whether there is an open circuit in the middle of the access control communication bus (eliminate the open circuit phenomenon).

2) The communication line is too long or there are too many access control devices (RS485 amplifier is installed).

4, access card reading can't open the door.

1) After reading the card, check whether there is a voltage signal output from the reading pupil board (if there is no voltage output, replace the card reading board output circuits D880 and 90 13).

2) Check whether the external relay is damaged (replace the relay)

3) Check whether the external delay board is damaged (replace the delay board

4) Check whether the magnetic lock controller is damaged (replace the magnetic lock controller).

5) Electric lock failure (replace electric lock)

6) Electromagnetic lock chirping (increasing the power of access control power means replacing high-power transformer)

7) The red light flashes when reading the card (the access time, IC card authority and loss reporting shall be handled accordingly).