1. Something wrong with the PTZ camera. 2. The baud rate, address, protocol settings of the front-end PTZ and device PTZ not matched 3. RS485 cable is incorrectly connected (reversed) 4. When multiple decoders are connected, the far end of AB cable of the PTZ decoder must add a 120 ohm resistor to remove reflection and aid impedance matching, otherwise it may make the PTZ control unstable.
1. The data size is to large. Stop recording and carry out a backup. 2. The data volume exceeds the backup storage capacity and it will cause burning errors 3. The backup device is not compatible. 4. The backup device is damaged.
1. The remote control address is not correct. 2. The remote control distance is too far or the angle is too offset. 3. The battery is flat. 4. The remote controller or the front panel of the DVR is damaged.