Dahua Technology DH-IPC-HDEW Series Quick Start Manual page 37

Appendix 2.3 FAQ on RS-485 Cable
Malfunction
The Camera can
perform self-
check, but is out
of control.
The Camera can
be controlled, but
the operation is
not smooth.
Appendix Table 2-1Malfunction, possible reason and solution
Possible Reason
Baud rate/address of the host and
Camera are not matched.
Positive electrode and negative
electrode of RS-485 cable are
misconnected.
Loose connection.
RS-485 cable is broken.
RS-485 cable is in poor contact.
A RS-485 cable is broken.
The distance between the host
and Camera is too long.
Too many cameras are connected
parallelly.
30
Quick Start Guide
Solution
Modify the baud rate/address of the host
or Camera to be matched.
Connect cables to the positive electrode
and negative electrode correctly.
Connect the cables firmly.
Replace RS-485 cable.
Connect the RS-485 cable firmly.
Replace RS-485 cable.
Install terminal resistance.
Install RS-485 distributors.