Installation Manual

20
Figure 5-2
5.4
RS485 Bus FAQ
Phenomenon
Possible Reasons
Solution
Speed dome
can run self-
diagnosis but I
cannot control
it.
 Host address(baud rate) and
speed dome address(baud rate)
are not match;
 Positive and negative end of
RS485 Bus are misconnected;
 Connection cable is loose；
 RS485 Bus connection are cut
off;

Modify host or speed dome setup
；
 Switch RS485 positive end and
negative end；
 Fix connection cable firmly；
 Replace RS485 Bus.
I can control
the speed
dome but is not
smooth
 RS485 Bus connection are not
good；
 One RS485 bus is off；
 The distance between host and
speed dome is too far；
 Parallel connected too much
speed domes.

Connect RS 485 Bus again
；
 Replace RS485 Bus；
 Add terminal matching resistance；
 Add RS485 distributor.