XVision XPS036, Руководство пользователя

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5. RS485 BUS TROUBLESHOOTING
Refer to following form:
Problem Possible Cause Solution
Dome cannot be
controlled
1. The address and baud rate settings of dome are
not in conformity with those of controller
2. The”+”and “-”connection of RS485 distributor
is incorrect
3. Wiring is not fully seated
4. There is breakage in the middle section of the
RS485 distributor
1. Change the address and baud rate of controller
or dome
2. Correct the connection
3. Make sure the connections are fully seated
The dome can be
controlled but the
operation is not
smooth
1. The RS485 distributor cable is not connected
properly
2. The RS485 distributor cable is faulty
3. The dome is too far away from the controller
4. There are too many domes connected in the
system
1. Secure the connection
2. Replace RS485 distributor cable
3. Add termination resistors to the system
4. Install RS485 distributor
4. PROBLEMS IN PRACTICAL CONNECTION
In some circumstances user adopts a star configuration
in practical connection. The termination resistors must be
connected to the two equipment that are farthest away
from each other, such as equipment 1# and 15# as shown
below. As the star configuration is not in conformity with the
requirements of RS485 standards, problems such as signal
reflections, lower anti-interference performance arise when
the cables are long in the connection.
The reliability of control signals is decreased with the
phenomena that the dome does not respond to or just
responds at intervals to the controller, or does continuous
operation without stop (Refer to the following picture):
In such circumstances the factory recommends the using
an RS485 distributor. The distributor can change the
star configuration connection to the mode of connection
stipulated in the RS485 standards.
NOTE: The RS485 distributor is not supplied with
the XPS036 Speed Dome.
The new connection achieves reliable data transmission
(Refer to following picture):
6#
Main
Controller
15#
32#
1#
Main
Controller
A+
A+
B-
120 Ω
120 Ω
120 Ω
1#
2#
16#