Sspa 1 sspa 2 – Paradise 205486 REV F User Manual
Page 83
Operations Manual, HPA2, Compact Outdoor SSPA
208495 REV C
83
8.1.2.3 PC Control using RS-485 and Paradise M&C Software
Applications requiring long cable runs between the computer and the 1:1 Redundant System
may use RS-485 communication. The Compact Outdoor Amplifier’s firmware supports
networking on a RS-485 bus. This type of network can be used to support the 1:1 Redundant
System.
The RS-485 link can typically be run up to 4000 ft. (1200 m) lengths. A good quality twisted
pair cable should be used along with proper line terminations. There are no parallel end
terminations in the amplifier’s RS-485 interface. Any required cable terminations have to be
added externally. Either full or half duplex RS-485 communication is supported. Schematics
showing the proper wiring of each version are shown in Figures 8-17 and 8-18.
As in the stand-alone redundant system of Section 8.1.2.1, each Compact Outdoor SSPA
must be programmed for Redundant System operation by using the RS-232 interface and
M&C program. Similarly when networking SSPAs on a RS-485 network, each amplifier’s
address must be set before they can communicate over the network. Both of these steps
should be performed together as part of the initial system setup.
Figure 8-17 shows a typical 1:1 Redundant System with RS-485 Full Duplex Communication.
Figure 8-18 on the following page shows a typical 1:1 Redundant System with RS-485 Half
Duplex Communication.
&
CONTROL
MONITOR
J4
J3
OUTPUT SAMPLE
J3
OUTPUT SAMPLE
A B
F
A
B
F
LINK
LINK
J5
J5
A
B
C
D
E
F
1
2
4
3
SSPA 1
SSPA 2
E
C
C
E
F
F
RF OUTPUT
SWITCH
&
CONTROL
MONITOR
J4
LINK
CABLE
SWITCH CABLE
T
E
U
F
TX +
TX -
RX +
RX -
T
E
U
F
TX +
TX -
RX +
RX -
To RX of Computer
To TX of Computer
SWITCH
J6
A2 (J6)
A1 (J6)
SWITCH
J6
Figure 8-17: 1:1 Redundant System with RS-485 Full Duplex Communication