Allen-Bradley 1756-CNB/E, User Manual

Page: 30 / 186

Publication 1756-UM523F-EN-P - December 2006
30 Design the System
Placement of a Pair of
Redundant Chassis
With the standard redundancy module cables, a pair of redundant
chassis (primary and secondary) can function up to 100 m (300 ft)
apart.
Redundant Chassis Placement
If You Need More Than 100 Meters Between Chassis
To place the primary and secondary controller chassis more than 100
meters apart, use a custom fiber optic cable. For a custom cable,
follow these rules:
•
Keep total light loss through the cable less than or equal to 7dB.
•
Keep total length less than or equal to 4 km.
•
Use high quality 62.5/125 micron multi-mode fiber-optic cable.
•
Use professionally installed SC-style connectors to connect to
the 1757-SRM modules.
Redundancy Module Cable:
•
1757-SRC1 cable - 1 m (3 ft)
•
1757-SRC3 cable - 3 m (9 ft)
•
1757-SRC10 cable - 10 m (30 ft)
•
1757-SRC50 cable - 50 m (150 ft)
•
1757-SRC100 cable - 100 m (300 ft)
L
•
•
• E
N
B
T S
R
M
Redundant
Chassis A
Redundant
Chassis B
No Other Modules
C
N
B
L
•
•
• E
N
B
T S
R
M
No Other Modules
C
N
B