Westermo RM-455U-D - Manual (Page 46)

Chapter Three Configuration
Man_455U-D Rev 3.04 Page 47
Note: The DIO channel is not available for any other purpose when the 455U unit
is connected to a redundant module.
If the Dual Redundant Control Connection becomes disconnected, then the two units will
remain in their previous active/in-active state.
Redundant units should be connected to separate power supplies and must be connected to
separate antennas and coaxial cables.
Although only one antenna will transmit at any one time, care must be taken with the
installation of the two antennas to avoid one antenna affecting the radiation pattern of the
other. The antennas should be installed at least 2 meters (6 feet) apart.
3.8.4 Dual Redundant Indications
To check the state of the Dual redundant system, you can:
TYPICAL REDUNDANT WIRING INSTALLATION
B
A

Earth
+24
+12
DIO
Power
Supply
24V
PRIMARY
455U
RS485
CONNECTION TO
HOST DEVICE
_
+
B
A

Earth
+24
+12
DIO
Power
Supply
24V
_
+
SECONDARY
455U
REDUNDANT
CONTROL
CONNECTION