Commissioning of a Redundant System Setup
Part No.: 4417593_Rev09
Ensite Pro to CIU 888 Migration Manual
CIU 888
3 - 5
$*6
A configured host port has its own unique RTU address and enables
Modbus on serial communication.
FIGURE 3-3
Schematic representation of a site with two pairs of CIU Plus and CIU Prime in a
redundant setup (Single host system)
On the CIU Prime, a maximum of four field ports are available to
connect to tank gauging instruments. The field ports can be configured
for GPU on Bi-Phase Mark communication or GPU on serial
communication.
In each pair, the CIU Prime and the CIU Plus are connected to one
another via one of the host ports of the CIU Prime and one of the field
ports of the CIU Plus.
NOTE: A cross-connection between the two pairs, in which the primary CIU Plus is
connected to the secondary CIU Prime and the secondary CIU Plus is
connected to the primary CIU Prime, is not supported.
3.3.1.2 Redundant pairs of CIU Plus and CIU Prime with redundant host systems
In this topology, two pairs of CIU Plus and CIU Prime are configured in a
redundant setup with corresponding host ports, field ports, tanks and
gauges. Each pair is connected to a separate host system (i.e.
