Supported Redundant Ciu 888 Topologies Of Deployment; Host Port Redundancy With Redundant Ciu 888S And Host Port Redundancy On Demand Of Host System - Honeywell CIU 888 Migration Manual

FIGURE C-2
C - 2
C.2 Supported redundant CIU 888 topologies of deployment
The following redundant CIU 888 topologies of deployment are
supported:
RS-232 host port redundancy with redundant CIU 888s and host port

redundancy on demand of host system (see section C.2.1)
RS-232 host port redundancy with redundant CIU 888s and data

synchronization by host system (see section C.2.2)
C.2.1 RS-232 host port redundancy with redundant CIU 888s and host port
redundancy on demand of host system
In this configuration, both CIU 888s in the redundant configuration are
connected to the same host system, i.e. Entis Pro (see FIGURE C-2).
The CIU 888s are connected to the host system via one of their fixed
host ports. Each host port has its own unique RTU address and is
configured for communication through Modbus RTU on serial.
RS-232 Host port redundancy with redundant CIU 888s and host port redundancy on
demand of host system
This configuration is compliant with Entis Pro. By issuing the
appropriate Modbus command, Entis Pro can demand to switch over to
the secondary CIU 888 if the primary CIU 888 is not responding
anymore and move to Com2/Port 42 to acquire tank data. The
Ensite Pro to CIU 888 Migration Manual
CIU 888
Part No.: 4417593_Rev09