These two Master Controllers are connected to common Remote I/O Bases, and to the SCADA system to create a hot standby controller configuration with common I/O.
Both Controllers consume the common input data from the remote I/O Bases, but only the active Controller controls the outputs, and communicates with the supervisory computer. The Secondary Controller continuously monitors the health of the Master Controller, and if a failure is detected, then the
Secondary Controller takes over control.
The Primary and Secondary Controllers stay synchronised through a separate communications link between the two Controllers. The monitoring, and switch-over between Primary and Secondary Controllers occurs completely transparently to the SCADA computer. The Secondary controller can either
run a program identical to the Primary Controller, or it can run an independent program designed to bring the process to a safe state.
The P3-R can be programmed in one or more of the standard IEC61131-3 programming languages (all 5 languages plus flow chart and PID auto tune)using the Omniflex ISaGraf Programmer’s Workbench, although conventional remote I/O systems can be implemented without the need for any
programming.
The P3-R CPU includes a powerful inter-network routing capability for retrieving data from the corners of the factory in very large, geographically spread-out installations. This capability allows many dissimilar network types to be linked to create a seamless factory intranet, often without the need to lay special network cabling.