The Snap PAC Redundancy Option Kit (Snap-PAC-ROK) can be used to design an Ethernet-based redundant control system.
Using standard S-series Snap PACs, Snap Ethernet I/O and the new PAC
Project Professional 9.0 software suite, users can employ the
Snap-PAC-ROK to configure automation systems with dual PACs that
essentially synchronize and run in parallel. If one controller fails or
is knocked off line, the other controller will assume command and
continue to execute the control program and the processes it runs with
no interruption or restart necessary. The Snap-PAC-ROK includes: a
Redundancy Arbiter, a standalone processor that connects serially to
both controllers, and monitors and regulates their status and maintains
synchronization of the control program during system start-up; and a
Redundant Power Switch, which allows power re-starts to controllers in
the event of failure and during firmware upgrades. The PAC Redundancy
Manager is a software utility for configuring redundant systems.
See related blog post, click here.
