Hardware Redundancy

The

AADvance-Trusted SIS Workstation software®

enables creating hardware redundancy from the

Equipment View

. When defining I/O modules to empty IO bus slots, there is an option of adding one, two, or three modules. Adding two (duplex arrangement) or three (triplex arrangement) modules enables redundancy, with each module carrying out the same function to improve reliability. When adding an I/O module having a duplex or triplex arrangement, the

AADvance-Trusted SIS Workstation software

automatically assigns the modules to the adjacent slots. For duplex or triplex groups, only configure one set of channels.

During redundancy, the processors read all the module inputs independently through the I/O bus. The processors then share the input data, application variables, and other communication data to agree on the data to use in the application. The processors run their logic independently, then share the outputs to send to the I/O and communications. Once they agree on the data, the processors individually send the output data, and then the next cycle starts.