The PACSystems* RX3i Redundancy CPU can be used to 

perform real time control of machines, processes, and 

material handling systems. The CPU communicates with the 

programmer and HMI devices via a serial port using SNP 

Slave protocol. It communicates with I/O and smart option 

modules over a dual backplane bus that provides: 

▪ High-speed PCI backplane for fast throughput of new advanced I/O. 

▪ Serial backplane for easy migration of existing Series 90*-30 I/O. 

Features 

▪ Hot standby (HSB) redundancy. Two redundant units 

make up a redundancy system. Each unit requires one 

Redundancy CPU (IC695CRU320) and a redundancy 

Memory Xchange module (IC695RMX128/228) configured as a redundancy link. 

▪ Contains 64 Mbytes of battery-backed user memory and 

64 Mbytes of non-volatile flash user memory. 

▪ Provides access to bulk memory via reference table %W. 

▪ Configurable data and program memory. 

▪ Programming in Ladder Diagram, Structured Text, 

Function Block Diagram, and C. Refer to PACSystems RX7i 

& RX3i CPU Programmer’s Reference Manual, GFK-2950. 

▪ Supports auto-located Symbolic Variables that can use 

any amount of user memory. 

▪ Reference table sizes include 32Kbits for discrete %I and 

%Q and up to 32K words each for analog %AI and %AQ. 

▪ Supports most Series 90-30 modules and expansion 

racks. For a list of supported I/O, Communications, 

Motion, and Intelligent modules, refer to the PACSystems