ABB Processor 958481320201 350211080460 Safety CPU

The ABB Processor 958481320201 (350211080460) is a safety-rated CPU module from the AC500-S series. It is certified for SIL2 (IEC 61508) and PL d (ISO 13849-1), making it suitable for safety-critical applications such as emergency stop systems, light curtains, and safety interlocks. The CPU features a dual-processor architecture with cross-checking and integrated safety protocols.

Safety Architecture

The CPU uses a dual-channel lockstep architecture where two processor cores execute the same safety program and compare results at every step. Any mismatch triggers a safe state. The safety program is developed using certified function blocks in Automation Builder Safety Edition. The CPU can be used as a safety master for PROFIsafe devices or as a standalone safety logic solver.

Integration with Standard PLC

This CPU can operate in parallel with a standard AC500 CPU (via backplane) to combine safety and non-safety control in one rack. Alternatively, it can function as a standalone safety controller with its own I/O modules. The integrated PROFIBUS DP port supports PROFIsafe, allowing connection to safety-rated remote I/O and drives.

Application Domains

Typical applications include press control, robotic work cells, packaging machinery with guarding, and conveyor systems with emergency stops. The CPU is also used in process safety systems (e.g., burner management, high-pressure protection).