Rockwell Automation Safety Function Application: Stop Category 0 with PowerFlex Drives

Overview

This document outlines an application technique for implementing Safety Stop Category 0 for actuator subsystems. It focuses on integrating Rockwell Automation's PowerFlex 525 and PowerFlex 527 drives, equipped with Safe Torque-off (STO) functionality, with Guardmaster dual-input safety relays and expansion modules.

Designed for advanced users familiar with safety system requirements, this guide details the safety function's realization, requirements, and functional description, adhering to standards like ISO 13849-1.

Key Components & Standards

• Drives: PowerFlex 525 and PowerFlex 527 with Safe Torque-off (STO)
• Safety Relays: Guardmaster Dual-Input Safety Relay (GSR DI) and Guardmaster Expansion Module (GSR EM)
• Input Device Example: SensaGuard switch
• Safety Standards: Compliance with ISO 13849-1 (Category 3, PLd), ISO 14119, ISO 18355, and ANSI B11.19.

Functionality

The application demonstrates how to achieve a Category 0 stop (power removal, coast to stop) through a hardwired connection to the STO inputs of the drives. It covers essential aspects such as risk assessment, safety function requirements, system configuration, and verification/validation plans to ensure reliable operation and safety.

Resources

For detailed installation, configuration, and troubleshooting, refer to the comprehensive list of Rockwell Automation publications provided within the document.