Rockwell Automation Publication 520-UM001I-EN-E - July 2016 235
Appendix G
Safe-Torque-Off Function
The PowerFlex 525 Safe-Torque-Off function, when used with other safety
components, helps provide protection according to EN ISO 13849 and
EN62061 for safe-off and protection against restart. The PowerFlex 525 Safe-
Torque-Off function is just one component in a safety control system.
Components in the system must be chosen and applied appropriately to achieve
the desired level of operator safeguarding.
PowerFlex 525 Safe-Torque-
Off Overview
The PowerFlex 525 Safe-Torque-Off function:
• Provides the Safe-Torque-Off (STO) function defined in
EN 61800-5-2.
• Blocks gate-firing signals from reaching the Insulated Gate Bipolar
Transistor (IGBT) output devices of the drive. This prevents the IGBTs
from switching in the sequence necessary to generate torque in the motor.
• Can be used in combination with other safety devices to fulfill the
requirements of a system “safe torque off ” function which satisfies
Category 3 / PL (d) according to EN ISO 13849-1 and SIL CL2
according to EN 62061, IEC 61508, and EN 61800-5-2.
For information on... See page...
PowerFlex 525 Safe-Torque-Off Overview
235
EC Type Examination Certification 236
EMC Instructions 236
Using PowerFlex 525 Safe-Torque-Off 236
Enabling PowerFlex 525 Safe-Torque-Off 239
Wiring 239
Verify Operation 240
PowerFlex 525 Safe-Torque-Off Operation 239
Connection Examples 241
PowerFlex 525 Certification for Safe-Torque-Off 245
The Safe-Torque-Off function covered in this chapter is specific to
PowerFlex 525 drives only.
The function is suitable for performing mechanical work on the drive system or
affected area of a machine only. It does not provide electrical safety.