Allen-Bradley PowerFlex 525 Application Technique page 15

Safety Function: Actuator Subsystems – Stop Category 1 via the PowerFlex 525 and PowerFlex 527 Drives with Safe Torque-off
This can be modeled as follows:
Output
Logic
Guardmaster
Guardmaster
PowerFlex
Multifunction-delay
Dual-input
527 Drive
Expansion Module
Safety Relay
Subsystem 3
Subsystem 2
Subsystem 1
The rest of the SISTEMA calculation in this document features a SensaGuard switch as an example of a typical safety input
device.
For instance, when the PowerFlex 525 drive is used, these are the SISTEMA calculations for the safety function, "Safety-
related stop function initiated by a safeguard:"
When the PowerFlex 525 drive is used in the safety function, "Prevention of an unexpected startup, " the SISTEMA
calculations are identical, because all of the same components are used.
Rockwell Automation Publication SAFETY-AT140A-EN-P - May 2015 15