Safe Torque Off Connector Data; Wire The Safe Torque Off Circuit; Safe Torque Off Wiring Requirements - Rockwell Automation Allen-Bradley PowerFlex 527 User Manual

Chapter 5 Hardwired Control of Safe Torque Off
Safe Torque Off Connector
Data
Wire the Safe Torque Off
Circuit
92
PowerFlex 527 terminals S1, S2, and 01 are used for hardwired control of safe torque off.
Terminals for Safe Torque Off (STO) Connection
Hardwired Safety Inputs
Safety Bypass Jumper
R1 R2 R5 R6
11 12 13 14 15 16 17
Safe Torque Off (STO) Connector Pinouts Control
STO Pin Signal
01 Digital Common
S1 Safety 1
S2 Safety 2
S+ Safety +24V
IMPORTANT Digital Common (terminal 01) is common for the digital inputs, the safety
inputs, and the encoder power supply (optional).
This section provides guidelines for wiring safe torque off connections to your PowerFlex 527 drive.
IMPORTANT The National Electrical Code and local electrical codes take precedence over
the values and methods provided.
IMPORTANT Pin S+ (Safety +24V) is used to disable the safe torque off function.
When wiring to the STO connector, use an external 24V supply for the
external safety device that triggers the safe torque off request. To avoid
jeopardizing system performance, do not use pin S+ as a power supply for
the external safety device.

Safe Torque Off Wiring Requirements

The safe torque off (STO) connection wire must be copper with 75 °C (167 °F) minimum rating.
IMPORTANT The National Electrical Code and local electrical codes take precedence over
the values and methods provided.
IMPORTANT Stranded wires must terminate with ferrules to help prevent short circuits,
per table D.7 of EN ISO 13849-2.
Safe Torque Off (STO) Terminal Wiring
(1)
Maximum Wire Size
2
1.3 mm (16 AWG)
(1) Maximum and minimum sizes that the terminal block will accept. These are not recommended wire sizes.
Rockwell Automation Publication 520-UM002E-EN-E - September 2024
S1 S2 S+
01 02 03 04 05 06 07
Description
The return for digital I/O. It is electrically isolated (along with the digital inputs
and encoder power) from the rest of the drive.
Safety input 1.
Safety input 2.
+24V supply for safety circuit. This is internally tied to the +24V DC source
(terminal 11).
(1)
Minimum Wire Size
2
0.13 mm (26 AWG)
Torque
0.71...0.86 N•m (6.2...7.6 lb•in)