Rockwell Automation 2099-BMxx-S Kinetix Safe Torque-off Feature Safety Reference Manual - Manual (Page 13)

Rockwell Automation Publication GMC-RM002F-EN-P - June 2013 13
Safety Concept and Troubleshooting Chapter 1
Understanding the Safe Torque-off Condition vs Drive Fault
When both inputs de-energize within 100 ms, a fault does not occur (E49 is not
displayed), however, a safe torque-off state is entered within the 25 ms response
time. The safe torque-off condition occurs through normal drive operation.
A mismatch occurs when one input is de-energized while the other input is
energized after 100 ms. This causes the E49 error code to display and the drive
begins a shutdown sequence. Causes for a mismatch include:
• wiring anomalies at the Safe Torque-off (STO) connector, pins STO-5 and
STO-7, or the external monitoring relay.
• input anomalies associated with the Safe Torque-off (STO) connector,
pins STO-5 and STO-7.
• sequencing errors in the program.
• EMI interference.
To determine if you have a safe torque-off fault or condition, you must examine
the Axis_Servo_Drive status bit in RSLogix 5000 software.
• If bit status is 0, then no safe torque-off condition or fault exists.
• If bit status is 1, then a safe torque-off condition or fault does exist.
Figure 1 - RSLogix 5000 Software, Version 15 Safe Torque-off Status Bit
In the RSLogix 5000, version 15 example, the
axis.DriveStatus.14 bit is set to 0,
indicating the drive is not in Safe Torque-off mode. No safe torque-off condition
or fault exists.
Figure 2 - RSLogix 5000 Software, Version 16 (or later) Safe Torque-off Status Bit
In the RSLogix 5000, version 16 example, the
axis.SafeOffModeActiveStatus bit
is set to 0, indicating the drive is not in Safe Torque-off mode. No safe torque-off
condition or fault exists.