Behavior during sls monitoring – Rockwell Automation 21G PowerFlex 750-Series AC Drives Reference Manual User Manual
Page 87

Rockwell Automation Publication 750-RM001F-EN-P - February 2012
87
Safe Limited Speed (SLS) Modes
Chapter 7
Figure 23 - Timing Diagram for Safe Limited Speed (SLS) with Door Monitoring and Enabling
Switch Monitoring Mode
Behavior During SLS Monitoring
When Safe Limited Speed monitoring is active, door control logic is set to
Unlock if the ESM_In input is ON and the speed is detected at below the Safe
Speed Limit.
If the ESM_In input is ON, the door can be opened (DM_In transitions from
ON to OFF). However, if the ESM_In input transitions to OFF after the door
has been opened, an ESM Monitoring fault occurs. An ESM Monitoring fault is
a Stop Category fault, which initiates the configured P45 [Safe Stop Type].
If the DM_In input transitions from ON to OFF (door is opened), while the
ESM_In input is OFF, a Door Monitoring fault occurs. A Door Monitoring fault
is a Stop Category fault, which initiates the configured P45 [Safe Stop Type].
After the DM_In input turns OFF, it could turn back ON again if the door is
closed behind the operator but the ESM_In input is still monitored.
Table 15 - Safe Limited Speed Operation
SLS
Request
P55 [Safe Speed Limit]
Speed
Time
SLS Monitoring Delay:
P53
Safe Limited Speed
Active
SLS Fault
Acceptable Speed Range
SLS Request
Removed
Door is unlocked if the enabling switch is
in the middle position.
ATTENTION: While Safe Limited Speed Monitoring is active, the ESM_In input
is not monitored until the DM_In input is detected as OFF. Make sure that the
ESM_In input is not relied upon for safety until the DM_In input has
transitioned to OFF.
Safety Function Status
Drive In
Safe State
Drive Able
To Run (Ready)
Drive Able
To Run (Ready)
DM_In
Off
On
Off
ESM_In
Off
On or Off
On