11
Option description and instructions
3ADW0005Q964 E-Stop cat.1 without opening mains contactor en b
+Q964 Detailed timing chart
+Q964 Fault reaction function
Definition: A safety function requires a ‘fault reaction function’ that attempts to initiate a safe state if
the safety function's diagnostics detect a fault within the hardware/software that performs the safety
function.
The fault reaction function of the emergency stop safety relay [A61] trips if it detects a failure (short
circuit between signals, open circuits, redundancy fault when the emergency stop button is pushed) in
the safety circuit. The fault reaction function shifts the drive immediately into the safe state by
activating the Safe torque off (STO) function, switching on the drive emergency stop command, and
keeping it on until the detected fault has been repaired. The emergency stop indication lamp is on until
the fault has been repaired.
The emergency stop reset circuit must be open when the user releases the emergency stop button. The
emergency stop safety relay [A61] detects if the reset circuit is closed and the relay does not close. The
user must reset the safety relay, see section
Fault tracing
on page 17. For a detailed description of the
emergency stop safety relay [A61], see section
Hardware settings
on page 13.
The DCS880 STO function has its own internal fault diagnostics and fault reaction function.
