ABB ACS880-07 User Manual page 25

3. a) The motor speed goes below the zero speed limit (B). The FSO module activates the
drive STO function. The emergency stop indication lamp comes on.
Note: You can set an additional delay for the STO activation (parameter SS1.15 SS1-r
ramp zero speed delay for STO).
4. a) Time A has elapsed. The STO function is already active. In this case, this time has
no effect.
5. a) The user releases the emergency stop button.
6. a) The user pushes the reset button (this resets the emergency stop circuit and
acknowledges the STO function).
7. a) The FSO module deactivates the STO function in the drive. The emergency stop
indication lamp goes off. The drive is ready for a restart.
Case B: The motor speed does not reach the zero speed limit within the user-defined time
Time A has elapsed from the emergency stop command (step 1) but the motor speed still
exceeds the zero speed limit.
Motor speed
SS1.14
A
C
B
1 2
A SS1-t monitoring time: When time A has elapsed from the start of the timer (step 1), the FSO
module activates FSO and drive STO functions (case B). In case A, the FSO module has
already activated the STO function. This is a user-defined value (parameter SS1.14 SS1-t
delay for STO).
B Zero speed limit: Speed limit for activating the drive STO function. This is a user-defined value
(parameter FSOGEN.52 Zero speed with encoder).
C Safety function response time.
1. The user pushes the emergency stop button (this activates the SS1 function of the FSO
module). The FSO module starts a timer for delay A.
2. The drive starts to decelerate the motor along the user-defined stop ramp (SAR1
parameter 200.112 SAR1 ramp time to zero).
3b
4b
Option description 25
6b 7b
5b
Time
E-stop button
(SS1 request)
Drive STO
status
Reset button
Indication lamp