ABB FSO-12, User Manual

Page: 71 / 388

Safety functions 71
Step Description
1 The SS1 request is received (for example, from the I/O). The FSO starts a counter for
time B.
2 After time E has elapsed, the drive starts to ramp down the motor speed. SAR1
parameter
200.112 defines the deceleration ramp.
Note: If parameter 200.112 has value 0 , the drive (parameter 23.23 ) defines the ramp.
3 The motor speed goes below the SBC speed limit (A), the FSO activates SBC function.
The FSO starts counters for times C and D.
Note : You can define an extra delay (parameter SS1.15 , not shown in the figure) before
the FSO activates the SBC function. This affects also the STO activation (step 4).
3b If the drive has not ramped down fast enough when time B has elapsed, the FSO
activates the STO function. See section
Safe torque off (STO) on page 55 for more
information on how to configure the STO function.
4 After time C has elapsed, the FSO activates the drive STO function.
5 The SS1 request is removed.
6 After time D has elapsed, the FSO defines the motor as stopped, the SS1 completed
indication goes on and the acknowledgement becomes allowed as soon as the SS1
request has been removed (step 5).
7 After the acknowledgement, the SS1, STO and SBC functions are deactivated and the
control is given back to the drive, which is allowed to modulate again. The indications
go off.