Lenze i750 - Safe Operating Stop (SOS)

Error behaviour
An error message and an error stop are triggered if:
•
the curr
ent speed exceeds the stopping me of the speed ramp parameterised.
•
the current speed exceeds the parameterised speed ramp before the tolerance window is
reached.
The power supply for g
eneraong the rotang eld is safely interrupted (STO). The motor
cannot generate torques and movements of the drive.
Safe operang stop (SOS)
In the safe operaonal stop, the drive is not switched to torque-free operaon. All control
funcons are maintained. The reached posion remains acve.
DANGER!
Uncontrolled r
otaon of the motor possible if no safety rated encoder system is used.
Possible consequence: Death or severe injuries
▶
Use a safety rated encoder system to use this funcon.
Precondions
The drive is brought to s
tandsll via the applicaon.
Funconal descripon
n
t
0
SOS
STO
0x289F:001
Fig. 16: SOS funcon
SOS is acv
ated if the motor speed is lower than the tolerance window parameterized in
0x287B:001. In SOS state, relave posion changes are added and stored in 0x289F:003. The
value in 0x289F:003 is connuously compared with the permissible value in 0x289F:001. If in
SOS state the posion leaves the safely monitored tolerance window, an error message is
generated and STO is acvated.
When the SOS state is le, the maximum relave posion change is displayed in 0x289F:003.
The parameter 0x289F:002 denes the restart behavior aer SOS has been deacvated.
When the SOS state is requested again, the sum of the last posion changes is reset to zero in
0x289F:003.
Example:
The "SS2 acve" state is interrupted by a STO request. If the STO request is reset, the
transion to the SOS state occurs. The posion deviaon is reset to p = 0.
Acvaon of the funcon
•
Via the sa
fety bus. 4Safe network interfaces ^ 149
•
Via the funcon Safe stop 2 (SS2) ^ 123
Behavior of the funcon in the e
vent of an error
In the "Safe operaonal stop (SOS)" nal state, an error message is triggered if the posion
leaves the set tolerance window p = 0. 0x289F:001
Funconal safety
Safety funcons
Safe operang stop (SOS)
126