Siemens Sinamics S120 Function Manual page 85

● This also applies to positioning operation; it may be necessary that the position control
settings and traversing profiles must be adapted so that no overshoots occur in the speed
characteristic (e.g. reduce the dynamic response, use flatter braking ramps).
● Flying restart
A flying restart should not be performed in operation with the Safety Integrated Functions
active.
Not e
If you must use this function, then before the flying restart, you can deactivate the Safety
Integrated Functions, and then reactivate them again after the flying restart has been
completed.
In t his case, t he user must check as t o whether it is permissible t hat t he safety functions
are deactivated during t he f lying restart.
It is only permissible t o activate and deactivate S afety Integrated Functions using fail-safe
s ignals.
● DC brake
When using this function, DC current is impressed to brake the drive: This can result in a
fault of the encoderless safe actual value acquisition and a consequent stop response.
Not e
If you must use this function, then before braking, you can deactivate the Safety
Integrated Functions, and then reactivate them again after braking has been completed.
In t his case, t he user must check as t o whether it is permissible t hat t he safety functions
are deactivated during braking.
It is only permissible t o activate and deactivate S afety Integrated Functions using fail-safe
s ignals.
Recommendations for stable operation with active Extended Functions without encoder
The following preconditions must be fulfilled to avoid fault messages from the safe actual
value sensing without encoder:
● The motor and the power unit are adequately dimensioned for this application.
● Motor and power unit should fulfill the following condition: The ratio between the rated
power unit current (r0207[0]) and rated motor current (p0305) should be less than 5.
● Before commissioning the safety functions, we recommend that the motor data are
identified at standstill and a rotating measurement is carried out.
● For the basic commissioning, i.e. before the safety commissioning, the closed-loop
control should be optimally set. The following effects should be avoided:
- speed overshoots
- current peaks and/or discontinuous/unsteady current actual value over time
- voltage peaks and/or discontinuous/unsteady voltage actual value over time
- the lowest possible amount of noise in the current and voltage
Safety Integrated
Function Manual, (FHS), 07/2016, 6SL3097-4AR00-0BP6
Description of Safety Integrated functions
4.2 Safety Integrated Extended Functions
85