Critical applications
If a safety function is not enabled in the inverter, then you can use the following critical
applications without any restrictions.
If a safety function is enabled in the inverter, then several applications can result in faults in
the safe actual value sensing. For active or enabled safety functions, faults and errors in the
safety-related actual value sensing initiate a stop response: Messages C01711, C30711 with
default values 1040 ff.
The stop response does not result in an unsafe drive state, but in a lower drive availability.
Critical application
Remedy
Motor data identification during
commissioning
Only commission the safety functions after the motor data identi‐
fication has been completed.
Setpoint change as step function
Set the ramp-function generator times to values > 0.5 s.
If you are using an inverter with position control, then you must
set the position controller and the travel profile so that there is
absolutely no overshoot in the speed/velocity characteristic.
Within 1 s, only one acceleration and one braking ramp are per‐
mitted. The cycle 0 → n
set
→ -n
set
→ 0 must be at least 2 s long.
Reversing the speed
Load change as step function
Do not use the safety functions.
Continuous operation at speeds <
5 % of the rated speed
Switching-on the inverter with the
motor rotating ("flying restart" func‐
tion)
Avoid using the "flying restart" function when a safety function is
active.
Temporarily deactivate the safety function until the "flying restart"
function has been successfully completed.
It is not permissible that you use the "flying restart" function if you
are using the SSM function. It is not possible to deactivate SSM
using a control signal.
Operating an inverter at the current
limit
Select and dimension the drive so that the inverter current limit
does not respond. After commissioning, check that the inverter
does not reach its current or torque limits – even at full load.
Braking a motor using the "DC brak‐
ing" or "Compound braking" func‐
tions
Avoid using the "DC braking" or "Compound braking" functions
when a safety function is active.
If you require one of the two braking functions, in the risk assess‐
ment you must check where it is permissible that you deactivate
the safety function while braking. If yes, then deactivate the safety
function until braking has been completed.
If you use the SSM function, then it is not permissible to use the
two braking functions. It is not possible to deactivate SSM using
a control signal.
Description
3.5 Restrictions when using safety functions
Safety Integrated - SINAMICS G110M, G120, G120C, G120D and SIMATIC ET 200pro FC-2
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Function Manual, 01/2017, FW V4.7 SP6, A5E34261271B AD
