Control mode
U/f control or flux current control (FCC)
Encoderless vector control
Properties
● Typical settling time after a speed change:
100 ms … 200 ms
● Typical settling time after a load surge: 500 ms
6SHHG
/RDG
0RWRU
WRUTXH
W
W
W
PV
● The control mode is suitable to address the
following requirements:
– All motor power ratings
– Ramp-up time 0 → rated speed
(depending on the motor power rating):
1 s (0.1 kW) … 10 s (45 kW)
– Applications with increasing load torque
without load surges
● The control mode is insensitive with respect
to imprecise setting of the motor data
● Typical settling time after a speed change:
< 100 ms
● Typical settling time after a load surge: 200 ms
6SHHG
/RDG
0RWRU
WRUTXH
W
W
PV
● The control mode controls and limits the motor
torque
● Typically achieves a torque accuracy: ± 5 % for
15 % … 100 % of the rated speed
● We recommend the control mode for the
following applications:
– Motor power ratings > 11 kW
– For load surges 10 % … >100 % of the rated
motor torque
● The control mode is necessary for a ramp-up
time 0 → rated speed (dependent on the rated
motor power): < 1 s (0.1 kW) … < 10 s (132 kW).
Max. output fre‐
quency
550 Hz
240 Hz
Torque control
Without torque control
Speed control with lower-level torque control
Commissioning
● Contrary to vector control without encoder, a
speed controller does not have to be set.
Select the default setting for the interfaces of the inverter that is suitable for your application.
Default setting of the interfaces (Page 91)
6HWSRLQW
S
S
Q
Figure 5-9
Minimum and maximum motor speed
3
0$F3$U
3
0,1530
3
0$;530
Commissioning
5.4 Quick commissioning using the BOP-2 operator panel
SINAMICS G120C converter
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34263257B AF
131
