
Advanced commissioning
7.11 Motor control
SIMATIC ET 200pro FC-2 converter
Operating Instructions, 04/2018, FW V4.7 SP10, A5E34257324B AF
163
When using the moment of inertia estimator, we recommend that you also activate the
friction characteristic.
Friction characteristic (Page 159)
How does the inverter calculate the load torque?
Figure 7-34 Calculating the load torque
At low speeds, the inverter calculates the load torque M
L
from the actual motor torque.
The calculation takes place under the following conditions:
●
Speed
≥
p1226
●
Acceleration setpoint < 8 1/s
2
(
≙
speed change 480 rpm per s)
●
Acceleration × moment of inertia (r1493) < 0.9 × p1560
How does the inverter calculate the moment of inertia?
Figure 7-35 Calculating the moment of inertia