Siemens SIMOTICS S-1FK2 - Page 73

The e󹪜ective torque is obtained as follows:
T
0RWL
L
0RWHII
2
=
•
M
M
t
Δ
∑
The average motor speed is calculated as follows:
=
+
2
•

n
n n
t
0RWPLWWHO
0RWL$0RWL(
L
T
J
M
Motor moment of inertia
J
G
Gearbox moment of inertia
J
load
Load moment of inertia
n
load
Load speed
i Gear ratio
η
G
Gearbox e󹪟ciency
M
load
Load torque
M
R
Frictional torque
T Cycle time
A; E Initial value, 󹪝nal value in time slice Δt
i
t
e
ON duration
∆t
i
Time interval
The e󹪜ective torque M
e󹪜
must lie below the S1 characteristic.
The maximum torque M
max
is produced during the acceleration operation. M
max
must lie below
the voltage limiting characteristic curve. In summary, the motor is con󹪝gured as follows:
7RUTXHLQ1P
0RWRUVSHHGLQUPLQ
6
0BPD[
0BPD[IURPWUDYHOFXUYH
0BUPV
QBDYHUDJH









M_max Curve of the maximum torque S1 S1 characteristic = M
0
M_e󹪜 E󹪜ective torque ● Points from the traversing pro󹪝le
n_mean Mean speed
Figure 5-5 Motor selection for duty cycle
You have de󹪝ned the characteristic motor values corresponding to the duty cycle.
Con󹪝guration
5.2 Con󹪝guring procedure
1FK2 Synchronous Motors for SINAMICS S120
Con󹪝guration Manual, 02/2022, A5E46927724B AD 71