Siemens SINAMICS S120 Configuration Manual page 43

Calculating the new limit torque with the new limiting characteristic
M
The value M
speed).
Figure 4-3
P1
P2
P3
P4
Synchronous Motors 1FK7
Configuration Manual, (PFK7S), Edition 12.2006, 6SN1197-0AD16-0BP1
V V
-
= •
M
V V
-
is read-off from the limiting characteristic curve for U
limit
Offset of voltage limiting characteristic from U
The voltage limiting characteristic curve specified for U
n [RPM].
1
Offset from point where the voltage limiting characteristic curve intersects with the x axis from
n to n .
1 2
V
[ ]
n / 1 = n •
2 1
V
Read-off M on the voltage limiting characteristic curve specified for U
limit
Calculating M :
limit, new
V V
-
M = • M
V
V
-
M
limit, new
The offset voltage limiting characteristic curve is obtained with points P2 and P4.
4.2 Voltage limiting characteristics
(value at the rated
mot
to U
mot mot new
intersects with the x-axis (speed) at
mot
.
mot
Electrical data
43