Siemens SIMODRIVE 6SN11 Series Planning Manual page 77

09.00
Planning
Selection
A differentiation must be made between three applications when selecting a
suitable 1PH motor:
Case 1: The motor essentially operates in continuous operation.
Case 2: The drive is dimensioned according to the periodic load duty cycle.
case 3:
Case 1
A motor should be selected, whose S1 output is the same or greater than the
required drive output.
Using speed–power diagrams, it should be checked as to whether the output is
available over the required speed range. If required, a larger motor must be se-
lected.
Case 2
The drive is dimensioned according to the load duty cycle.
It is assumed that the speeds are below the rated speed during the load duty
cycle.
If the torques during the load duty cycle are not known, but only the power, then
the power can be converted into a torque using the following equation:
M = P < 9550/n,
The torque, which the motor must provide, comprises the friction torque
M
que M
M = M
 Siemens AG 2000 All rights reserved
SIMODRIVE Planning Guide Motors (PJM) – 11.00 Edition
General Information on AC Induction Motors
A high field–weakening range is required.
M in Nm, P in kW, n in RPM
, the load torque M
Friction Load
:
B
+ M + M
Friction Load B
6SN1197–0AA20
of the driven machine and the accelerating tor-
3 Planning
3
ALA
ALA/3-23