Siemens SIMOTICS T-1FW68, Configuration Manual

Page: 91 / 194

Configuring
5.1 Configuring workflow
1FW68 radial segment motors
Configuration Manual, 08/2021, A5E51132930B AA
89
Note
Depending on the application, e.g. for a horizontal axis, when determining the required
torque, the gravitational torque M
g
must also be taken into account.
M
m
= M
a
+ M
b
+ M
r
+ M
g
The gravitational torque reaches its highest level for
M
g
= m • g • r
m: moved mass
g: acceleration due to gravity
r: radius of the circular path
In addition to the peak torque M
mMAX
, the required rms torque of the duty cycle M
eff
of the
motor is also a crucial factor when dimensioning the motor. The rms torque M
eff
of the
duty cycle mainly responsible for the temperature rise in the motor can be derived from
the motor torque-time diagram by means of quadratic averaging (root mean square) and
must not exceed the rated torque M
N
.
If the individual torques are constant in each section, the integral can be simplified to
create a totals formula (see also the following diagram).
Figure 5-4 Motor torque-time diagram