Siemens TV Converter Box 611 User Manual
Configuring the motor
5.2 Example(s)
The accelerating torque M
a
can now be corrected as follows:
M
a
= (5.1 kgm
2
+ 0.0465 kgm
2
) • 52.36 rad/s
2
= 269 Nm
As a result, the total required motor torque M
m
= M
r
+ M
a
increases to 369 Nm.
Moment of inertia of motor 1FW6130-0PA05-1JC2: J = 0.0637 kgm
2
The accelerating torque M
a
can now be corrected as follows:
M
a
= (5.1 kgm
2
+ 0.0637 kgm
2
) • 52.36 rad/s
2
= 270 Nm
As a result, the total required motor torque M
m
= M
r
+ M
a
increases to 370 Nm.
Evaluation
Both motors are suitable for this positioning task. The installation requirements govern which
motor is better suited. During positioning, the motor generates a torque that far exceeds the
rated torque M
N
and the resulting power loss is much greater than the permissible
continuous power loss. Provided that positioning only takes a short time and the winding
temperature remains below the shutdown limit, this high load is permissible. See "Periodic
duty S3".
Periodic duty cycle (S3 mode)
The motor can repeat a drive operation (e.g. positioning) where M is occasionally > M
N
for as
long as necessary provided that sufficient zero-current pauses for the windings exist
between the load phases. See also "Periodic duty S3".
The "duty cycle" comprises the load phase and the zero-current (cooling) phase. The cooling
The "duty cycle" comprises the load phase and the zero-current (cooling) phase. The cooling
phases are crucial here: during the pauses, the effective torque of the duty cycle is reduced
to the value of the rated torque M
N
of the motor.
If the future duty cycle is either not known or cannot be estimated, the motor can only be
selected on the basis of the required maximum speed and peak torque. This is why the
maximum permissible continuous torque is also defined for the duty cycle. This results in a
very short cooling phase, the length of which must not be undershot.
As an example, let us take a highly simplified duty cycle comprising three time periods of
As an example, let us take a highly simplified duty cycle comprising three time periods of
lengths Δt
1
, Δt
2
, and Δt
3
. The following torques are generated in these periods: M
1
, M
2
, M
3
.
Each of these torques can be any value between + M
MAX
and – M
MAX
. The effective torque
M
eff
of this duty cycle (in Nm) can be calculated using the following formula:
0
HII
The cycle duration here (Δt
1
+ Δt
2
+ Δt
3
) should not exceed 10% of the thermal time constant
t
TH
.
The duty cycle is permissible provided that M
eff
is ≤ M
N
.
1FW6 Built-in torque motors
Configuration Manual, 05/2009, 6SN1197-0AD00-0BP7
Configuration Manual, 05/2009, 6SN1197-0AD00-0BP7
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