General Mechanical Conditions; Specification Of The Duty Cycle - Siemens SIMOTICS T-1FW6 Configuration Manual

Configuration
6.2 Configuring workflow
6.2.1

General mechanical conditions

Moment of inertia
The kinetic energy generated by a rotating body is directly proportional to its moment of inertia
J in kgm
across the entire volume of the body with respect to the rotary axes. The rotating mass comprises
the mass of the rotating mechanical structure (e.g. tool and holder) and the mass of the rotor.
Frictional torque
The frictional torque M
approximately calculated from a combination of the constant "adhesion component" M
"sliding friction component" M
Depending on the mechanical design, loads here generally include axial forces and clamping
forces between the bearing components.
Further procedure
The moment of inertia of a suitable motor type can be used here initially.
If it transpires that the discrepancy between the assumed and actual moment of inertia is too
great when further calculations are made, you then have to carry out a further iterative step
when selecting the motor. To calculate the frictional torque, use the relevant specifications
issued by the bearing manufacturer.
6.2.2

Specification of the duty cycle

Uninterrupted duty S1
With uninterrupted duty S1, the motor runs permanently with a constant load. The load period is
sufficient to achieve thermal equilibrium.
The rated data is of relevance when dimensioning the motor for uninterrupted duty.
NOTICE
Motor overload
An excessively high load can lead to shutdown, or if the temperature sensors are not correctly
evaluated, then the motor could be destroyed.
• Ensure that the load does not exceed the value I
• Ensure that the temperature sensors are correctly connected and evaluated.
96
. The moment of inertia takes into account the rotating mass and its spatial distribution
2
is in opposition to the direction in which the rotor rotates. It can be
r
RG
. Both components also depend on the bearing used and its load.
specified in the data sheets!
N
Configuration Manual, 09/2022, A5E52220645B AA
and
RH
1FW6 Built-in torque motors