Siemens SIMOTICS M-1PH1, Equipment Manual

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Configuration
7.2 Specifying the duty cycle
1PH1 main motors
Equipment Manual, 09/2021, A5E51077676A-AA
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7.2 Specifying the duty cycle
Duty cycles with a constant ON period
For duty cycles with a constant ON period, there are specific requirements for the torque characteristic
curve as a function of the speed, for example, M = constant, M ~ n
2
, M ~ n, or P = constant.
The figure below shows the S1 duty cycle for continuous operation.
These drives typically operate at a specific operating point and are dimensioned for a base
load. The base load torque must lie below the S1 characteristic curve. An overload rating is
provided for transient overloads (for example, during acceleration). The overload current
must be calculated relative to the required overload torque. The peak torque must lie below
the voltage limiting characteristic curve.
Duty cycles with a varying ON period
Besides continuous duty cycles (S1), standard intermittent duty cycles (S6) are defined for
duty cycles with a varying ON period. This is a mode of operation consisting of a series of
similar cycles, with each one comprising one time period with a constant load and one idle
time period. There is no pause.
The figure below shows the S6 duty cycle for continuous duty with an intermittent load.
The following fixed variables (overload factors) are usually applied to the relative ON period:
• S6-40%
• S6-25%
• S6-15%