Siemens M200D Manual Do Utilizador
Functions
3.7 System monitoring
M200D AS-Interface Basic
Manual, 03/2009, A5E01668085-01
Manual, 03/2009, A5E01668085-01
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3.7.2
Asymmetry monitoring
Description
Three-phase induction motors respond to slight asymmetries in the supply voltage with a
higher asymmetric current consumption, which causes the temperature in the stator and
rotor windings to increase. In this case, the M200D motor starter protects the motor against
overload by shutting it down.
Note
When the motor is switched on, asymmetry evaluation is suppressed for approx. 0.5 s.
When the motor is switched on, asymmetry evaluation is suppressed for approx. 0.5 s.
Asymmetry limit value
The asymmetry limit is a percentage value by which the motor current is allowed to deviate
in each phase.
Asymmetry occurs when the difference between the lowest and highest phase current is
greater than the asymmetry limit value. The asymmetry limit for the M200D AS-i Basic is set
permanently to 30 %.
The reference value for the evaluation is the maximum phase current in one of the 3 phases.
The reference value for the evaluation is the maximum phase current in one of the 3 phases.
Response to asymmetry
If the asymmetry limit value is exceeded, the motor starter is shut down.