Lenze 8400 TopLine - Manual (Page 169)

Lenze · 8400 TopLine · Reference manual · DMS 6.0 EN · 06/2014 · TD05/TD14
169
5 Motor control (MCTRL)
5.4 V/f characteristic control (VFCplus)
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5.4.3.4 Optimising the stalling behaviour
Motor stalling due to a torque overload in the field weakening range is prevented in all
characteristic-based motor control types (VFCplus) by means of an inverter-internal stalling current
monitoring. In the field weakening range, hence at frequencies above the base frequency, it reduces
the maximum current to prevent the motor from stalling. The reduction depends on the current
field frequency, the base frequency, the DC-bus voltage and the maximum current ( C00022 ).
Generally it applies that a higher field frequency causes a stronger limitation of the maximum
current.
The behaviour in the field weakening range can be adapted via the override point of field weakening
( C00080 ). This parameter serves to shift the frequency-dependent maximum current characteristic:
• C00080 > 0 Hz:
• The maximum current characteristic is shifted by the entered frequency to higher field
frequencies.
• The maximally permissible current and the maximum torque increase in the field weakening
range.
• The risk of motor stalling increases.
• C00080 < 0 Hz:
• The maximum current characteristic is shifted by the entered frequency to lower field
frequencies.
• The maximally permissible current and the maximum torque are reduced in the field
weakening range.
• The risk of motor stalling is reduced.

Note!
We recommend to keep the Lenze setting (0 Hz).