Lenze 8400 motec - Manual (Page 95)

Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05 95
5 Motor control (MCTRL)
5.4 Defining current and speed limits
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
How to adapt the peak current limitation:
V/f characteristic control (VFCplus):
• Reduce the slip compensation with C00021 .
Sensorless vector control (SLVC):
• Reduce the slip compensation with C00021 .
• Reduce the limitation of the torque in motor mode via the nTorqueMotLimit_a process
signal and the limitation of the torque in generator mode via the nTorqueGenLimit_a
process signal.

Note!
Highly dynamic applications
(High accelerations or short and big overloads)
The overcurrent disconnection may respond (fault message OC1) if the setting of the
maximum current in motor mode in C00022 approximately corresponds to the
maximum permissible value of the respective inverter.
Remedies:
• Increasing the acceleration and deceleration time ( C00012 und C00013 )
• Reduction of the maximum current in motor mode (C00022 )
• Reduction of the maximum current in generator mode ( C00023 )
• Adaptation of the indirect peak current limitation (procedure depends on the selected
motor control mode, see below)
• Reduction of the reset time of the current limiting controller ( C00074 )
Influencing the torque in motor/generator mode
The torque in motor and generator mode can be limited via the nTorqueMotLimit_a and
nTorqueGenLimit_a process signal inputs.
• If V/f characteristic control (VFCplus) is selected, limitation is indirectly performed via
a so-called I
max
controller.
• If sensorless vector control (SLVC) is selected, limitation has a direct effect on the
torque-producing current component.