Lenze 8400 StateLine - Manual (Page 124)

5 Motor control (MCTRL)
5.3 Defining current and speed limits
124
Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14
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Current limitation in motor and generator mode
In the various motor control modes, the controller is provided with functions which determine the
dynamic behaviour under load and counteract exceedance of the maximum current in motor or
generator mode.
The current limits must be selected depending on
• the permissible maximum current of the motor  recommendation: I(Mot)
N
< 1.5 ... 2.0
• the permissible maximum current of the inverter
• the torque in motor/generator mode required for the application
Parameter Info Lenze setting
Value Unit
C00022 Imax in motor mode 47.00 A
C00023 Imax in generator mode
• 100 % ≡ Imax in motor mode ( C00022 )
100 %

Note!
Highly dynamic applications
(that have e.g. too short acceleration/deceleration times or excessively changing loads)
The overcurrent disconnection may respond (fault message oC1 or oC11) if the setting of
the maximum current in motor mode in C00022 approximately corresponds to the
maximum permissible value of the respective inverter.
Remedies:
• Increase of the acceleration and deceleration ramp times
• 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 ( C00074/1 )
Influencing the torque in motor/generator mode
The torque in motor and generator mode can be limited via the nTorqueMotLim and
nTorqueGenLim 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) and sensorless control for synchronous motors
(SLPSM) is selected, limitation has a direct effect on the torque-producing current
component.
If keypad control is selected, the nTorqueMotLim and nTorqueGenLim process signals can
be parameterised via C00728/1...2 .