Lenze EVF9333−xV - Manual (Page 297)

Configuration
Function blocks
Internal motor control with V/f characteristic control (MCTRL1)
8
8.2
8.2.6
l
8.2−35 EDSVF9333V EN 6.2−04/2012
The limitation of the output current is mainly used for the protection of the
controller and the stabilisation of the control.
When the maximum permissible motor load is exceeded, you can adapt the
max. output current of the controller accordingly.
Parameter setting
Code Function
C0022 Maximum current in motor mode
C0023 Maximum current in generator mode
If you select a motor (via C0086), the maximum current of which is clearly
lower than the output current of the controller, the maximum motor current
(C0022) is limited automatically to 200% of the rated motor current.
Mode of operation
In the V/f characteristic control mode, a PI controller (V
p
= C0075,
T
n
= C0076) prevents an excess of the max. permissible motor current by
reducing (motor overload) or increasing (generator overload) of the output
frequency.
The N controller is not active in the V/f characteristic control mode without
feedback.
Consequences
ƒ The motor cannot follow the speed setpoint.
ƒ MCTRL−IMAX is set to HIGH
ƒ When selecting the automatic switching frequency setting (C0018 = 0
or 6), the controller switches to a lower switching frequency so that a
disconnection is not required.
Limitation of the output
current