Lenze E82xVxxxKxxxxx - Manual (Page 284)

Function library
Limit value setting
Current limits
10
l
284 EDS82EV903 EN 3.0
10.5.2 Current limits
Description
The controllers are equipped with a current−limit control which determines the dynamic
response under load. The measured load is compared with the limit values set under C0022
for motor load and C0023 for generator load. If the current limit is exceeded, the controller
will change its dynamic behaviour:
Controller performance when a limit value is reached
Motor overload during acceleration:
The controller prolongs the acceleration ramp.
Generator overload during deceleration:
The controller prolongs the deceleration ramp.
With increasing load and constant speed:
ƒ When the current limit of the motor mode is reached:
– The controller reduces the output frequency to 0 Hz.
– The controller cancels the change of the output frequency if the load falls below
the limit value.
ƒ When the current limit in the generator mode is reached:
– The controller increases the output frequency up to the maximum frequency
(C0011).
– The controller cancels the change of the output frequency if the load falls below
the limit value.
ƒ If suddenly a load is applied to the motor shaft (e.g. drive is blocked), the overcurrent
switch−off can be activated (error message OCX).
Codes for parameter setting
Code Possible settings IMPORTANT
No. Name Lenze Selection
C0022 I
max
limit in
motor mode
150 30 {1 %} 150 Only 8200 vector 15 ... 90 kW):
If C0022 = 150 %, 180 % I
rated
are
available for max. 3 s after
controller enable.
^ 284
C0023 I
max
limit in
generator
mode
150 30 {1 %} 150 C0023 = 30 %: function inactive if
C0014 = 2, 3
^ 284
Adjustment
ƒ Set the acceleration and deceleration times so that the drive can follow the speed
profile without reaching I
max
of the controller.
ƒ C0022 and C0023 refer to the rated output current at a switching frequency of 8
kHz.
ƒ When operating with a switching frequency of 16 kHz you must adapt C0022 and
C0023 to the permissible output currents (derating).
ƒ Correct current control for operation in generator mode is only possible with
external brake resistor.