8.7.2 Current limits
For the purpose of current limitaon, a maximum overload current can be set for the inverter.
If the current consumpon of the motor exceeds this current limit, the inverter changes its
dynamic behaviour, in order to counteract this exceedance.
Details
•
The maximum overload current of the inverter can be set in 0x6073 (P324.00).
•
Reference for the percentage seng of the maximum overload current is the rated motor
current set in 0x6075 (P323.00).
•
The actual motor current is displayed in 0x2D88 (P104.00).
If the change in the dynamic behaviour carried out by the inverter does not
result in exing the overcurrent state, the inverter outputs an error.
Load behaviour Impact
Overload during acceleraon in
motor mode
A longer me than is required for reaching the frequency setpoint is set.
Overload during deceleraon in
generator mode
A longer me than is required for reaching standsll is set.
Increasing load at constant fre-
quency
If the motor current limit value is reached:
•
The inverter reduces the eecve speed setpoint unl a stable working is set or an eecve speed setpoint
of 0 rpm is reached.
•
If the load is reduced, the inverter increases the eecve speed setpoint unl the setpoint speed is
reached or the load reaches the current limit value again.
When the generator current limit value is reached:
•
The inverter increases the eecve speed setpoint unl a stable working point is reached or up to the max-
imum permissible output frequency 0x2916 (P211.00).
•
If the load is reduced, the inverter reduces the eecve speed setpoint unl the setpoint speed is reached
or the load reaches the current limit value again.
If an abrupt load is building at the motor sha (e.g. drive is blocked), the overcurrent switch-o funcon may
respond.
Example: Overcurrent switch-o in case of a sudden load at the motor sha
0 Hz
30 Hz
10 Hz
20 Hz
40 Hz
50 Hz
60 Hz
t
0 Hz
30 Hz
10 Hz
20 Hz
40 Hz
50 Hz
60 Hz
t
0 %
100 %
t
0x6073
Motor load
Frequency setpoint selection
Output frequency
Motor control
Motor protecon
Current limits
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