Contents

Carrier Frequency Derating and Current Limitation
Current limitation level at low speeds
Varispeed L7 limits the output current at low frequencies. This current limitation does not change with the
carrier frequency selection. The current limitation in the low frequency is as follows.
150%
140% 200V Class 15kW
400V Class 30kW
130%
120%
110%
200V Class11kW
200V Class 3.7, 18, 30kW
400V Class 18, 22kW
200V Class 5.5kW
400V Class 3.7, 5.5, 7.5, 11, 55kW
0
200V Class 7.5, 22 , 37, 45, 55kW
400V Class 4.0, 15, 37, 45kW
1.5Hz
3Hz
4.5Hz
6Hz
Output
Frequency
IMPORTANT
Fig 5.31 Low frequency current limitation
• If the torque at low frequencies is too low, check whether the current runs into the limitation explained
above. If so, check the motor data settings (E2-) and the V/f pattern (E1-).
• If the current still runs into the limit it might be necessary to install a one size bigger inverter.
• When selecting an inverter please consider the low frequency current limit as described above and
select an inverter with an appropriate current margin.
5
5-3