Hitachi L300P - Manual (Page 30)

L300P Inverter
Getti
n
g Star
ted
1–11
Derating Curves The maximum available inverter current output is limited by the carrier frequency and ambient
temperature. The carrier frequency is the inverter’s internal power switching frequency, settable
from 0.5 kHz to 12 kHz, or 0.5 kHz to 8 kHz for higher horsepower models. Choosing a higher
carrier frequency tends to decrease audible noise, but it also increases the internal heating of the
inverter, thus decreasing (derating) the maximum current output capability. Ambient tempera-
ture is the temperature just outside the inverter housing—such as inside the control cabinet
where the inverter is mounted. A higher ambient temperature decreases (derates) the inverter’s
maximum current output capacity.
Use the following derating curves to help determine the optimal carrier frequency setting for
your inverter, and to find the output current derating. Be sure to use the proper curve for your
particular L300P inverter model number.
L300P 1.5 to 22 kW 200V class
2 4 6 8 10 12 0.5
65%
70%
75%
80%
85%
90%
95%
100%
Carrier Frequency (kHz)
% of Drive’
s
Rate
d Am
ps
015L, 022L,
037L, 055L,
075L, 110L,
150L, 185L
60%
55%
110L
150L
185L
Legend: Output current at 40
°C ambient
Output current at 50
°C ambient
220L
220L