Derating; Ambient Temperature Derating; Altitude Derating - ABB ACS880-37 Hardware Manual

Derating

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Ambient temperature derating

In the temperature range +40...50 °C (+104...122 °F), the rated output current is derated
by 1% for every added 1 °C (1.8 °F). The output current can be calculated by multiplying
the current given in the rating table by the derating factor (k):
k
1.00
0.90
0.80
+40 °C
+104 °F

Altitude derating

At altitudes from 1000 to 4000 m (3300 to 13123 ft) above sea level, the output current
derating is 1% for every 100 m (328 ft). If ambient temperature is below +40 °C (+104 °F),
the derating can be reduced by 1.5% for every 1 °C reduction in temperature. For a more
accurate derating, use the DriveSize PC tool. A few altitude derating curves are shown
below.
+50 °C T
+122 °F
Technical data 181