ABB ACS880-01 - Altitude Derating

￭ Altitude derating
Altitude derating
At altitudes from 1000 to 4000 m (3300 to 13123 ft) above sea level, the 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.
1500 m
1000 m
+25 °C +30 °C
+77 °F +86 °F
+40 °C
+104 °F
+35 °C
+95 °F
+20 °C
+68 °F
3300 ft
4921 ft
2000 m
6562 ft
2500 m
8202 ft
3000 m
9842 ft
3500 m
11429 ft
4000 m
13123 ft
1.00
0.95
0.85
0.90
0.80
Derating factor 1.00
Derating factor 0.95
Derating factor 0.90
Derating factor 0.85
Derating factor 0.80
The altitude derating can be reduced if the temperature is below +40 °C, for example,
if the temperature is 30 °C, the derating factor is 1 - 1.5% · 10 = 0.85. You can reduce
the output current by 35% instead of 40% at 4000 meter above the sea level.
186 Technical data