9.2 Derating for Altitude and Ambient
Temperature
The cooling capability of air is decreased at lower air
pressure.
Below 1000 m altitude no derating is necessary, but above
1000 m the ambient temperature (T
AMB
) or maximum
output current (I
out
) should be derated in accordance with
Illustration 9.1
.
An alternative is to lower the ambient temperature at high
altitudes and thereby ensure 100% output current at high
altitudes. As an example of how to read the graph, the
situation at 2000 m is elaborated. At a temperature of 45
°
C (T
AMB, MAX
- 3.3 K), 91% of the rated output current is
available. At a temperature of 41.7
°
C, 100% of the rated
output current is available.
80
0
500
100
95
90
85
1000
1500
2000
2500
3000
Altitude (meters above sea level)*
130BB008.10
I
OUT
(%)
Illustration 9.1 Altitude Derating
110
100
90
80
70
60
50
40
30
20
10
0
0
5
10
15
20
25
30
35
40
45
50
55
Tamb (Max) Deg C
Iout (%)
130BD937.10
Illustration 9.2 Input/Output vs. Maximum Ambient
Temperature
9.3 Acoustic Noise
AAF190
AAF250, AAF310, and AAF400
DUT idle running (60 Hz) with no load with
fans on
73
66.5
DUT running (60 Hz) with 100% load
78.7
69
Table 9.2 Acoustic Noise
Specifications
Operating Instructions
84
Danfoss A/S © 09/2014 All rights reserved.
MG90V302
9
9
