Danfoss FC 300 Design Manual page 95

FC 300 Design Guide
Illustration 4.36: Derating of I
frame sizes E and F at 690 V, using 60º AVM in Normal tor-
que mode (110% over torque).
4.9.3 Derating for low air pressure
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
accordance with the shown diagram.
Illustration 4.38: Derating of output current versus altitude at T
Danfoss regarding PELV.
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 2 km is elaborated. At a temperature of 45° C (T
temperature of 41.7° C, 100% of the rated output current is available.
Derating of output current versus altitude at T
for different T for
out AMB, MAX
AMB, MAX
for frame sizes D, E and F.
AMB, MAX
MG.33.BC.02 - VLT ® is a registered Danfoss trademark
4 AutomationDrive FC 300 Selection
Illustration 4.37: Derating of I
frame sizes E and F at 690 V, using SFAVM in Normal torque
mode (110% over torque).
) or max. output current (I
AMB
for frame sizes A, B and C. At altitudes above 2 km, please contact
- 3.3 K), 91% of the rated output current is available. At a
AMB, MAX
for different T for
out AMB, MAX
) should be derated in
out
4
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