Danfoss FC322 Series, Инструкция по эксплуатации

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10.1 Special Conditions
10.2.1 Purpose of Derating
Derating must be taken into account when using the frequency converter at low air pressure (heights), at low speeds, with long motor cables, cables
with a large cross section or at high ambient temperature. The required action is described in this section.
10.2.2 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
AMB
) or max. output current (I
out
) should be derated in
accordance with the shown diagram.
Illustration 10.1: Derating of output current versus altitude at T
AMB, MAX
for frame sizes A, B and C. At altitudes above 2 km, please contact
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
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.
Derating of output current versus altitude at T
AMB, MAX
for frame sizes D, E and F.
Automation VT Drive FC322
Instruction Manual 10 Specifications
MG.20.U1.22
179
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