Special Conditions - Danfoss VLT AQUA Design Manual

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VLT AQUA Drive Design Guide 3. VLT AQUA Selection

3.5. Special Conditions

3.5.1. 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.
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3.5.2. Derating for Ambient Temperature
The average temperature (T ) measured over 24 hours must be at least 5 °C lower than the maximum allowed ambient temperature (T ).
AMB, AVG AMB,MAX
If the frequency converter is operated at high ambient temperatures, the continuous output current should be decreased.
The derating depends on the switching pattern, which can be set to 60 AVM or SFAVM in parameter 14-00.
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MG.20.N3.02 - VLT is a registered Danfoss trademark