Purpose Of Derating; Derating For Ambient Temperature; Automatic Adaptations To Ensure Performance; Special Conditions - Danfoss vlt FC 102 Operating Instructions Manual

8. Specifications

8.2. Special Conditions

8.2.1. 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.

8.2.2. Derating for Ambient Temperature

With a typical full load current of EFF 2 motors, full output shaft power can be maintained up to 50 °C.
For more specific data and/or derating information for other motors or conditions, please contact Danfoss.

8.2.3. Automatic adaptations to ensure performance

The frequency converter constantly checks for critical levels of internal temperature, load current, high voltage on the intermediate circuit and low motor
speeds. As a response to a critical level, the frequency converter can adjust the switching frequency and/ or change the switching pattern in order to
ensure the performance of the frequency converter. The capability to automatically reduce the output current extends the acceptable operating conditions
even further.
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MG.11.A6.02 - VLT ® is a registered Danfoss trademark
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VLT HVAC Drive Operating Instructions