Special Conditions; Derating For Ambient Temperature And Switching Frequency; Derating For Low Air Pressure; Options For Vlt Hvac Basic Drive Fc101 - Danfoss VLT FC 101 Quick Manual

Quick Guide VLT HVAC Basic Drive Quick Guide
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1.8 Special Conditions

1.8.1 Derating for Ambient Temperature
and Switching Frequency
The ambient temperature measured over 24 hours should
be at least 41° F [5°C] lower than the max. ambient
temperature. If the Adjustable frequency drive is operated
at high ambient temperature, the continuous output
current should be decreased. For derating curve, please
see Design Guide MG18C3YY.

1.8.2 Derating for Low Air Pressure

The cooling capability of air is decreased at low air
pressure. For altitudes above 6,600 feet [2,000 m], please
contact Danfoss regarding PELV. Below 3,281 ft [1,000 m]
altitude no de-rating is necessary, but above 3,281 ft [1,000
m] the ambient temperature or the maximum output
current should be decreased. Decrease the output by 1%
per 328 ft [100 m] altitude above 3,281 ft [1,000 m] or
reduce the max. ambient temperature by 1° per 656 ft
[200 m].

1.9 Options for VLT HVAC Basic Drive FC101

For options, please see the Design Guide MG18C3YY.
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MG18A322 - VLT is a registered Danfoss trademark 1-45