Danfoss VLT HVAC Design Manual page 91

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VLT HVAC Drive Design Guide
Switching frequency
When frequency converters are used together with Sine-wave filters to reduce the acoustic noise from a motor, the switching frequency must be set
according to the Sine-wave filter instruction in par. 14-01
Aluminium conductors
Aluminium conductors are not recommended. Terminals can accept aluminium conductors but the conductor surface has to be clean and the oxidation
must be removed and sealed by neutral acid free Vaseline grease before the conductor is connected.
Furthermore, the terminal screw must be retightened after two days due to the softness of the aluminium. It is crucial to keep the connection a gas tight
joint, otherwise the aluminium surface will oxidize again.
5.2.5 Enclosure knock-outs
Illustration 5.9: Cable entry holes for enclosure A5. The suggested use of the holes are purely recommendations and other solutions are
possible.
Illustration 5.10: Cable entry holes for enclosure B1. The suggested use of the holes are purely recommendations and other solutions are
possible.
Illustration 5.11: Cable entry holes for enclosure B1. The suggested use of the holes are purely recommendations and other solutions are
possible.
Switching Frequency .
MG.11.B9.02 - VLT ® is a registered Danfoss trademark
5 How to Install
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