Air Circulation/Cooling; Condensation And Dripping Water; Vibration And Mechanical Resonances - Danfoss VLT Inverter Scroll CDS 801 Operating Instructions Manual

Mechanical Installation

2.3 Air Circulation/Cooling

The drive must be installed in a way that allows for free
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airflow. However short circuiting the airflow (warm air re-
entering the drive's cooling fan) must be avoided (see
Illustration 2.8). A clearance of 5 inches (12.7 cm) must be
observed in both ends of the drive chassis. Install the drive
in a location where coldest possible air can be drawn into
the drive, i.e. from the bottom part of an outdoor unit.
Counter flow (static pressure) must not restrict the
operation of the internal cooling fan of the drive.
Illustration 2.8 Wrong Drive Airflow

2.4 Condensation and Dripping Water

The printed circuit board assembly of the drive is
conformally coated and thus sufficiently protected against
condensation during off time. Nevertheless, the drive
should not be exposed to dripping water (rain) or
condensing water slung around by the condenser fan. In
outdoor units, it is recommendable to install the drive in a
rain proof compartment.
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VLT Inverter Scroll CDS 801 Operating Instructions

2.5 Vibration and Mechanical Resonances

The mechanical structure (sheet metal) carrying the drive
must be designed to withstand vibration and consequently
resonances induced by the compressor or condenser fan.
See vibration specification for the drive further down this
document.
Also refer to 6.3.5.8 Frequency Cancelation explaining the
possibility to program bypass frequencies in the drive to
avoid mechanical resonances of the structure.
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MG10V402 - VLT is a registered Danfoss trademark