fitting of units is recommended. As a minimum, cabi-
nets should be enclosure IP 54.
Aggressive gases, such as sulphur, nitrogen and
chlorine compounds, together with high humidity and
temperature, facilitate possible chemical processes on
the components of the frequency converter. These
chemical processes quickly impact and damage the
electronics. In these areas, cabinet fitting with fresh-air
circulation in the cabinet is recommended, thereby en-
suring that aggressive gases are kept away from the
frequency converter.
NB!
Fitting of frequency converters in aggres-
sive environments increases the risk of
stoppages, in addition to considerably re-
ducing the service life of the unit.
Before the frequency converter is installed, it must be
checked whether there are liquids, particles or gases
in the air. This can be done by looking at existing in-
stallations in the same environment. Typical indicators
of harmful airborne liquids are water or oil on metal
parts or corrosion of metal parts. Too many dust par-
ticles are typically observed on top of installation cab-
inets and on existing electrical installations. Indicators
that there are aggressive gases in the air are copper
rails and cable ends that are black on existing electrical
installations.
142
MG.27.E2.02 - VLT is a registered Danfoss trademark
