VLT
®
4000 VT
■
Special conditions
■
Aggressive environments
In common with all electronic equipment, a VLT
AFD contains a large number of mechanical and
electronic components, all of which are vulnerable
to environmental effects to some extent.
The VLT AFD should not therefore be
installed in environments with airborn liquids,
particles or gasses capable of affecting and
damaging the elec-tronic components. Failure to take
the necessary protective measures increases the risk of
stoppages, thus reducing the life of the VLT AFD.
Liquids can be carried through the air and condense
in the VLT AFD. In addition to this, liquids may cause
corrosion of components and metal parts.
Steam, oil and salt water may cause corrosion
of components and metal parts. In such
environments, equipment with enclosure rating
NEMA 12 is recommended.
Airborne particles such as dust particles may cause
mechanical, electrical or thermal failure in the VLT AFD.
A typical indicator of excessive levels of airborne
particles is dust particles around the VLT AFD
fan. In very dusty environments, equipment with
enclosure rating NEMA 12 or a cabinet for Chassis/
NEMA 1 equipment is recommended.
In environments with high temperatures and humidity,
corrosive gases such as sulphur, nitrogen and chlorine
compounds will cause chemical processes on the VLT
AFD components. Such chemical reactions will rapidly
affect and damage the electronic components.
In such environments, it is recommended
that equipment is mounted in a cabinet with
fresh air ventila-tion, keeping aggressive gases
away from the VLT AFD.
NOTE
Mounting VLT AFD in aggressive environments
will increase the risk of stoppages
and furthermore considerably reduce
the life of the drive.
Before the installation of the VLT AFD, the ambient
air should be checked for liquids, particles and
gasses. This may be done by observing existing
installations in this environment. Typical indicators
of harmful airborne liquids are water or oil on metal
parts, or corrosion of metal parts.
Excessive dust particle levels are often found on
installa-tion cabinets and existing electrical installations.
One indicator of aggressive airborn gasses is blackening
of copper rails and cable ends on existing installations.
MG.40.A7.22 - VLT is a registered Danfoss trademark
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