General Information About Electrical Installation; High Voltage Warning; Earthing; Cables - Danfoss VLT 8000 AQUA series Operating Instructions Manual

General information about electrical installation

High voltage warning

The voltage of the frequency converter
is dangerous whenever the equipment is
connected to mains. Incorrect installation
of the motor or the frequency converter may cause
damage to the equipment, serious personal injury
or death. Consequently, the instructions in these
Operating Instructions, as well as national and
local safety regulations, must be complied with.
Touching the electrical parts may be fatal - even
after disconnection from mains:
Using VLT 8006-8062, 200-240 V wait at
least 15 minutes
Using VLT 8006-8072, 380-480 V wait at
least 15 minutes
Using VLT 8102-8352, 380-480 V wait at
least 20 minutes
Using VLT 8452-8652, 380-480 V wait at
least 40 minutes
Using VLT 8002-8006, 525-600 V wait at least 4 minutes
Using VLT 8008-8027, 525-600 V wait at
least 15 minutes
Using VLT 8032-8302, 525-600 V wait at
least 30 minutes
Using VLT 8052-8402, 525-690 V wait at
least 20 minutes
Using VLT 8502-8652, 525-690 V wait at
least 30 minutes
NB!:
It is the user's or certified electrician's
responsibility to ensure correct earthing and
protection in accordance with applicable
national and local norms and standards.

Earthing

The following basic issues need to be considered
when installing a frequency converter, so as to obtain
electromagnetic compatibility (EMC).
• Safety earthing: Please note that the frequency
converter has a high leakage current and must
be earthed appropriately for safety reasons.
Apply local safety regulations.
•
High-frequency earthing: Keep the earth wire
connections as short as possible.
Connect the different earth systems at the lowest
possible conductor impedance. The lowest possible
conductor impedance is obtained by keeping the
conductor as short as possible and by using the
greatest possible surface area. A flat conductor, for
example, has a lower HF impedance than a round
56
®
VLT 8000 AQUA
conductor for the same conductor cross-section
C . If more than one device is installed in cabinets,
VESS
the cabinet rear plate, which must be made of
metal, should be used as a common earth reference
plate. The metal cabinets of the different devices
are mounted on the cabinet rear plate using the
lowest possible HF impedance. This avoids having
different HF voltages for the individual devices and
avoids the risk of radio interference currents running
in connection cables that may be used between
the devices. The radio interference will have been
reduced. In order to obtain a low HF impedance, use
the fastening bolts of the devices as HF connection
to the rear plate. It is necessary to remove insulating
paint or similar from the fastening points.

Cables

Control cables and the filtered mains cable should
be installed separate from the motor cables so
as to avoid interference overcoupling. Normally, a
distance of 204mm (8 in) will be sufficient, but it is
recommended to keep the greatest possible distance
wherever possible, especially where cables are installed
in parallel over a substantial distance.
With respect to sensitive signal cables, such as
telephone cables and data cables, the greatest
possible distance is recommended with a minimum
of 1m (3 ft) per 5m (15 ft) of power cable (mains
and motor cable). It must be pointed out that the
necessary distance depends on the sensitivity of the
installation and the signal cables, and that therefore
no precise values can be stated.
If cable jaws are used, sensitive signal cables
are not to be placed in the same cable jaws as
the motor cable or brake cable.
If signal cables are to cross power cables, this should
be done at an angle of 90 degrees.
Remember that all interference-filled in- or
outgoing cables to/from a cabinet should be
screened/armoured or filtered.

Screened/armoured cables

The screen must be a low HF-impedance screen.
This is ensured by using a braided screen of
copper, aluminium or iron. Screen armour intended
for mechanical protection, for example, is not
suitable for an EMC-correct installation. See
also Use of EMC-correct cables.
MG.83.A2.02 - VLT is a registered Danfoss trademark