Danfoss VLT 6000, Быстрая настройка

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6
MG.60.C4.02 – VLT is a registered Danfoss trademark
VLT
®
6000 HVAC
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Screened/armoured cables
The screen must be a low HF-impedance
screen. This is ensured by using a braided
screen of cobber, aluminium or iron. Screen
armour intended for mechanical protection, for
example, is not suitable for an EMC-correct
installation.
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Extra protection with regard to indirect
contact
ELCB relays, multiple protective earthing or
earthing can be used as extra protection,
provided that local safety regulations are
complied with.
In the case of an earth fault, a DC content may
develop in the faulty current.
Never use ELCB relays, type A, since such
relays are not suitable for DC fault currents. If
ELCB relays are used, this must be done in
accordance with local regulations.
If ELCB relays are used, they must be:
• Suitable for protecting equipment with a
direct current content (DC) in the faulty
current (3-phase bridge rectifier)
• Suitable for power-up with short
charging current to earth
• Suitable for a high leakage current.
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RFI switch
Mains supply isolated from earth:
When the VLT frequency converter is supplied
from an isolated mains source (IT mains), the
RFI switch must be closed (OFF). In the OFF
position, the internal RFI capacitors (filter
capacitors) between the chassis and the
intermediate circuit are cut out so as to avoid
damaging the intermediate circuit and to
reduce the earth leakage currents (see IEC
1800-3).
NB!
When the RFI switch is set to OFF para-
meter 407 Switching frequency max is
only allowed to be set to factory setting.
NB!
The RFI switch is not to be operated
with mains supply connected to the
unit. Check that the mains supply has
been disconnected before operating the RFI
switch.
NB!
The RFI switch disconnects the
capacitors galvanically; however,
transients higher than approx. 1,000 V
will be bypassed by a spark gap.
Reliable galvanic isolation (PELV) is
lost if the RFI switch is placed in the
OFF position. This means that all
control in- and outputs can only be
considered low-voltage terminals with basic
galvanic isolation. In addition, the VLT 6000
HVAC EMC performance will be reduced if
the RFI switch is placed in the OFF position.
Mains supply connected to earth:
The RFI switch must be ON for all installations
on earthed mains supplies.
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High voltage test
A high voltage test can be carried out by short-
circuiting terminals U, V, W, L
1
, L
2
and L
3
and
energizing by max. 2.5 kV DC for one second
between this short-circuit and the chassis.
NB!
The RFI switch must be closed (position ON)
when high voltage tests are carried out. The
mains and motor connection must be
interrupted in the case of high voltage tests of
the total installation if the leakage currents are
too high.