General Information About Electrical Installation; Electronics Purchased Without Installation Box - Danfoss VLT FCD 303 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 frequency converter may cause
damage to the equipment, serious injury or death.
Comply with the instructions in this manual, as well as
national and local rules and safety regulations.
Touching the electrical parts may be fatal - even after
the equipment has been disconnected from mains:
Wait at least 4 minutes for current dissipate.
NB!:
It is the responsibility of the user or installer
to ensure correct earthing and protection in
accordance with national and local standards.
Cables
The control cable and the mains cable should be
installed separately from motor cables to prevent
noise transfer. As a rule a distance of 20 cm is
sufficient, but it is recommended that the distance
is as great as possible, particularly when cables are
installed in parallel over large distances.
For sensiti v e signal cables such as telephone or data
cables the greatest possible distance is recommended.
Please note that the required distance depends on the
installation and the sensiti v ity of the signal cables, and
that for this reason exact values cannot be gi v en.
When being placed in cable trays, sensiti v e cables
may not be placed in the same cable tray as the
motor cable. If signal cables run across power
cables, this is done at an angle of 90 degrees.
Remember that all noise-filled inlet and outlet cables
to a cabinet must be screened/armoured.
See also EMC-compliant electrical installation.
Cable glands
It must be assured that appropriate cable
glands needed for the environment are chosen
and carefully mounted.
Screened/armoured cables
The screen must have low HF impedance, which is
achieved by a braided screen of copper, aluminium or
iron. Screen reinforcement intended for mechanical
protection, for example, is not suitable for EMC-correct
installation. See also Use of EMC-correct cables.
10
®
VLT FCD Series
Extra protection
ELCB relays, multiple protecti v e 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 an RCD (ELCB relay), type A, as
it is not suitable for DC faulty currents. If ELCB relays
are used, local regulations must be complied with.
If ELCB relays are used, they must be:
- Suitable for protecting equipment with a DC content
in the faulty current (3-phase bridge rectifier)
- Suitable for a pulse-shaped, brief discharge
on power-up
- Suitable for a high leakage current.
See also RCD Application Note MN.90.GX.02.
High voltage test
A high voltage test can be performed by
short-circuiting terminals U, V, W, L1, L2 and L3,
and applying max. 2160 V DC in 1 sec. between
this short-circuit and PE-terminal.

Electronics purchased without installation box

If the electronic part is purchased without the
Danfoss installation part, the earth connection
must be suitable for high leakage current. Use
of original Danfoss installation box or installation
kit 175N2207 is recommended.
Caution
PE connection
The metal pin in the corner(s) of the
electronic part and the bronze spring in the
corner(s) of the installation box are essential
for the protective earth connection. Make sure they
are not loosened, removed, or violated in any way.
MG.04.B7.02 - VLT is a registered Danfoss trademark