VLT
®
4000 VT
Installation
NOTE
If an unshielded cable is used, some
EMC requirements are not complied with,
see
EMC test results
.
If the EMC specifications regarding emission are
to be complied with, the motor cable must be
shielded, unless otherwise stated for the RFI filter
in question. It is important to keep the motor cable
as short as possible so as to reduce the noise level
and leakage currents to a minimum.
The motor cable shield must be connected to the
metal cabinet of the AFD and to the metal cabinet of
the motor. The shield connections are to be made
with the biggest possible surface (cable clamp).
This is enabled by different installation devices in
the different AFDs. Mounting with twisted shield
ends (pigtails) is to be avoided, since these spoil
the shielding effect at higher frequencies.
If it is necessary to break the shield to install a
motor isolator or motor contactor, the shield must be
continued at the lowest possible HF impedance.
MG.40.A7.22 - VLT is a registered Danfoss trademark
47