Danfoss VLT AutomationDrive FC 300 Operating Instructions Manual page 24

3. How to Install
See section General Specifications for correct
dimensioning of motor cable cross-section
and length.
Screening of cables:
twisted screen ends (pigtails). They spoil the
screening effect at higher frequencies. If it is
3
necessary to break the screen to install a mo-
tor isolator or motor contactor, the screen
must be continued at the lowest possible HF
impedance.
Connect the motor cable screen to both the
decoupling plate of the FC 300 and to the
metal housing of the motor.
Make the screen connections with the largest
possible surface area (cable clamp). This is
done by using the supplied installation devices
in the FC 300.
If it is necessary to split the screen to install a
motor isolator or motor relay, the screen must
be continued with the lowest possible HF im-
pedance.
Cable-length and cross-section:
quency converter has been tested with a given
length of cable and a given cross-section of
that cable. If the cross-section is increased,
the cable capacitance - and thus the leakage
current - may increase, and the cable length
must be reduced correspondingly. Keep the
motor cable as short as possible to reduce the
noise level and leakage currents.
Switching frequency:
converters are used together with Sine-wave
filters to reduce the acoustic noise from a mo-
tor, the switching frequency must be set ac-
cording to the Sine-wave filter instruction in
Par. 14-01.
24
Avoid installation with
The fre-
When frequency
MG.33.A9.02 - VLT is a registered Danfoss trademark
®
VLT AutomationDrive FC 300 Operating
1. Fasten decoupling plate to the bot-
tom of FC 300 with screws and wash-
ers from the accessory bag.
2. Attach motor cable to terminals 96
(U), 97 (V), 98 (W).
3. Connect to earth connection (termi-
nal 99) on decoupling plate with
screws from the accessory bag.
4. Insert plug connectors 96 (U), 97
(V), 98 (W) (up to 7.5 kW) and motor
cable to terminals labelled MOTOR.
5. Fasten screened cable to decoupling
plate with screws and washers from
the accessory bag.
Illustration 3.2: Motor connection for A1, A2 and
A3
Illustration 3.3: Motor connection for A5 (IP
55/66/NEMA Type 12) enclosure
Instructions