Motor Connection - Danfoss FC 300 Operating Instruction

FC 300 Operating Instructions

Motor Connection

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NB!:
Motor cable must be screened/armoured.
If an unscreened/unarmoured cable
is used, some EMC requirements are
not complied with. For more information, see
EMC specifications in the VLT AutomationDrive
FC 300 Design Guide.
See section General Specifications for
correct dimensioning of motor cable
cross-section and length.
• Use a screened/armoured motor cable to
comply with EMC emission specifications. If an
unscreened/unarmoured cable is used, some
EMC requirements are not complied with. For
more information, see EMC specifications in the
VLT AutomationDrive FC 300 Design Guide.
Keep the motor cable as short as possible to
•
reduce the noise level and leakage currents.
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.
Screening of cables: Avoid installation with
•
twisted screen ends (pigtails). They spoil the
screening effect at higher frequencies. If it is
necessary to break the screen to install a motor
isolator or motor contactor, the screen must be
continued at the lowest possible HF impedance.
• 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 impedance.
Screening of cables:
twisted screen ends (pigtails). They spoil the
screening effect at higher frequencies. If it is
necessary to break the screen to install a motor
isolator or motor contactor, the screen must be
continued at the lowest possible HF impedance.
Cable-length and cross-section:
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.
Switching frequency:
are used together with LC filters to reduce
20
How to Install
Avoid installation with
The frequency
When frequency converters
MG.33.A7.02 - VLT is a registered Danfoss trademark
the acoustic noise from a motor, the switching
frequency must be set according to the LC
filter instruction in Par. 14-01.
Fasten decoupling plate to the bottom of FC 300
1.
with screws and washers from the accessory bag.
2. Attach motor cable to terminals 96 (U),
97 (V), 98 (W).
Connect to earth connection (terminal
3.
99) on decoupling plate with screws from
the accessory bag.
Insert plug connectors 96 (U), 97 (V), 98
4.
(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.
Motor connection ≤ 7.5 kW IP 20 (A1, A2 and A3 enclosures)