Motor Connection - Danfoss VLT AutomationDrive Design Manual

Electrical Installation
8 8
Illustration 8.4 Mains connection size C1 and C2 (IP 21/ NEMA
Type 1 and IP 55/66/ NEMA Type 12).
Illustration 8.5 Mains connection size C3 (IP20).
160
FC 300 Design Guide
91
92
93
L1
L2
L3
95
MG.33.BD.02 - VLT
Illustration 8.6 Mains connection size C4 (IP20).
Usually the power cables for mains are unscreened cables.

8.1.3 Motor Connection

To comply with EMC emission specifications, screened/
armoured cables are recommended. For more information,
see 3.4.2 EMC Test Results.
See section General Specifications for correct dimensioning
of motor cable cross-section and length.
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.
Connect the motor cable screen to both the decoupling
plate of the frequency converter 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 frequency converter.
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.
®
is a registered Danfoss trademark
U
V W