Danfoss VLT AutomationDrive FC 301 Series Design Manual page 152

Electrical Installation
9.7 Additional Motor Information
9.7.1 Motor Cable
All types of three-phase asynchronous standard motors can
be used with an adjustable frequency drive unit. The
factory setting is for clockwise rotation with the adjustable
frequency drive output connected as follows:
Motor
U
2
U
1
FC
96
9 9
Motor
U
2
U
1
FC
96
Figure 9.49 Terminal Connection for Clockwise and Counter-
clockwise Rotation
The direction of rotation can be changed by switching two
phases in the motor cable or by changing the setting of
4-10 Motor Speed Direction.
Motor rotation check can be performed using 1-28 Motor
Rotation Check and following the steps shown in the
display.
150
V W
2 2
V W
1 1
97 98
V W
2 2
V W
1 1
97 98
Design Guide
9.7.2 Connection of Multiple Motors
NOTICE!
Problems may arise at start and at low RPM values if
motor sizes are widely different because small motors'
relatively high ohmic resistance in the stator calls for a
higher voltage at start and at low RPM values.
The adjustable frequency drive can control several motors
connected in parallel. When using parallel motor
connection observe the following:
•
•
•
•
•
•
•
NOTICE!
When motors are connected in parallel, 1-02 Flux Motor
Feedback Source cannot be used, and 1-01 Motor Control
Principle must be set to [0] U/f.
Rev. 2014-04-04 All rights reserved.
VCC+ mode may be used in some applications.
The total current consumption of the motors
must not exceed the rated output current I
the adjustable frequency drive.
Do not use common joint connection for long
cable lengths, see Figure 9.51.
The total motor cable length specified in
Table 5.2, is valid as long as the parallel cables are
kept short (less than 10 m each), see Figure 9.53
and Figure 9.54.
Consider voltage drop across the motor cable,
see Figure 9.54.
For long parallel cables, use LC filter, see
Figure 9.54.
For long cables without parallel connection, see
Figure 9.55.
for
INV
MG33BF22