Connection Of Multiple Motors - Danfoss VLT AQUA Drive FC 202 Design Manual

System Integration
Even good shielding does not fully eliminate the radiation.
System components located in radiation environments
must operate without degradation.

3.4.6 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:
•
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 3.12.
•
The total motor cable length specified in
Table 3.4, is valid as long as the parallel cables are
kept short (less than 10 m (33 ft) each), see
Figure 3.14 and Figure 3.15.
•
Consider voltage drop across the motor cable, see
Figure 3.15.
•
For long parallel cables, use an LC filter, see
Figure 3.15.
•
For long cables without parallel connection, see
Figure 3.16.
NOTICE!
When motors are connected in parallel, set 1-01 Motor
Control Principle to [0] U/f.
Figure 3.11 Common Joint Connection for Short Cable Lengths
MG20N622
Design Guide
Figure 3.12 Common Joint Connection for Long Cable Lengths
for
INV
Figure 3.13 Parallel Cables without Load
Figure 3.14 Parallel Cables with Load
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