Control Wire Isolation - Danfoss VLT AQUA Drive FC 202 Design Manual

System Integration
3 3
Figure 3.15 LC Filter for Long Parallel Cables
Enclosure sizes
A1, A2, A4, A5
A2, A4, A5
A2, A4, A5
A3, A4, A5
B1, B2, B3, B4,
C1, C2, C3, C4
A3
B4
C3
Table 3.17 Maximum Cable Length for Each Parallel Cable

3.4.7 Control Wire Isolation

Harmonic interference generated by motor cabling can
degrade control signals in the drive control wiring and
result in control faults. Motor cables and control wiring
should be separate. Interference effects decrease signifi-
cantly with separation.
•
The distance between control wiring and motor
cables should be more than 200 mm (11.8 in).
•
Divider strips are essential with smaller
separations or interference may be coupled in or
transferred.
•
Control cable shields must be connected at both
ends in the same way as motor cable shields.
60
®
VLT
Power Size [kW
Voltage [V]
(hp)]
400
0.37–0.75 (0.5–1)
500
400
1.1–1.5 (1.5–2)
500
400
2.2–4 (3–5)
500
400
5.5–7.5 (7.5–10)
500
400
11–90 (15–125)
500
1.1–7.5 (1.5–10) 525–690
11–30 (15–40) 525–690
37–45 (50–60) 525–690
Danfoss A/S © 09/2014 All rights reserved.
AQUA Drive FC 202
Figure 3.16 Long Cables in Series Connection
1 cable [m (ft)] 2 cables [m (ft)]
150 (500) 45 (148)
150 (500) 7 (23)
150 (500) 45 (148)
150 (500) 45 (148)
150 (500) 45 (148)
150 (500) 45 (148)
150 (500) 45 (148)
150 (500) 45 (148)
150 (500) 75 (250)
150 (500) 75 (250)
100 (330) 50 (164)
150 (500) 75 (250)
150 (500) 75 (250)
•
Shielded cables with twisted conductors provide
highest attenuation. The attenuation of the
magnetic field increases from around 30 dB with
a single shield to 60 dB with a double shield and
to approximately 75 dB if the conductors are also
twisted.
3 cables [m (ft)] 4 cables [m (ft)]
8 (26.3) 6 (20)
4 (13) 3 (10)
20 (66) 8 (26.3)
5 (16.4) 4 (13)
20 (66) 11 (36)
20 (66) 6 (20)
20 (66) 11 (36)
20 (66) 11 (36)
50 (164) 37 (123)
50 (164) 37 (123)
33 (108.3) 25 (82)
50 (164) 37 (123)
50 (164) 37 (123)
MG20N622