Shielded Control Cables - Danfoss VLT CDS 803 Manual

VLT® Compressor Drive CDS 803
Design Guide
1 Aluminum-clad with copper wire.
2 Twisted copper wire or armored steel wire cable.
3 Single-layer braided copper wire with varying per-
centage shield coverage. This is the typical reference
cable.
4 Double-layer braided copper wire.

6.5.7 Shielded Control Cables

Usually, the preferred method is to secure control and serial communication cables with shielding clamps provided at both ends to
ensure the best possible high frequency cable contact.
If the ground potential between the drive and the PLC is different, electric noise could disturb the entire system. Solve this problem
by fitting an equalizing cable as close as possible to the control cable. Minimum cable cross-section: 16 mm
PLC FC
PE PE
<10 mm
PE PE
1
2
Illustration 38: Shielding Clamps at Both Ends
2
1 Minimum 16 mm
2 Equalizing cable
6.5.7.1 50/60 Hz Ground Loops
With long control cables, ground loops may occur. To eliminate ground loops, connect 1 end of the shield to the ground with a
100 nF capacitor (keeping leads short).
PLC FC
PE
PE <10 mm
100nF
Illustration 39: Connection with a 100 nF Capacitor
6.5.7.2 Avoid EMC Noise on Serial Communication
This terminal is connected to ground via an internal RC link. Use twisted-pair cables to reduce interference between conductors. The
recommended method is shown in the following illustration.
FC FC
69 69
68
68
61 61
PE PE
<10 mm
PE PE
1
2
Illustration 40: Twisted-pair Cables
2
1 Minimum 16 mm
2 Equalizing cable
Alternatively, the connection to terminal 61 can be omitted.
60 | Danfoss A/S © 2021.05
(6 AWG)
(6 AWG)
5 Twin layer of braided copper wire with a magnetic,
shielded/armored intermediate layer.
6 Cable that runs in copper tube or steel tube.
7 Lead cable with 1.1 mm (0.04 in) wall thickness.
Electrical Installation
Considerations
2
(6 AWG).
AJ330233902305en-000201 / 130R0596