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1.
2.
3.
4.
5.
The conductibility of the shield material.
The contact resistance between the individual shield conductors.
The shield coverage, that is, the physical area of the cable covered by the shield - often stated as a percentage value.
Shield type (braided or twisted).
e7
5z
a1
66
.1
4
0.01
0.1
1
10
100
10ˉ²
10ˉ³
10ˉ¹
1
10¹
10²
10⁴
10³
10⁵
1
m
Ω
/m
MHz
2
3
4
5
6
7
Illustration 63: Transfer Impedance (Z
T
)
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.
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.
10.4.2 Preparing Cable Entry Holes
Procedure
Remove cable entry from the drive. Avoid that foreign parts fall into the drive when removing the knockouts.
Support the cable entry where the knockout is to be removed.
Remove the knockout with a strong mandrel and a hammer.
Remove burrs from the hole.
Mount the cable entry on the drive.
10.4.3 Specifications of Entry Holes
The suggested uses of the holes are recommendations, but other solutions are possible. Unused cable entry holes can be sealed
with rubber grommets (for IP21).
AJ300847815559en-000101 / 130R0337 | 113
Danfoss A/S © 2020.09
Electrical Installation
Considerations
VLT® AQUA Drive FC 202
Design Guide