Shielding Measures - Keba ServoOne Series Operation Manual

4.2.4

Shielding measures

You should take into account the following points for the shielding measures:
y Use only shielded mains, motor and signal cables as shown in Figure 4.7,
p. 35. For all shielded connections, use cables with double copper braiding
with 60 to 70% coverage.
y Connect the shield at both ends using a large area connection. Extending the
shield to the earthing point using a wire (pigtail) reduces the shielding effect by
up to 90 %.
Figure 4.1 CORRECT shield connection
Figure 4.2 INCORRECT shield connection - do not extend to the earthing point (pigtail)
ID no.: 1101.21B.6-00 Date: 04/2020
Electrical installation
Figure 4.3 ServoOne shield connection
Do not strip back too far the shield.
y
Shields are not allowed to be used to carry power, e.g. as a substitute for the N
y
or PE conductor.
The shielding effect can be improved by laying in metal ducts/tubes.
y
y Shields must be connected at both ends. Additional connection at multiple
points is recommended, otherwise potential equalisation currents may flow in
physically extensive installations.
y The bases of the chokes must have good contact to the switch cabinet ground.
The contact area must be bare metal to establish a good ground connection to
the switch cabinet ground.
Operation Manual ServoOne Supply Unit
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