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MSD Multi-Axis System Operation Manual DC-AC Servo Drive
•
Route long cables in places not be susceptible to interference. Otherwise
coupling points may be created.
•
Twist wires for the same electrical circuit.
•
Ideally, route the signal cables separated from encoder cables.
•
All signal cables should be combined and routed away upward.
•
Avoid extending cables via terminals.
4.2.3
Earthing measures
All earthed points and components must be routed directly to the central earthing
point (e.g. PE rail, main earth) with as low an impedance as possible and with good
conductivity. In this way an earthing system is produced that connects all connections to
the earthing point in a star topology. This central earthing point is to be clearly defined.
This earthing point can be extended to the entire backing plate with an effective EMC
connection.
You should take into account the following points for the earthing:
•
Earthed surfaces act as shielding measures and reduce electromagnetic fields
in the surrounding area. For this reason metal surfaces should be connected
to ground with low-impedance HF connections. In terms of EMC it is not the
cross-section of the cable that is definitive, but the surface over which high
frequency currents caused by the skin effect can flow awa .
•
Connect the protective earth conductors for the components in the switch
cabinet using a star topology.
•
Avoid the use of connectors.
•
Also connect the walls and doors of the switch cabinet to ground.
•
Larger openings in the switch cabinet (window, fan, display) degrade the
shielding effect of the cabinet and must be protected with additional shielding
measures for the HF range.
•
Earth unused cores at one end as a minimum so that there is no electrostatic
charging.
•
Free contact areas of paint and corrosion and make large area connections.
4.2 Effective EMC installation
4.2.1
Cable type
•
Use only shielded mains, motor and signal cables as shown in Figure 4.1. For all
shielded connections use cables with double copper braiding with 60 to 70 %
coverage.
•
If it is necessary to lay very large cable cross-sections, instead of shielded
cables it is also possible to use separate individually shielded wires.
NOTE
Only use the DC link connections supplied for the electrical coupling of the
devices. If extending the DC link coupling is unavoidable, it is imperative you
pay attention to the requirements in
. On the usage of
connection cables that do not meet the requirements, Moog does not provide
any guarantee for stable, safe operation.
4.2.2
Routing of cables
You should take into account the following points on laying the cables:
•
Route mains, motor and signal cables separated from one another. Maintain a
distance of at least 200 mm (7.87 in).
•
For smaller distances use separators for shielding; fasten the separators directly
and conductively to the backing plate.
•
Route the cables close to ground potential. On the usage of cable ducts made
of plastic, the cable ducts must be fastened directly to the backing plates or the
frame. Open space must not be spanned, as otherwise the cables could act
like antennae.
•
Route motor cables without interruptions (e.g. not via terminals) and lay them by
the shortest route out of the switch cabinet.
•
If a motor contactor or a motor choke is used, the component should be
positioned directly at the DC-AC Servo Drive and the shielding on the motor
cable should not be stripped back too far.
•
Avoid unnecessary cable lengths and "loops of spare cable".
moog
Id. no.: CA97554-001 0
5
/2017
4 Electrical installation
