ABB OmniCore V250XT, Product Manual

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Cable type Signal class
• These signals generate a lot of interference and must be
laid separate from control, measurement, and communica-
tion signals.
• The shielding must be connected to a paint-free part of the
panel chassis of the cabinet at both ends of the cable. Any
unshielded cable must be as short as possible.
• The manipulator power cables are routed on the floor and
along the left side of the controller cabinet.
• Cables should not be wound up like coils. This could cause
an magnetic field disturbing the signals. There will also be
a risk of overheating depending on the load.
Power signals
• These signals are very sensitive to interference. To protect
these signals they should not be laid along with the power
signals.
• In the cable, each signal must be twisted with a neutral wire.
• The shielding must be connected directly to the chassis at
both ends of the cable.
Control signals
Measurement signals
Data communication
signals
Shielding cables
When peripheral devices are connected to the robot system, a shielded cable is
necessary to reduce coupling of the inner cable conductors to the environment
they pass through.
Shielding cable requirements
• The best method for shielding is to ground the shield at both ends of the
cable, provided the ends grounding are at the same potential.
• If the grounding points have different electric potentials - grounding both
ends will create a ground loop allowing unwanted current to flow in the shield.
In such cases one end grounding may be used. The grounding point should
then be at the robot controller side.
• Cables carrying analog low-level signals is another exception where the
shield should be grounded at only one end.
• Most data network and field bus types have defined grounding topologies.
If such grounding schemes exist, they should be followed.
• In complex interference environments, two-layer shielding may be required.
The inner shield should be grounded at the controller side only end and the
outer shield should be grounded at both ends. The optimum shielding is a
combination of foil and braid screens.
• The best connection is one in which the shielding is extended up to and
makes a solid 360° connection (shown below) with the ground plane or
chassis.
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70 Product manual - OmniCore V250XT
3HAC073447-001 Revision: B
© Copyright 2020-2022 ABB. All rights reserved.
3 Installation and commissioning
3.5.2 Connecting cables to the controller
Continued