ABB OmniCore C90XT, Руководство по эксплуатации продукта

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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.
Shielding example
The below example shows the shielding of a d-type connector:
xx1700001320
A A dimpled connector body makes multiple bonds to the mating connector
body all around its periphery, 360° bonding.
B Metal, or metallized, back shell makes 360° bond to the connector body.
C The cable shield is exposed and 360° clamped to the back shell. A tight fit
is a must.
Many other 360° bonding methods and types of 360° shielded connectors are also
acceptable.
Shield pigtail termination
Shield pigtail termination, as shown below, shall be avoided. If a pigtail connection
cannot be avoided, make it as short as possible.
xx1700001321
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66 Product manual - OmniCore C90XT
3HAC073706-001 Revision: D
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3 Installation and commissioning
3.5.2 Connecting cables to the controller
Continued