NORD Drivesystems BU0260 - Manual (Page 99)

8 Additional information
BU 0260 GB Subject to technical amendments 99
8.1.3 Cable layout and shielding (EMC measures)
If EMC measures are not in place, high-frequency interference which is mainly caused by switching processes
or lightning often causes electronic components in the bus subscribers to be faulty and error-free operation can
no longer be ensured.
Appropriate shielding of the bus cable reduces electrical interference which can arise in an industrial
environment.
The best shielding characteristics are achieved with the following measures:
 Avoid long connections between bus subscribers
 Shield the bus cable on both ends with large-area connection to the plug housing
 Avoid spur cables
 Avoid extensions to bus cables via plug connectors
Bus lines should be laid with a minimum spacing of 20cm to other lines which carry a voltage higher than 60V.
This applies to lines laid inside and outside of control cabinets.
Special attention should be paid to bending radii:
Fixed cable Freely laid cable Bending radius of cable
Minimum radius
5 x cable diameter
Minimum radius
10 x cable diameter
Correct Incorrect
NOTE
If earthing potential values are different, transient current may flow through shielding which
is connected on both sides. This may be a danger to electronic components. Differences in
potential must be reduced by means of adequate potential equalisation.
8.1.4 CiA (CAN in Automation) recommendations
Important information about CAN and CANopen can be found in Internet under www.can-cia.org and
www.drivecom.org .