Correct Wiring of Electrically Isolated CAN Networks
6.3.2 Device Cabling
NOTICE
If single shielded
double
twisted pair cables are used, realize the T-connections by means
of connectors that support connection of two CAN cables at one connector where the
cable’s shield is looped through e.g. DSUB9 connector from ERNI (ERBIC CAN BUS
MAX, order no.:154039).
The usage of esd’s T-connector type C.1311.03 is not recommended for single shielded
double
twisted pair cables because the shield potential of the conductive DSUB housing is
not looped through this T-connector type.
If a mixed application of single twisted and double twisted cables is unavoidable, take care
that the CAN_GND line is not interrupted!
Figure 9:
Example of proper wiring with single shielded double twisted pair cables
6.3.3 Termination
●
A termination resistor has to be connected at both ends of the CAN bus.
If an integrated CAN termination resistor which is equipped at the CAN interface at the end
of the bus is connected, this one has to be used for termination instead of an external CAN
termination plug.
●
9-pin DSUB-termination connectors with integrated termination resistor and male and
female contacts (gender changer) are available from esd (order no. C.1303.01).
●
9-pin DSUB-connectors with integrated switchable termination resistor can be ordered e.g.
from ERNI (ERBIC CAN BUS MAX, female contacts, order no.:154039).
CAN-PC104/331
Hardware Manual • Doc. No.: C.2012.21 / Rev. 1.6
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