Extension Modules
BERGHOF Automation
60 DC1000_HB_en_2D0982003ZD00.doc
2VF100124FE01.doc
CAN Bus for contact line communications
The transmission circuit voltage level of the SC_CAN signals is 85 V or 110
V at 25 Ohm.
Based on the employed voltage level, all signal carrying lines must exhibit the
same level of contact protection as the power supply (230 / 400 V).
Directly connecting ISO11898 devices to the SC_CAN bus will result in the-
re being destroyed and is therefore prohibited.
Such devices include, for example, remote I/Os, drive controllers and CAN bus
analyzers.
SC_CAN – X3
Pin
assignment
Pin
Signal
Description
1
PE
Protective earth
2
SC
SC_CAN signal
3
PE
Protective earth
The two protective earth (PE) connectors must be laid to the contact line
connection using two separate conductors.
Any other type of circuit construction (e.g., a bridge between the two PE connec-
tions) may result in functional errors or functional inefficiency of the SC_CAN.
Termination
The SC_CAN must be terminated at both line ends.
The values for these terminating resistors deviate from the ISO 11898 (CAN Bus)
standard and they can be ordered separately from BERGHOF (CTR-SC-T2, part
no.: 201601200).
If the SC_CAN bus is incorrectly terminated, its operation can result in the
destruction of the I/O subassembly!
You must ensure that the correct termination is employed!
Baud rate
The preset baud rate for the SC_CAN is 50 KB/sec. The SJA1000 CAN controller
is also in the “self test mode”, that is, when a CAN telegram is correctly transmitted
it is not necessary for a subscriber to send a CAN ACK signal. Should it become
necessary, these factory settings can be altered in the application by using the ap-
propriate CAN library.
