ABB AC 800F, Mounting And Installation Instructions Manual

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4 Cabling the AC 800F
4-92
The terminating resistors are connected to terminals 1 ... 8 of terminal block TK 870F,
i.e. with active termination you have to cable the nodes (I/O units) with terminals
14 ... 21 to avoid branches.
When cabling the CAN bus observe the following rules:
•
Always provide a CAN termination on the first and last bus node. If the first or
last bus node is a Freelance 2000 I/O unit, plug the CAN termination DSU 01 to
connector I/O in or I/O out of the link modules DLM 01 and DLM 02.
If the AC 800F is located at the end of a bus, you can make either an internal
termination, or an external termination on the terminal block TB 870F. The
advantage of the internal termination is that the CAN cable DSU 07 or DSU 011
can be connected directly and without requiring a terminal block TB 870F.
•
Using no CAN terminations will cause malfunctions of the CAN bus.
•
Always fasten CAN terminations DSU 01 and CAN cables with screws.
•
The CAN cable is sufficiently grounded via the connector, or is put on the P-
terminal of the terminal block TB 870F, respectively.
•
The order of the AC 800F and the I/O units on the bus is arbitrary.
•
Put the shield of TK 811F or TK 817F on terminal P of the terminal block
TB 870F.
•
If the shield is not put on properly, neither RFI suppression nor
EMI/RFI shielding of the system can be guaranteed.
•
Use either an internal or an external termination. Do not use both
of them, this will cause communication problems.