Screw terminal blocks for connecting FC and SA Bus cables - Metasys - LIT-12011034 - General System Information - Metasys System - Release 11.0

MS/TP Communications Bus Technical Bulletin

Brand
Metasys
Product name
Metasys System
Document type
Technical Bulletin
Document number
LIT-12011034
Version
Release 11.0
Revision date
2022-02-07
Language
English

Both the FC bus and SA bus terminations have pluggable screw terminal blocks that allow you to connect the bus devices in a daisy-chain configuration. Connect the devices to the FC bus segments and SA bus as shown in Figure 1.

Note:
  • The SHLD terminal on the FC bus terminal block is electrically isolated from ground and is provided as a convenient terminal for connecting the cable shield in a daisy-chain on the bus segment.
  • Do not mix RJ-style modular (phone) jack and screw terminal devices on the SA bus. Due to the permanent internal SA bus EOL termination contained in CGMs, CVMs, FECs, FACs, IOMs, XPMs and VMAs, using both the phone jack and terminal block effectively puts the EOL termination in the middle of the SA trunk, creating a star network configuration. This configuration violates the RS-485 network wiring guidelines and can cause unpredictable communication problems.
  • Certain MS-IOM models have gray SA/FC terminal blocks rather than blue or brown.
Figure 1. FC Bus and SA Bus terminal block wiring details