SA Buses with multiple network sensors - Metasys - LIT-12011034 - General System Information - Metasys System - Release 11.0

MS/TP Communications Bus Technical Bulletin

Product name
Metasys System
Document type
Technical Bulletin
Document number
Release 11.0
Revision date
An SA bus supports up to eight network sensors. Figure 1 shows an example of two SA buses, each with eight network sensors.
Note: 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, CGEs, CVEs, FACs, FECs, VMAs, XPMs and IOMs , 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.

Some NS Series Network Sensors and NS Series Discharge Air Sensors models are DIP switch addressable.

Figure 1. SA Bus example showing multiple network sensors