End-of-line termination on the MS/TP Bus - 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

Daisy-chained RS485-protocol networks typically require some type of end-of-line (EOL) termination to reduce interference caused by signal reflection that occurs when data transmissions reach the end of a bus segment and bounce back on the segment. The high baud rates on MS/TP bus applications require robust EOL termination and strict adherence to the EOL termination rules. Figure 1 shows an example of the EOL termination settings on an MS/TP bus application.

The EOL termination requirements for the FC bus are different from the SA bus requirements. See End-of-line termination on local FC Bus and End-of-Line termination on SA Bus for more information.

Also, third-party MS/TP devices, such as TEC26xx Series thermostats, have different EOL termination requirements from Metasys devices on the FC bus. See TEC26xx series thermostats and third-party MS/TP devices for more information.

Figure 1. EOL terminations on an MS/TP Bus