Spectrex Xenon 700 SIL Open-Path Gas Detection System - Manual (Page 72)

SafEye TM Xenon 700S SIL Gas Detector
60 RS-485 Communication Network
B.1 RS-485 Communication Network
By using the RS-485 network capability of the SafEye Xenon 700S Detector
and additional software, it is possible to connect up to 32 Detectors in an
addressable system with four (4) wires only (2 for power and 2 for
communication). Using repeaters, the number of Detectors can be much
larger (32 Detectors for each repeater) up to 247 on the same four (4)
wires. When using the RS-485 network, it is possible to read each Detector
status (FAULT, WARNING, and ALARM).
For more details, consult the factory.
Figure 15: RS-485 Networking for Wiring Option 3