Engineering Documentation

Table Of Contents
Chapter 2 Network Electrical Systems
RS-485 ALN and FLN (P1) Communications Wiring on Structured Cabling
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Converting SCS Star Segments to RS-485 ALN and FLN
Chain Segments
The Telecommunications (wiring) Closet-to-device outlet will generally be Commercial
Category 5E or IEEE Category 6 cable on new installations. Following information
systems standards, basic link cable runs are limited to 295 ft (90 m) of solid copper
terminated by punch down blocks in the wiring closet and RJ-45 jacks in the field
panel or zone.
SCS segments are wired per TIA 568A (preferred) or 568B. Observing the 295 ft (90
m) restriction allows future conversion to Ethernet Devices in the field panel without
rewiring the SCS segment.
Fig. 29: Punching Down a Device.
Fig. 30: Punching Down the Connecting Blocks to the Wiring Block.