User's Manual

ALC LF BUS Beacon – Installation Guide
www.elpas.com
Page 10 of 12
V2/Dec 2014
RS-485 BUS/Stub Topology
The RS-485 BUS MUST Be wired using a BUS/Stub topology where the BUS Master (a RF IP Reader or an ELC Controller) is
connected anywhere along the BUS. The topology supports data transmission between the BUS Master and up to 15 Elpas
BUS Devices (such as RF or IR Readers; LF Beacons, Remote Display Panels I/O Boxes and Proximity Readers) using multiple
Elpas RS-485 Junction Boxes (P/N: 5-JBA10485).
IMPORTANT NOTE: Only 1 RF IP Reader/ELC Controller and up to 7 RF BUS Readers may coexist together on a single BUS.
200M/650Ft: Max. BUS length 10M/30Ft: Max. Stub length 100 Ohm Termination: Required each end of the BUS.
Recommended Cable/Power Supply Types:
BUS Backbone:
CAT5 solid (4x2x26AWG).
Power: Three twisted pairs
(six conductors) between junction boxes.
Data: One twisted pair (two conductors) between junction boxes.
Power: 25 VDC/1A Limited.