User's Manual

ALC LF BUS Beacon – Installation Guide
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Page 2 of 12
V2/Dec 2014
Primary/Secondary Synchronization
Up to three LF BUS Beacons can be deployed in ‘Primary–Secondary’ topology to cover large double-doors or architectural complex indoor
entrance/exit areas.
Note: When you connect two secondary LF BUS Beacons, you must install them on either side of the primary LF BUS Beacon. For example,
install one to the right of the primary, and install the second to the left of the primary.
When deploying this topology, the LF fields generated by the secondary beacons MUST BE synchronized to pulse at precisely the same
moment in time as the LF field generated by the primary unit in order to avoid mutual interference between any of the LF fields.
To implement Primary/Secondary Synchronization, users must physically connect a Sync Data Link (typically using a 2x2x26 Category 5 cable)
between the GND and SYNC terminals of the Primary Beacon and all of the Secondary devices.
Primary Secondary
Primary/Secondary Synch Data Connection Diagram
Note: It is not necessary to connect each beacon to a different Junction Box as in the diagram. One Junction Box can power two or three as
well.