Paxton BLU Expansion Controller Installation Manual page 6

Connecting to Paxton BLU Expansion Controllers via RS485 Data Connection
You can connect up to a maximum of 24 Paxton BLU Expansion units to one Master unit (for a total of 50 doors). The Master unit handles all
communication with the outside world. Mulitple Master units can be installed on a single site. These can be logically grouped in the software to
appear as a single site.
The Master unit connects to Expansion units through a dedicated RS485 connection. Each cable section, between Master and Expansion and
between Expansion and Expansion has its own section of cable carrying the half-duplex RS485 communication between units. Termination of
the 485 data bus is done automatically by each Master and Expansion controller, eliminating the need for field installed bus termination resistors.
Reader and Data Cable – Shield Drain Connections
GSM
ETHERNET
DOOR 1
Shield drain
Data cable MUST have the spare wires and shield drains connected to the 0V terminals
throughout the bus or communication errors may occur. Reader and keypad 'drain wires' , where
provided, should be connected to the Black (0V) terminal.
MASTER UNIT
INPUT INPUT AC 100-240V AC 100-240V
50 / 60 Hz 50 / 60 Hz
1.2A 1.2A
OUTPUT OUTPUT DC 13.8V DC 13.8V 2A 2A
RS485
DOOR 2
MASTER UNIT RS485
EXPANSION UNIT
INPUT AC 100-240V
50 / 60 Hz
1.2A
OUTPUT DC 13.8V 2A
DOOR 3 DOOR 4
Shield drain
MIDDLE EXPANSION RS485
RS485
DOOR 49
Shield drain
END EXPANSION RS485
EXPANSION UNIT
INPUT AC 100-240V
50 / 60 Hz
1.2A
OUTPUT DC 13.8V 2A
DOOR 50
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