Biometric Readers with swipe capacitive sensor v2.0
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a
Company
Visual
Corporation
Plus
6.1
Biometric readers in network with EWS controllers
The Biometric readers are connected through RS485 bus. The same RS485 bus that the EWS controllers are
connected to.
Maximum units in one network (EWS + Biometric readers) is 32.
If there are more than 32 units in one network, please utilize RS 485 HUB to connect.
The RS485 Line should be configured in the form of a daisy chain, NOT in a form of a star. If star must be used in
some points, keep the stubs from the RS485 backbone as short as possible. Maximum length of the stub is
dependant of the installation (total number of devices in RS486 line (total cable length, termination, cable
type...) so recommendation is to keep stubs shorter than 10 meters and keeping mind that this can be possible
reason if there is errors in communication with PC software
The cable must be twisted and shielded with a min. 0.5 mm2 cross section.
Connect the ground (0V) of each unit in the RS 485 Line using a third wire in the same cable.
The shield of the communication cable between two devices must be connected to the EARTH from ONE side of
the RS 485 Line. Use the side that has earth connection to building grounding network.
6.2
RS 485 termination resistors
For proper communication over a RS485 network, the end points must be terminated with a 120 Ohm resistor.
There are on board 120 Ohm termination resistors on the EWS controller. Those termination resistors are
selected by jumper.
Note: The RS485 Communication Line must be made in a daisy chain, NOT in a star type.
