TCP/IP
50m
max.
50m
max.
50m
max.
Switch
5.1 CONNECTING BIOMETRIC READERS IN SAME RS485 LINE WITH THE 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 RS485 line (total cable length, termination, cable type...) so recommendation is to keep stubs shorter than
5 meters, keeping in mind that this can be possible reason for errors in communication with PC software
T
he cable must be twisted and shielded with a min. 0.
2
mm2 cross section.
C
onnect the ground (0V) of each unit in the RS 485 Line using a third wire in the same cable.
T
he 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
the
building
’s
grounding network.
RS485
Jumper for
RS485 termination
1 km max / 32 Units (EWS + Biometric Readers)
50 ohm
50 ohm
TCP/IP
gnd
gnd
Stub
max. 5m
Jumper for
RS485 termination
5.2 CONNECTING BIOMETRIC READERS WHEN ALL THE CONTROLLERS HAVE TCP/IP COMMUNICATION
When all the controllers are connected via TCP/IP, then the RS485 network becomes local (from Reader 1 to the Controller then
to the Reader 2).
Connect the readers directly to the Rs485 terminals in each controller.
If the distance Reader-Controller is high (50meters) and if the communication with the reader can not be established, then
terminate the RS485 network by closing the jumper in the EWS Controller or as described in chapter 4.
6
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