©
CIAS Elettronica S.r.l.
Ed. 1.0
Installation Handbook
page
40
of
59
MANTA 50 – 80
3.4 Serial Line RS-485
3.4.1 RS - 485 / 232 Network Connection Interface
A standard RS 485 serial interface is provided on both transmitter and receiver of the MANTA
barrier. The communication parameters are the following:
Mode:
Asynchronous - Half-Duplex
Baud rate:
9600 b/s
Character length:
8bit
Parity control:
No Parity
Stop bit:
1
3.4.2 RS -485 Serial Line connections
The way of laying down the cable must be “multidrop” type (BUS), and the derivations for units
connection as short as possible. Connect to the terminal 4 “LO” (“RS 485 –“ negative data line );
to the terminal 3 “LH” (“RS 485+” positive data line ) and to the terminal 2 “GND” (data ground
line) of the terminal block MS2 for the Receiver and Transmitter PCB. To connect a PC on serial
line is necessary to use a serial line converter RS 485/232 included in MWA TEST or
WAWETEST Softwares.
Cable for connection of all the heads Rx and Tx
To the maintenance P. C. with MWA TEST Software
Connector
interface
MS2(Rx e Tx),
Connector
25 pin
N° N°
Symbol
Function
1 12
+13,8
Power supply (13,8 V
) per for 485/232 converter
2 9
GND
Ground data and power supply for 485/232 converter
3 10
LH 485
High Line for RS 485
4 11
LO 485
Low Line for RS 485
3.4.3 Network Configuration and Signal Repeaters
The interconnection cable concerning barrier management through a remote P.C. must be
suitable for a RS485 serial data line, i.e., it must be a
low capacity cable with twisted and
shielded wires (70 pF/mt
.) for example “Belden 9842”.The limit distances of the RS 485
connection is 1200 meters. For longer distances use one or more interface Regenerators (BUS
REP), see figure below. The way of laying down the cable must be of BUS type, and the
derivations for units connection as short as possible. It is possible to lay down the cable in
different manner: full stellar; mixed, stellar and BUS type, using Repeaters / Regenerators and
interface multipliers (BUS REP), see figure below. The total number of units (Tx and Rx) that can
be connected to the line are 32, for an higher number of units, it is necessary the use of one or
more line regenerator RS 485, this is true also in case of cable length less than 1200 metres.
Shield connection continuity must be guaranteed to properly protect the cited line from induced
noise. To this concern the shield will have to be GROUNDED only in one point, i.e., near the
power supply unit. The power supply voltage to the RS485 / RS 232 interface converter must be
delivered by a local power supply unit, which will have to be placed near the converter proper For
the central COM-BS connection, the serial line coming from the barriers can be used directly
without any conversion.
Summary of Contents for MANTA 50
Page 55: ...NOTE...
