© 2019 UTC Fire & Security Americas Corporation, Inc.
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P/N MAINST-
ATS1741 (ML) • REV B • ISS 13JUN19
ATS1741 RS232 to RS485 Interface Installation
Sheet
EN DA DE ES
FI
FR IT
NL NO PL PT SV
EN: Installation Sheet
Mounting the unit
The board has a standard Aritech ‘B’ size footprint, mountable
in an existing Aritech metalwork.
Connections J2
•
+12 V: 12 VDC supply input. 100 mA maximum.
•
0 V: Negative supply.
•
D+: Positive data connection of the RS485 databus.
•
D−: Negative data connection of the RS485 databus.
Units can be up to 1.5 km from the 4-door DGP or control
panel, depending on the type of cable used. Recommended
cable is WCAT 52/54; 2-pair twisted, shielded, data cable.
Connections J1
•
TX: RS232 data transmit.
•
RX: RS232 data receive.
•
CTS: Clear to send.
•
RTS: Request to send.
•
GND: Isolated RS232 ground.
LEDs
•
TX LED: LED flashes to indicate data is being received in
as RS232
and transmitted out as RS485.
•
RX LED: LED flashes to indicate data is being received in
as RS485 and transmitted out as RS232.
Extended distances between Titan and
ATS1801
ATS1741 (RS485 to RS232 interface) to PC
ATS1741 (RS232)
PC (RS232)
Pin Names
Pin Names
DB25
DB9
TX
RX
3
2
RX
TX
2
3
*CTS
*Not connected
6, 8, 20
1, 4, 6
*RTS
*Not connected
–
–
GND
GND
7
5
*Link RTS-CTS
*Link RTS-CTS
4-5
7-8
ATS1741 (RS485 to RS232 interface) - ATS1741 (RS485 to RS232
interface)
ATS1741
(RS485)
ATS1741
(RS485)
Remarks
+12 V
0 V
+12 V
0V
Connect to a 12 VDC power supply from
one control panel
D+
D+
D
−
D−
Caution:
Do not power the ATS1741 from different power
supplies unless you disconnect the +12 V wiring between
those units. Ensure the power supplies are isolated, especially
the GND.
ATS1741 (RS485 to RS232 interface)
– ATS1801 (Computer/Printer
interface)
ATS1741 (RS232)
ATS1801 Port Computer
TX
RxD
RX
TxD
CTS*
*Not connected
RTS*
Not connected
GND
GND
*Link RTS-CTS
*+12 V on CTS
Data bus System Via Modem
The shield of each length of data cable is only connected to
earth at one end.
The connections between ATS1741 and the modem are as
follows.
