RC Systems ST-72, Instruction Manual

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ST-72 User's Manual
Document: UM-1007 Revision Level A
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JP6 (com port 4) connects the RS-485 port’s RX & TX lines, simplifying 2 wire daisy chains
by providing additional terminals for incoming and outgoing cables. For example,
installing the two COM 1 jumpers connects screw terminals 1 & 5 and terminals 3 & 7 at
TB1. RS-485 terminating resistors are installed by moving the jumpers at JP1 (com port
3) and JP4 (com port 4) to position 1. These resistors should not be installed if the port
is not at the end of the communication line.
TB1 allowes
external Alarm
Reset contacts.
J3 Ribbon connector
to optional AR PCB.
J5 Ribbon connector
to optional IS PCB.
Ethernet Port
Fuses DC OUT power to
option boards that require 24
VDC. ( 2A 5x20m)
TB4 terminals 2,4 +24VDC &
6,8 -24VDC (COM) provide
Fused 24 VDC power to ST-72
option boards requiring such
power.
Apply only nominal 24 VDC
(min 10 VDC, max 30 VDC)
power to terminals 1,3
+24VDC & 5,7 -24VDC
(COM) of TB4.
J9 is 40 pin ribbon to main
controller.
J1 & J2 connect to I2C optional
I/O.
Figure 3-1
Main I/O Board
3.2 INPUT / OUTPUT OPTION BOARDS
Telephone style RJ11 connections (J3 and J4 on all option Boards) are used to add
optional 16 channel analog and digital I/O. All option Boards must have 24 VDC applied
to TB3 or TB4 which are tied together making daisy chaining the 24 VDC from one
option board to another possible. All I/O options except the Programmable Relay Board
have LEDs to indicate which channel and alarm they are assigned to. The Programmable
Relay is not limited to groups of 16 channels like the other options so the LEDs are not
required. The connected I/O screen in the
Diagnostics Menu is also useful for displaying
and programming the connected I/O Boards.