STC SmartScanIS, User Manual

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14 January 2021, SmartScanIS User’s Guide for Union Pacific, EUD-2016026-00 Rev.2
4.6.1.12 Connector P16
The 10-pin connector P16 appears on System Interface boards. This connector allows access
to eight optically isolated digital inputs. This connector is intended for future expansion.
4.6.1.13 Connector P17
The 10-pin connector P17 connects to the 2300-357 Efficiency Test panel. Chapter 14 –
Using the Efficiency Test Panel tells how to arm and disarm the panel.
4.6.1.14 Terminal Block TB3
On the System Interface board, the 6-position terminal block TB3 is used to connect to RS485
devices, such as wind speed and wind direction instrumentation.
Terminal Name Function
12VDC Protected with a 100mA, self-restoring fuse. Used for powering
external instrumentation.
TX
¯¯
RS485 TX
¯¯ - (Connected to RX ¯¯ through J1)
TX RS485 TX+ (Connected to RX through J2)
RX
¯¯
RS485 RX
¯¯ - (Connected to TX ¯¯ through J1)
RX RS485 RX+ (Connected to TX through J2)
GND Used for powering external instrumentation.
4.6.1.15 Plug P9 (COM1)
On the System Interface board, the DB9M plug P9 can be configured in one of three different
modes of communications, RS232, RS422, and RS485. The configuration in which the board
ships from the factory is RS485. All modes are described in this section for reference.
For RS232 communications:

Install U8 (MAX489) chip

Install U7 (MAX232) chip

Ignore jumpers J1 and J2

Short jumper J4

Remove any communications wiring from terminal block TB3

Connect null modem communications cable to plug P9