Pin Assignment

Each serial port–the fixed RS485 port and the configurable RS232/RS485 port–uses an RJ45 female connector. Pins are positioned within the female RJ45 connector for each serial port as follows:

The specified standard–RS232 or RS485–determines the signal assigned to each pin for serial communications:

RJ45 Pin Number

Signal Type

RS232

RS485

1

DTR (data terminal ready)

Reserved

2

DSR (data set ready)

Reserved

3

TXD (transmitted data)

D1

4

RXD (received data)

Reserved

5

GND (common ground)

GND

6

RTS (request to send)

D0

7

CTS (clear to send)

Reserved

8

Cable shield

Cable shield
NOTE: The 171 CBU 78090, 171 CBU 98090 and 171 CBU 98091 RJ45 serial port pin assignments are compatible with serial port pin assignments of legacy Momentum CPUs. However, these pin assignments differ from the M340 family of CPUs.

Serial Cabling Components

You can purchase the following serial cabling components from Schneider Electric:

Part Number

Length

Description

Connector

110XCA28203

6 m

Momentum programming cable for M1

RJ45

170MCI04110

0.3 m

RS485 master communication cable

RJ45

170XTS04000

–

RS485 cable connector T

DB9/RJ45(2)

170XTS04100

–

RS485 T junction cable connector

RJ45

170XTS04200

–

RS485 multi master shunt plug

RJ45