Corporation Network Adapter Product Manual

WIRING THE MODBUS CARD

EATON Powerware

Modbus

Card User’s Guide S 164201376 Rev C www.powerware.com

For four-wire networks. All four RS-485 network signals including TxD(+),

RxD(+), TxD(–), and RxD(–) must be connected to the terminal strip as

illustrated in Table 1. Verify that the Modbus Card J9 and J10 jumpers

are set to the four-wire option (see “Four-Wire Communication” on

page 4).

TxD+ RxD+ TxD– RxD– GND

12345

Figure 8. RS-485 Terminal Strip

Table 1. RS-485 Terminal Strip Pin Assignments

Pin Number Modbus Card Signal Name

RS-485 Network Signals

Master Signal Name

1 TxD(+) RxD(+)

2 RxD(+) TxD(+)

3 TxD(–) RxD(–)

4 RxD(–) TxD(–)

5 Signal common Signal common

RS-485 Modbus Port

For two-wire networks. Connect the RS-485 network signal TxD(+) to the

Modbus RxD(+) input signal (DB -9 Pin 1). Connect the RS-485 network

signal TxD(–) to the Modbus RxD(–) input signal (DB-9 Pin 6). The

Modbus Card factory-default jumper setting for J9 and J10 is two-wire

communication.

For four-wire networks. All four RS-485 network signals including TxD(+),

RxD(+), TxD(–), and RxD(–) must be connected to the pin assignments

on the DB-9 connector as illustrated in Table 2. Verify that the Modbus

Card J9 and J10 jumpers are set to the four-wire option (see “Four-Wire

Communication” on page 4).