Specifications

22 • XR35CX I&O Manual 026-1203 Rev 0 09-FEB-2011

17 E2 MODBUS Network Wiring

• Connect the MODBUS Network to the RS485 Connector on the E2 PIB board (Belden 8641 recommended).

• Note to wire the RS485 +/- polarity at the E2 in the reverse

of the XR35CX devices.

• Position the three termination jumpers to the UP (terminated) position to provide RS485 termination at the E2.

• Do not connect the shield of the MODBUS network to the E2 PIB center terminal. Instead, use a 100 ohm 1/2 watt

resistor to connect the MODBUS cable shield to earth ground.

• At each XR35CX device, wire the MODBUS cable to the RS485 +/- terminals and connect the MODBUS shield to

the pin 18 terminal.

• Terminate the end of the MODBUS network at the last XR35CX device on the daisy chain with the MODBUS ter-

mination block (P/N 535-2711), or by connecting a 150 ohm resistor between the MODBUS +/- terminals.

Figure 17-1 - XR35CX to E2 MODBUS Network Wiring

100 ohm

½ Watt

Shield

EARTH GROUND CONNECTION

MODBUS TERMINATION

BLOCK 535-2711 150 ohm

Terminate last device only

REVERSE POLARITY OF +/- ON RS-485

CABLE FROM E2 TO DEVICE