Allen-Bradley 857-RAA, User Manual

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Rockwell Automation Publication 857-UM002C-EN-P - February 2018 21
Configure the Base 857 Relay Chapter 4
Connect to the 857-RAD RTD
Scanner The 857-RAD enhanced RTD scanner communicates to the base relay using a
Modbus protocol over dual fiber optic cables. The address of the module must
be set with the DIP switches on the side of the device. The available address
range is 1…247. See the side and top of the 837-RAD enclosure for switch
position (
Figure 3 ). The baud rate is fixed at 9600 bps, with even parity.
Protocol Configuration for 857-RAD RTD Scanner
1. Select Protocol Configuration in SetPointPS.
2. In the Remote port protocol section, confirm ExternalIO is selected.
3. If it is not, click the pulldown menu and select ExternalIO.
IMPORTANT The unit Bulletin 857 relay must be equipped with a dual-channel optical
interface module (VCM FIBER) to receive data from the module.