Using 905U-D wireless modems with an Allen Bradley Micrologix 1500 PLC
Technical Application Note
Purpose
Configuring the modems
This application note provides information on using
ELPRO 905U-D Wireless Serial Modems with a
Micrologix™ 1500 Series PLC communicating DF1
protocol with Micrologix 1500 Series and SLC 5/05 PLCs.
We recommend that you read this document along with
the 905U-D Modem User Manual for details on powering
and programming the modems. This document assumes
that you have a firm understanding of programming
Rockwell® PLCs.
Configure the 905U-D modems using the 905U‑D
configuration utility. Use the standard default
configuration with the serial baud rate changed to
19200 to match the PLC. The settings should match the
following screens.
• Operating Mode: Transparent Mode
• System Address: 196
• Group Address 1: 1
• Go On-Line On Startup: Selected
• Radio tab settings:
• Data Rate: 19200
• CRC Error Checking: Disable CRC Error Checking
• Packet Size: 530
• Tx Hold-Off: 0
• Rx Hold‑Off: 0
Materials
This application uses the following materials:
•
Micrologix 1500 LRP PLC
•
SLC 5/05 PLC
•
RSLogix™ 500 programming software
•
905U-D modems
•
905U-D configuration software
•
RS‑232 DB‑9 serial cable (see “Cables” below for
pinout connections)
Cables
Use the following cable for this application.
900 MHz
DB‑9 Male
Connector
•
Serial tab settings:
• Baud Rate: 19200
• Stop Bits: 1
• Data Bits: 8
• Parity: None
• Flow Control: None
• PLC Mode: Selected
• Data Terminal Ready: Ignore DTR
• Data Carrier Detect: Only High When Connected
Serial Modem
DB‑9 Female
Connector
Radio Tab Settings
The following timer initiates a read message to the SLC
PLC.
Timer Initiating Read Message
The target device (SLC PLC) serial settings are also matched
to the 905U-D modem connected to it.
Serial Tab Settings
PLC configuration
Set Channel 1 serial settings to 19200 baud with no parity
to match the 905U-D modem. Error checking is used on the
PLC, therefore no error checking is needed for the 905U-D
modem.
Target Device Serial Settings
Channel Configuration
In this application, the SLC is used to poll 100 words from a
SLC 5/05 PLC with 905U-D modems in between.
A 1-second timer is used to initiate each poll request, as
shown below.
One-second Timer
2
Technical Application Note www.eaton.com
October 2014 www.eaton.com