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11.3 Troubleshooting Issues
Problem
Solution
Communication contention between
the LCD and process
The LCD and the processor applications share the external Modbus connection. If the processor is configured to
constantly interact with Modbus, it may cause issues with the LCD attempting to use the functions of the ISM radio.
To alleviate the contention do one of these things:
•
Load a DXM configuration file that slows down the read/write rules.
•
Disable the DXM configuration file from loading into the processor by setting DIP switch 4 to ON (on the
processor board). Reboot the device. When the processor reboots, it will not load the configuration file
and remains idle.
Cellular modem did not turn on
If the incoming voltage drops below 11.2 V dc, the cellular modem does not turn on and will not turn on until the
voltage is above 11.8 V dc. A text file (CmVMon.txt) on the internal micro SD card saves the periodic sampling of
the incoming voltage. If cellular operation stops because of voltage, it is logged in this file.
11.4 Modbus Operation
All Modbus transactions are managed by a central Modbus engine. If there are Modbus messages intended for a Modbus
slave that doesn't exist, the Modbus engine waits for a response until the timeout period is expired. This slows down the
Modbus polling loop for read and write operations.
For this reason, verify all Modbus read and write operations are intended for Modbus slave devices that are in the network. If
a Modbus slave is not in the network, either a wired or wireless device, the operation of the LCD menu system can be
compromised. Operations like Binding, Site Survey, or accessing the ISM menu may be slower. This is because all internal
devices (such as the ISM radio, LCD, etc) of the DXM are also Modbus slaves.
Sure Cross
®
DXM150 and 1500-Bx Wireless Controllers
www.bannerengineering.com - Tel: + 1 888 373 6767
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