LAUREL LTS, Owner'S Manual

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12. USING DIAGNOSTIC TOOL QMODMASTER
1. ABOUT QMODMASTER
qModMaster.exe is a freeware Windows program which allows a PC to serve as a Modbus
Master. It is an easy-to-use tool to verify communications, send requests to Modbus Slaves,
and view their responses. qModMaster works well with Base 0, but not with Base 1, so use it
only with Base 0 and subtract 1 from the Register addresses listed in our Modbus Manual for
Counters. For more information, see the qModMaster section of our Modbus Manual for
Counters at
https://www.laurels.com/downloadfiles/Modbus-Manual-CTR.pdf .
Download qModMaster from SourceForge at:
https://sourceforge.net/projects/qmodmaster/files/latest/download
Click on the downloaded file and install it in a directory of your choice. Create a desktop icon
from the installed executable. Before using qModMaster, ensure that your LTSE transmitter
has been set to Modbus RTU as explained in the Instrument Setup (IS) software section of this
manual.
2. EXAMPLE: USE MODBUS COMMANDS TO OUTPUT 4, 12 OR 20 MA
The task is to configure qModMaster to generate analog outputs of 4, 12 and 20 mA. This
assumes that Instrument Setup (IS) software has already been used to set up the analog
output as 4-20 mA with an Item 3 Lo Range Reading (for 0 mA) of +000000 and an Item 3 Hi
Range Reading (for 20 mA) of +010000. These decimal values of 0, 5000 and 10000 form 32
bit hex values of 0000 0000, 0000 1388 and 0000 2710.
Launch qModMaster. A screen of the type shown below will appears. Under View , press Bus
Monitor
. Under
Options
, make the selections illustrated below. The entered serial port should
be the number assigned by Windows Device Manager.