adccommunitymod (AutomationDirect) asked a question.
Modbus bit order
Created Date: September 24,2017
Created By: ozichris
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I have a DL06 connected to a water meter on a serial 232 Modbus network. I'm reading total and flow rate, floating point 32 bit values. The meter sends the MSB first, I thinking this is being written as LSB in PLC. I have read of this before but can't find the reference. Looking for some help.
Created Date: September 24,2017
Created by: ozichris
I have a DL06 connected to a water meter on a serial 232 Modbus network. I'm reading total and flow rate, floating point 32 bit values. The meter sends the MSB first, I thinking this is being written as LSB in PLC. I have read of this before but can't find the reference. Looking for some help.
Created Date: September 25,2017
Created by: bcarlton
To understand this type of confusion I refer to of the online 'floating point calculators '. Type in the hex values you are receiving. If needed swap them around until you see an expected value. It should help you understand what you will have to do in the PLC to get usable values.
Created Date: October 14,2017
Created by: ozichris
Thank-you, I managed to work it out like you suggested. Had to swap the words in the PLC and worked.