modbus rtu - Can't see decimals on tags - ni opc server/client


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Hi. I use labview 8.6 + dsc module.

I want to read tags from a power analyzer (ion 7650) on modbus rtu protocol. i have the register map of the device. I configured ni opc server and tags needed. The problem is that i don't know how to read the entire value from register. For example, U12 is 217.45 Volts. My tag is configured to read a word (16bit) register, but the value that i see with opc client is just 217. I can't see decimals. If it was 21745, then it was an easy job to scale that value (divide by 100).
So, how can i see decimals ? Were should i look for ?

I tried to read the next register, but it is 0.
I tried to format the register to 32bit, but no success, i have the same issue.
So far as I know, the data format, register size, and scaling depends on what options you have installed and how you configured it. Check the meter configuration options for that value.
The Modbus standard does not define the transmission for floating point numbers.

You could transfer float by several registers but that is not standard.
Different vendors may do it different.

Thus you will have to look at the documentation of your device and opc server.
I read all documentation about ion 7650...also for map register, modbus slave register....nothing about my problem.