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

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

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

(OP)
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 exemple, 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 succes, i have the same issue.  

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

Start by sending this question to the support people for the power analyzer. It is up to them as to how/if to support "Real" values on the RTU protocol, generally they are 32bits long, and do not fit in the 16bit 4xxxxx registers.  

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