Then convert the REAL to DINT with some implied number of decimals for accuracy if it makes sense for your specific deal.

I have no idea how to make your specific SCADA read Siemens REAL data correctly.  I can only offer suggestions which might help.  If the SCADA is Siemens software, go to the forum supporting that software.  If the SCADA is non-Siemens, go to their support site and ask how to read S7 real data.

engco

when i read Dint it works fine, the problem happen when i real float value.

I had similar problem while communicating Siemens PLC and Bosch PLC with real values.  I tried al possible byte-word swaping and conversations available in the PLC code. End up creating my own FC.  The below link helps you understand the Float value representation in DWORD.  (Again byte swap is also important) 

https://www.h-schmidt.net/FloatConverter/IEEE754.html 

Its long time I used Indusoft. If I am not wrong we have math functions in Indusoft software. 

Wish you good luck