Analog Output Mapping from Real value 32Bit to PQW word 16bit.

Hi All,

My understanding is that for Analog Input let say PIW256 for mathematical operation. First, I need to convert Integer value Double integer I_DI and then Double integer to Real. DI_R.

After mathematical calculation, result is Real number. i wanted to map this real number result to analog output say PQW256. 

Real -> double Integer -> integer -> PQWxxx (there is no option of real to integer conversion)

what conversion do i need? can someone write with example?

First you should let us know which software you use and choose correct conference. STEP 7 (TIA Portal) or  STEP 7 / STEP 7 Lite

Then we would like to know hardware you use.

Finally describe what is the meaning of this REAL number result (e.g. 50.0 means 50 Hz) and what is interpretation of analog output signal. Eg. 10V means for an inverter to run at 100 Hz.

Hello,

first of all, it's easier to give you a qualified answer if you tell us

• the version of your programming software include the the version, e.g. TIA V18 SP1 Upd 4
• the PLC what you want to use, e.g. S7-1513 or S7-314 include the firmware version or the MLFB

If you want to read a analog input you should know that you must convert and calculate the value of the input word. (NORM, SCALE)

Please have a look at this link to handle analog values: 

SIMATIC S7-1500, ET 200MP, ET 200SP, ET 200AL, ET 200pro, ET 200eco PN Analog value processing 

Convert a DINT to a INT is "easy".
You must only load the lower word of the DINT to read the INT.

If you tell us the PLC which you use, I can give to a example to do the "easy" conversion.

regards
CaOd