[?]: Analog input 0-24 mA

[Ilija28]

Hi. I need to read analog input from NH3 sensor !!
The output is 0-24 mA, and the range of sensor is 0-14 mg/l
I need to do this with step7 v5.4,and it MUST be with LADDER logic !!!
After that, i need to display the results in wincc panel !
I just need to program this,its a faculty project !
I do not need to simulate step7 and wincc,
i just need panel to simulate numbers between 0 - 14 mg/l .
Have anybody idea how to do this with Ladder logic in step7 v.5.4 sp1 and wincc flexible 2007 !!

In previous letter i made mistake,the sensor output is 4 - 20 mA,dont 0 - 24 mV !!!!
It was writing mistake.
Sorry !!!

[CoMod]

Add Input to Symbol Table

Code: Select all

MyAnalogInput PIW 300 INT // Integer !

Add Variable Table to your programm and insert this input.
Normal range for Analog input INT 0...27768
For convert to Real value (for example 0.0...14.0 mg) need use FC105 Scale

See Manuals with usefull examples, pictures and photos

SM331; AI 8x12 Bit Getting Started part 1: 4 -20mA
SM331;AI 8x12 Bit Getting Started Part 2: Voltage and PT100
SM331; AI 8 x 12 Bit Getting Started part 3: Thermocouples
http://support.automation.siemens.com/W ... 166/133300

Russian
http://www.automation-drives.ru/as/down ... 20mA_r.pdf
http://www.automation-drives.ru/as/down ... T100_r.pdf