S7-300 with TIA Portal V13 SP1 Analog Input Output

Tyler Harvey

0-1 measuring range module is in position D

Input 0 is wired to a 4 wire device 4-20mA

%IW700 reads 16#0000 at all times

Current to input 0 is verified as non-zero

Input 0 is wired to a 4 wire device

%IW702 reads 16#0000 at all times

Current to input 1 is verified as non-zero

2-3 measuring range module is in position C

Input 2 is wired to a 2 wire device 4-20mA

%IW704 reads 16#0000 at all times

Current to input 2 is verified as non-zero

Input 3 is wired to a 2 wire device 4-20mA

%IW706 reads 16#0000 at all times

Current to input 3 is verified as non-zero

Why can I not get analog inputs into the PLC and analog outputs out of the PLC?

Hello,

Position D is for current 2 wire transducer

Position C is for current 4 wire transducer.

Please refer attached sheet. 

Tyler Harvey

0-1 measuring range module is in position D

Input 0 is wired to a 4 wire device 4-20mA

2-3 measuring range module is in position C

Input 2 is wired to a 2 wire device 4-20mA

 Hello Tyler

I think you have inverted the measuring module, Please go to chapter 4.2.4, 

S7-300 SM331; AI 8x12 Bit Getting Started part 1: 4 -20mA

Hello,

if you work with %IW and %QW you work with the process image.

In a S7-300 the process image size default is 128 bytes.

So the adress 700 and 800 outside the default process image of the plc and can't be accessed with %IW and %QW.

Check that the processimage size is > 800, you can configure this in the properties of the PLC.

If you wouldn't work with the process image acces the you can use the peripherie direct access.

In the  old Step7 V5 you use the syntax PQW and PIW.

In TIA you must use the Syntax QW<adress>:P and IW<adress>:P

Regards

Christoph