9/27/2015 5:35 AM | |
Posts: 6 Rating: (0) |
Dear expert, I am new Siemens programmer. hope you guys can help me with this problems. I have a light-sensor circuit with the out put voltage is 0-24V. I want to use analog modul AI 8x13bit 413-1kf00-0ab0 (s7-400) to read this value using LAD programing. Th goal is using this circuit to control light system in green house. I have try with PIW and FC105 scale but it seem that I dont know how to use them. Can any one help me to resolve this issue, or giving me some examples similar to this? Best regards. Ted ------------------------------------------------------------------------------------------ |
Last edited by: Min_Moderator at: 9/28/2015 4:51:34 PMNew subject after splitting |
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10/1/2015 7:01 AM | |
Joined: 1/28/2009 Last visit: 9/10/2024 Posts: 6849 Rating: (1365)
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Hello ,
First you should be sure that the analog input value in PIW512 is stable and has linear relation with engineering values.You can check that by varying input signal (voltage/current) and see the converted value in HW Config (right click on module-->Monitor modify). If converted value in STEP 7 is not stable or shows wrong values, you need to consult THIS manual. If your PIW512 has stable values and corresponds with the physical values , possibly you are using a wrong MDxx.This is possible when an overlap happens in case of using wrong double word selection in your program.As an example using MD10 and MD12 as floating point for 2 varying applications may lead to such an error.Reference data is your help to point out the error. hdhosseini |
Last edited by: hdhosseini at: 10/1/2015 7:03:13 AM |
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This contribution was helpful to1 thankful Users |
10/1/2015 11:52 AM | |
Joined: 3/5/2014 Last visit: 8/5/2022 Posts: 5521 Rating: (1054) |
hi Ted, The variables are suitable too, but MW100 is a content of MD100. MW100 and MW102 are MD100. see the picture in this FAQ Inside the scale function MD100 is written before the retval is written. And with your constellation you are overwriting a content of MD100 with the RET_VAL value on MW100. regards, |
Last edited by: mopS04 at: 10/1/2015 11:57:37 AMchange link FCK WAR! |
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