Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

Problems with FC105

Created by: Data viewer at: 10/24/2009 10:05 AM (2 Replies)

Rating (0)

Thanks 2

3 Entries

10/24/2009 10:05 AM	Rate (0)
Data viewer Posts: 2 Rating: (0)	Dear Friends, I need some help. my problem is, when I use simulator usign FC105, the read value (int)(Consider it in range) should be changed to value between HI_LIM and LO_LIM. the output value is not between the LOW & HIGHT LIMITS. i try several example which you can find them here too, but still have the same problem. For example: see the attached file,. there are two FC105 block with same inputs but different outputs. the left block in picture is mine. Please advise Attachment campare.JPG (218 Downloads)
Data viewer Posts: 2 Rating: (0)	Last edited by: O_Moderator at: 10/26/2009 9:37 AM new subject after splitting
Suggestion To thank Quote Answer

10/24/2009 2:24 PM	Rate (0)
fritz Diamond Expert Joined: 10/7/2005 Last visit: 11/30/2023 Posts: 2997 Rating: (1039)	Data viewer there are two FC105 block with same inputs but different outputs. the left block in picture is mine. Please advise Hello Data viewer your problem is caused by using MW0 as FC105's "RET_VAL" output parameter and MD0 as FC105's"OUT" output parameter. You need to bear in mind that S7 addressing is BYTEWISE organised which means the following in your case: MW0 is "made up" of MB0 & MB 1. MD0 is "made up" of MB0 & MB1 & MB2 & MB 3. What will happen in your case is that FC105 will properly scale the AI and write a properly formatted REAL value into the "OUT" output parameter (MD0 in your case).FC105 will then write a decimal "0" value into the"RET_VAL" output (MW0) will will corrupt the REAL value format in MD0. Please check too why you use a variable named "Motor 1 Start" for the "bipolar" input of FC105, this does not make too much sense to me. I hope this helps.
	Cheers fritz The advice and opinion given in this thread is that of the author and does not necessarily reflect the views of I S Systems Pty Limited. To find out how I S Systems can help you with your automation needs please visit www.issystems.com.au.
Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users Data viewer

10/24/2009 2:53 PM	Rate (0)
Data viewer Posts: 2 Rating: (0)	Dear fritz, Thank you for your reply. You taught me a important note. I did not know that about , since i am new user of Simatic S7. and about bipolar/unipolar: i just connected that signal to this input for testing the function. it is not very important, this program is just a test for my training. Thank you again. Farhad
Data viewer Posts: 2 Rating: (0)
Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users fritz

|

Share this page:

Share this page on...

Follow us on