7/5/2019 7:58 AM | |
Joined: 9/30/2016 Last visit: 4/5/2024 Posts: 910 Rating: (6) |
Please also see attached screenshots (I will have to make a second post because all the screenshots make too big a zip file so FCFBA and FCFBB are the 2 parts). I have a meter-counter that is unintentionally reset when the machine is switched off and on again. To try to fix this I have replaced the FC (FC12) with TEMP variables with a FB (FB12) with STAT variables instead for the meter counter logic. I have made the FB and the associated instance DB (DB23). I have checked that FC12 was s only used in OB1. I have opened OB1 and replaced the call of FC12 with a call of FB12 (including the instance DB) The meter-counter luckily still counts the meters - but unfortunately the value it has reached is still reset to 0 when the PLC is turned off and on again. Is there somewhere to set the DB values to "remanent" that I forgot? How do I make it remember "how far it has gone"? AttachmentFCFBA.zip (60 Downloads) |
7/5/2019 7:59 AM | |
Joined: 9/30/2016 Last visit: 4/5/2024 Posts: 910 Rating: (6) |
And the rest of the screenshots. AttachmentFCFBB.zip (57 Downloads) |
7/5/2019 10:54 AM | |
Joined: 5/6/2010 Last visit: 4/20/2024 Posts: 1963 Rating: (272) |
Hello xmnj, in my opinion you must not only save your result. So far I know you must save the value from the FM-450 ad must set the FM after Restart your PLC (e.g. OB100) The value from the FM-450 should you save at a extra DB which is setting retain. Please look at the manual of the FM-450.
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This contribution was helpful to1 thankful Users |
7/5/2019 11:09 AM | |
Joined: 9/30/2016 Last visit: 4/5/2024 Posts: 910 Rating: (6) |
Hello CaOd, Thank you for answering. Mostly we use Scancon encoders (https://www.scancon.dk/). When I find the FM450 manual in English I will see if I can make use of that. I CAN get through it in German but it would be a lot slower. You are probably right - but WHY do I need to have a memory in the FM-450? I want to count a number of pulses which corresponds to a number of meter. If I have the latest number of meters saved why can I not just add the new pulses (converted to meters) to the number in the memory? How / where do I set the DB (like the Instance DB for my new FB) or the values in the DB to be retained?
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7/5/2019 12:16 PM | |
Joined: 5/6/2010 Last visit: 4/20/2024 Posts: 1963 Rating: (272) |
Hello xmnj, sorry that was my mistake with the german manual. Here are the englsich manuals: SIMATIC S7-400 Counter module FM 450-1 SIMATIC STEP 7 Engineering with STEP 7 V5.x or with STEP 7 as of V11 (TIA Portal) You be right with encoder value. regards |
Last edited by: Jen_Moderator at: 07/05/2019 13:06:47Optimized links. |
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This contribution was helpful to1 thankful Users |
7/5/2019 1:00 PM | |
Joined: 9/30/2016 Last visit: 4/5/2024 Posts: 910 Rating: (6) |
Thank you again CaOd, Thanks for the links to the English manuals. We have a similar machine that has been fitted with a new control system and that looks quite different. Please see attached screeenshots ENCA.zip (this post) and ENCB.zip (next post). 2 things: 1: Why do the FM 450-1 need to know anything about how far we are? IF I have the number of meters (pulses we have run since the last reset stored somewhere I just want to start counting the NEW meters (pulses) and add this value to the value stored. What is the point of having the accumulated pulses in the FM-450-1 instead of just having this in the PLC memory somewhere? 2: WHERE/ HOW do I set the DB or DB values to be retained? I would like to do this on the instance DB I created.
AttachmentENCA.zip (50 Downloads) |
Last edited by: xmnj at: 07/05/2019 13:20:36Attachment added |
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7/5/2019 1:21 PM | |
Joined: 9/30/2016 Last visit: 4/5/2024 Posts: 910 Rating: (6) |
Remaining screenshots.
AttachmentENCB.zip (49 Downloads) |
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