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Hi Glen,
I can't find a real question from you - no matter ...
I would say that I'm very familiar especially with Siemens-PLC's - I'm working with it the last 35 years ... so if I could help you ...?
Independant : there is a very good PLC-Forum in Germany (www.SPS-Forum.de) where you can ask questions (normally in German but English is also possible) which I would recommend to you ...
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Hi,
Sorry about that don't really have any questions yet, before I open the box I kinda like to know I have access to someone who might know enough to help me shut the box. A pre-emptive cry for help if you like. There are issues that need sorting that aren't directly software linked (like a sensor going into error constantly, the patch cable had come out!). I was more after someone I could ask if my Ladder Logic was correct. It seems from the way it's set up, it won't need as much alteration as I thought. One line going a speed when called via a push button, another line going the opposite way when called by a button and a roller table non-powered between them. At the moment it looks like we can just flatten the square and go from there with no alteration (until the ammount of room is changed so we either need to lengthen it or shorten it)
Thanks
Glenn 
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So let's make it short ... if you have any specific questions feel free to ask me - or do it inside the Forum I suggested to you (where I am one of the Moderators).
Independant - I'm quite sure that you could be helped to solve your issue ... but for that it's necessary to habe the relevant source-code.
But some question from me :
- which kind of Siemens-SW are you using ?
- is that code written in Step7-Classic or TIA ?
- do you know that normally you could switch from Ladder (KOP) to Instructions-List (AWL - sorry I only know the German words) or Function-Plan (FUP)
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I think we are using TIA version 17... if that makes sense, the ladder appears inside funtion blocks (which confused me!) I will get over to the Forum you suggested, I know the registering process can take a little time.
The source code is a collection of three files (does that sound right?). I'm having to pick up a project that got part done, then Covid happened and the guilty party (person that had all the knowledge) left!
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glennPattonWork3 wrote: the ladder appears inside function blocks (which confused me!)
It's actually pretty cool and very functional (pardon the pun). It's been like this for decades so Siemens was actually ahead of the curve compared to many PLCs. Here are a few basics that might help.
OB1 is the "main" cyclic function that loops endlessly.
OB100 is a "first scan" function that runs one time at PLC power-on before OB1 starts looping.
OB## are interrupt functions that only occur when a fault occurs (hardware or software).
FC## are functions with inputs and outputs but no internal storage
FB## are functions with inputs, outputs and internal persistent storage (called STATS)
DB## are data blocks that maintain persistent storage. Every FB call requires an associated DB but DBs can also stand alone.
With "Multi-Instance" calls you can call an FB multiple times. Each instance has it's own unique inputs, outputs and DB (persistent storage). Think of it as a class in C++.
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I can help you out with that, Glenn. I am maybe not as good as Ralf aobve, but I am pretty good too. Give me a PM here and I will answer you per mail, where we can continue writing or arrange a live conversation
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
modified 22-Mar-24 2:57am.
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Hi,
Thanks for that, I was having a minor panic attack! I have been billed as an expert, I am not, I have used Allen-Bradley (strangely while I was doing a contract at Siemens). Before that a course at college too long ago.
I have access to experts Yayy CP!
Glenn
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I even tried a time ago to open a section about it in the forums, articles. But there was not a big resonance and I dropped the idea.
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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My advise is to find out how it's supposed to work, then get a Click PLC from Automation Direct and re-implement it.
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You can email me. In engineering, it is a very common programming standard, along with other standard you would be more familiar with. It can be converted to a more procedural style with fancy Allen-Bradley tooling, modified, then converted back. You usually want a systems integrator to do it, because you’re running equipment. Give me a shout. pjschieck@aol.com
Pete Schieck
Legal/business refs:
build-a-concert.com/legal
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Cheers, the issue is I have do a bit a college many moons ago. I remember enough to be dangerous. Didn't know anyone in address my book, I know VHDL, C, C++, C#, Java, VB not ladder! 
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The coolest tip I can give to a C programmer would be that 110V is on one side of the ladder, and NEUTRAL is the other side. Each step (rung) of the ladder is a Boolean switch (or multiple) to turn ON a light. FYI: Rockwell inspection rungs are different than standard Boolean logic, so it can be tricky. But, with your procedural knowledge, it just takes a bit of converting bools to electrical ‘switches.’ PLCs (the controller) are simply arrays of Boolean-mapped (as in truth tables) relays in an electrical panel … really, really small relays.
I always have to take a refresher video when I convert, as I program in C and ladder.
Typical Rockwell ladder rung:
If (on the left side of the ladder rung) the switch is closed (e.g. light switch)… then complete the circuit to the light circuit, which is represented as a COIL on the right of the rung. Execution order (PLC ‘scan’) is top-to-bottom of rungs. Rockwell uses ‘tasks’ to break ladders into logical sections.
Good luck. Rockwell is the best.
- Pete
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Alien: Romulus | Teaser Trailer - YouTube[^]
In two minds on this one - the trailer looks good, but lacks any sense of a story going on. I'll probably wait till it's streaming rather than go to a cinema.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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For me it's Alien (a horror film in outta space) & Aliens (A war movie in the style of Zulu) Alien3 and on are not worth a Cinema ticket in my view.
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I agree
"A little time, a little trouble, your better day"
Badfinger
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Too scary for me 
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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OriginalGriff wrote: Romulus
Given the name, I was expecting another Star Trek movie/show. 
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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or Ridley Scott still on a Roman vibe with a sequel called Remus.
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So, a follow-up to Star Trek: Nemesis[^] then?
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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I'm quite a fan of the Alien/Predator/Prometheus movies. Prey didn't have much of a story either but I still enjoyed it.
Hopefully this adds a bit more to the AvP universe.
// TODO: Insert something here Top ten reasons why I'm lazy
1.
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Mind you just thinking about, the ship in Prometheus was the original design for the bridge in Alien, just cost too much money to build so they went for lots of small light bulbs and industrial look. Which to my mind is how it should look, container ships look that way as they are functional rather than pretty. Which follows my mantra of Pretty's nice, ugly works!
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Until a light on an all-black panel lights up black...
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Dang, the target users were not Voguns or have a lack of taste, so black on black not sure an issue!
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but I stand corrected.
"A little time, a little trouble, your better day"
Badfinger
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Not sure if this counts as a programming question, since I'm not asking for code but rather preference. I'm in a project that requires complete accuracy on numbers. So, given the following...
We all know the famous of examples of stuff like this:
0.1 + 0.2
Up until now, I've been content with rounding off any operations after the fact and calling it a day, as close enough was good enough. For applications, say that deal with currency, the age old trick is to just use integers based on a cent value. So, a $1.23 would be stored as 123 in a variable. Sweet, but, consider this:
12345 / 225
If I move along powers of the base, I never run into issues. But for your typical run of the mill calculations, even with integers, you still have to deal with fractional floating points in the arithmetic.
So, I've been using integers and rounding off any calculations to their nearest integer value. Maybe sometimes I'll floor or ceil depending on context, but that's been my current solution, which is a lot more accurate but not 100% accurate. But, good enough-ish.
Soooo....
1) You guys prefer using a library to handle stuff like this? IMO I don't use one for arithmetic because most libraries for this (at least in JavaScript) are clunky and slow and don't really do a better job anyway.
2) You think integers and rounding is also the way to go? Keeps crap simple and all that, despite needing to remember to always round after division calculations or calculations against fractional types.
3) Never do arithmetic? Tell the user to go home.
Jeremy Falcon
modified 20-Mar-24 22:18pm.
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