LogixPro Student looking for mentors!

[mrmss]

I did some PLC programming during college and since graduating from my degree I have had no exposure to it in the three years I have been working. I have experience in other logic-type programmable controllers, more bespoke software rather than ‘off-the-shelf’ ones like RSLogix. I have wanted to learn PLC’s properly for a while and for starters have ended up buying the fabulous LogixPro PLC Simulator.

The first Lab ends with a ball-busting (to me anyway) supplemental exercise which I foolishly took on. In any case, I think I have completed the exercise and am looking for some critique.

I know I do not have the most ‘efficient’ solution and probably not the most elegant! I followed what guidance I could find on the net (not wanting to look at the answer!) and came across Lancie1’s suggestions in another thread.

It works but is still a little quirky, for example;

Door is moving and stop is pressed, door stops, pressing open or close allows door to do it’s function, however if instead you decide to press stop again – you have to press open, close or stop before the Toggle is active again!

I'd like to get the ladder as close to perfect as possible before looking at the answer in the dowloads section. My gut feeling is I may have approached this from the wrong angle at the outset and the strange stop quirk may be an inherent feature!

As the wording of the supplemental task may be slightly ambiguous, I'll try and explain my intention;

• When the door is opening and the Close button is pressed, de-energise the up winding of the motor
• When the door is closing and the Open button is pressed, de-energise the down winding of the motor
• effectively; if the motor is moving and a button is pressed for the opposing action, do the same as stop.

If anyone has any other suggestions to the toggle I'd appreciate them.

The LogixPro .rsl and a .bmp of the ladder is attached, THANKS :

 

[randylud]

I also answered in the practice section, but the program looks fine, at least the door does what it is supposed to. If it works, it can not be to bad!

 

[mrmss]

Thanks Randy, that's good to hear - I think I'll take a peak at the solutions in the downloads now.

 

[silva.foxx]

LogixPro Door simulation

Seems a little complex for a simple door. Bet it took a while. Certainly works, though.

Would you like to troubleshoot it at 3am on a cold, dark, wet morning?

Simplicate, not complicate.

Glad you showed your attempt. Good to see you using symbols and comments; very helpful.

Richie, Wrexham

 

[mrmss]

I have seen some very very neat solutions in comparison to mine. Since I did this ladder I have been looking at ways of writing PLC logic more methodically/systematically.

If I was working on a real problem and I ended up with something as messy as this do you think it's worth it to try and find ways of making the logic simpler to understand?

For example, as soon as I was satisfied that the logic did what I wanted it to do (with my ability) I breathed a sigh of releif and enjoyed opening and closing the door for a worryingly significant amount of time...but silva.foxx, did you arrive at your solution because of good initial design or because you are obviously an experienced programmer or because of tweaking after getting somewhere near the desired functionality.