Ladder Logic

[Ace1985]

Hello,

I learned a bit of PLC during my apprenticeship about 10 years ago writing in instruction format in dos on old bosch plcs. Now i'm required to work on mistubishi q-series and fx series on windows and in ladder logic.

I'm fine with the troubleshooting side of it, but editing and re-writing in ladder is stumping me a bit.

I'm spending a good hour a day now working on it, but has anyone got any tips on how to improve my ladder techniques? Any books, websites etc etc?

Thanks in advance.

 

[sams37]

Hi Ace1985
let me explain to you maybe this is can help you.
Ladder prog it's symbol like electric picture there is switch NO or NC than output at ladder is coil or timer or special fuction.
the program PLC had you studied last time it's call LIST program, at the plc software mitsubishi like GX Developer you can change to view the program at model LADDER or LIST.
if you want to know what is the meaning fuction at the ladder prog you can see help menu in the soft, there expalined everything.

 

[Ace1985]

Hi sams..

I fully understand ladder and how it works. I can fault find someone elses software with relative ease, but when I come to edit a step sequence or something, I struggle.

How can I improve/practice my editing? The easy answer is to just spend time on it, but I havent got that luxury in work at the moment. Is there anything I could do at home? Or is it a pure case of practice makes perfect?

Thanks.

 

[sams37]

Hi ace1985
maybe you can use mitsubishi FX Trainer to learn makes program Ladder without PLC.
At the software you can makes a program then you can simulated the program.
Try use this link to download the progam :

 

[tygerdawg]

This has been discussed before (search for it in these fora), and the suggestion is the same: go spend a little money and get a cheapo PLC & programming software, get some switches, wires, sensors, blah blah blah, and start creating. Blow some fuses. Make some sparks. Release some smoke. Burn some transistors. Crash a few things.

My fav is AutomationDirect. Call the expense an "investment in [your] education."

For all practical purposes, ladder logic is generic. Each manufacturer has generally the same functions, they just get implemented in programming a little differently. If you learn deeply the basic theory, it can be applied to any PLC.

And yes, practice makes perfect.

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[AgeXVII]

I was just doing this the last few weeks off and on actually. I just started at an electrical contractor firm and they hired me a EE graduate to do some of the SCADA and PLC work for them. I have only had the previous experience of looking at some ladder logic not really programming it very much but I found some helpful tools. I ended up getting my hands on a Click Koyo PLC with some input/output cards and the power supply and it was really helpful to just play with it a bit and practice to see how the different rungs and coils would react. They have free programming software which was nice to get to play and use the help files before actually getting the hardware.

I highly suggest using the help files that come with that and then it was suggested to me that if I had questions on how it worked/reacted that wasn't in the help files clearly to just program an example of that to see how it was handled.

Worked out nicely for me and I managed to get through a (7) furnace/(7) heater system running on generator mode with certain requirements!

Best of luck to you and if I can find the help files I had used as well and a good PLC book I will add it hopefully this week. I saved all of my files somewhere!

 

[AgeXVII]

Side note - That Click PLC is pretty cheap when it comes to PLC's that I have noticed and they also have little help programs to demonstrate examples that are free to download as well.

 

[redlinej]

scantime have a nice plc course

http://www.scantime.co.uk/