managed to write my first "program"

I just finished writing my first program! Well PLC program anyway.

I used to do a little programming when I was a kid working thru manuals on my old computers. (TI994a and then Atari1200XE) Have I dated myself?

In high school I took every programming course they had and aced them all, even though my smart but ADD addled brain caused me to "just get by" in other classes. (C's and B's were doable with no effort so why not)

Got married young and went to work right out of high school. I was able to do a little programming at my first job, but after 4 years they closed down and I went to work at a factory where I would spend the next 24 years. I did go to college in the middle of that tenure and got a degree in Data Communications. I had planned a career change, but I couldnt afford the pay cut.

A few years ago things changed at the old factory, and I had to look elsewhere. I wound up working as a maintenance tech in a different industry.

I made their top grade this last year, and have learned a lot. We have controls positions there, but there is not much turnover. Still, Ive been wanting to move in that direction. We are expected to be proficient in multiple disciplines, and I am.

I wanted to do something on my own to try and learn. I learn best when I can get my hands on something and pick it apart. I scoured Ebay and managed to make a test rack of sorts using an SLC500. I got a hold of some software and got to the point where I can make things happen.

So far, I have a red light, an air solenoid and a prox.
My first program lights the lamp when the prox is triggered, counts the trigger, after 5 triggers it energizes the solenoid thru a relay, holds it on for 5 seconds (during which time it effectively ignores further prox triggers) then releases, then starts counting prox triggers again.

Sounds simple, but it put a big smile on my face! Best part was working out the bugs along the way, trying to make it do what I wanted it to.

I want to add some more inputs and outputs, and just make nonsense here on my bench. Just for fun.

Cheers!

My hat off to you sir, I think you've got the spirit to learn and find things out on your own. That in and by itself is in my view one of the most important skills one can have in this business as you will keep running into things you don't know and will have to find solutions for. Keep going and ask if you get stuck.

better late said:

Sounds simple, but it put a big smile on my face!

Click to expand...

Thats one of the best ways to learn... have someone give you a 'end result' what they are looking for, then you make it happen

Most of the time in the real world the management will ask you to modify/build a machine and all they will say is "I need this to happen when this happens" and now its up to you to figure out what is needed and how to make it happen

If you want list the I/O you have and we can give you a project to make happen

So far, I have a red light, an air solenoid and a prox.

Click to expand...

Do you have any switches for inputs wired up?

Congratulations!

Sooner or later an opportunity will come up at your plant to make some modifications to some piece of equipment. You've put yourself in a position to be the person able make those changes, and also to recognize the opportunity when it presents itself, so you can tell the boss you'd like to be the one to do it.

PLC Class

Check out the 'PLC Class Outline' at www.corsairhmi.com
It's a free anonymous download. No advertising.
It's not brand specific - the key is to learn the programming theory as it applies to PLCs.

I was fortunate - I got into PLCs when the first CPU dropped under $1000.00 and the market exploded. I went through the first Ethernet CPUs under $1000.00 and the market kept exploding. Now that there are so many people doing the work I sometimes wonder if the average programming skill set of those in the industry has declined. I'm concerned about a lock of attention to the fundamentals.

Work hard, be diligent, and you'll do well.

Congratulations! on your first steps to what could be a long and rewarding career

Excellent. If you are interested, you could post your program here (e.g. screenshot or PDF) and get feedback. The are often alternate paths to equivalent behavior.


I find the programming straightforward (although I am not good at it); if you ever figure out how to teach yourself hardware configuration and the like without spending of order 10k$ per OEM, let us know!

Congrats,

may i suggest the following.
get with your boss and tell him you are interested in the controls position and you want to learn more, this will give him an incentive for additional help when plc's go down.
find a machine in your plant that you want to study.
see if you can find any manuals and prints.
watch the machine operate and take notes.
ask the operator the sequence of operations.
then look at the plc program and see if you can see how the system is programmed. NOTE ! the code in the pc may not be the actual code in the plc. things get changed without notice by others. i would not connect to the plc, just look at the code you have.

hope this helps,
james

Nice Work!

My first program was with a click plc and a solenoid operated hydraulic valve from northern tool. I took the double detent valve off my logsplitter and "automated" it with the PLC and solenoid valve.

I smoked (welded) two of the relay outs on the click PLC. At the time I didn't realize that there was low current limit on the relay outs. So yeah there's that!

For me the only way to learn is to have motion, speed and variables. Trainer Lights cant crash... Pneumatic cylinders are quite simple in function. Some of the trainers on the market don't really teach you much about real world applications, they basically show you how to program some basic lines in ladder.

For the motion portion, you need to consider multiple assemblies at once and the potential for crashes, we call them "unplanned interference". Setup up simple cylinders with end effectors that can crash and think though how best to prevent it.

For the speed... Stopping boxes at 60 FPM is easy, 200FPM is not so easy. The simple speed change could make your whole program for the 60 FPM conveyor invalid. What happens when you have a jam at 200 FPM?

For the variables... If I write a test program for a 12x12 box on a conveyor with a divert and it works well what happens when I place a 16x12 box on it? What happens when there is a jam, what happens if an operator flags a counter eye? Etc... The variables will always exist, it is your job to program through all the ones that you can think of. Then, go back 6 months later and program all the ones that you didn't think of.

Stick with it, the successful ones are successful because they are to stubborn to quit.

better late said:

I
I used to do a little programming when I was a kid working thru manuals on my old computers. (TI994a and then Atari1200XE) Have I dated myself?

Click to expand...

TI-99/4a? Oh dear, that does date you (and me ).


I wrote a program to do my taxes on it once, and another program drew Lissajous curves on the screen.

something else you will need to do,
look at the i/o specifications, output life expectancy, current limits.
do the inputs require a sinking or sourcing input?
are the outputs sinking or sourcing?
different manufacturers use different terminalogy for i/o, so you need too be double sure.
lots of things to learn, just one step at a time.
james

Congratulations!
I see that you said that it is a SLC500
Tell us more.
What processor, what cards are in the Rack?