Subroutines: Micrologix 1500, RSLogix 500

[Merganzer]

OK folks, I've got it all figured out. Works great now. Thanks for all the help!

I'll post a piece of test code that I used. The motor stopped and started when I wanted it to.

This is a technical thesis that I am working on for my college program (Electrical Engineering Technology). If any of you are interested, I can post some things about our project so you can see it being built.

Thanks again.

 

[tomalbright]

If any of you are interested, I can post some things about our project so you can see it being built.

Ummm.. in that example you are using an input to latch an output, and another input to unlatch it.

That's a 2-rung solution, it still escapes me why you are using a subroutine.

 

[Merganzer]

Im using subroutines so I wont end up with 500+ lines of code in the main program. And then try to troubleshoot that?

 

[Merganzer]

Also, I must unlatch and latch the output bits directly otherwise they will stay in a high state indefinately. Thats what subroutines do in the Micrologix 1500.

 

[504bloke]

Also, I must unlatch and latch the output bits directly otherwise they will stay in a high state indefinately. Thats what subroutines do in the Micrologix 1500.

i dont understand your statement ?

Why will they stay high ?

Normally an output would only remain high if the preceeding logic is true.

And what do you mean by "thats what subroutines do in an ml1500" ?

 

[geniusintraining]

Dave,

Have you viewed Merganzer code?, I think it will work...He's just not done, he needs the slow speed, etc.

Thats what subroutines do in the Micrologix 1500.

I think he was refering to logix 500


But anyways finish the code, there are 100's of ways to do it...we need elevmike to help


Could you use the same speed and floor logic, just look at different floors for diferent inputs? never mind... keep going

 

[tomalbright]

I think it could be done with a lot less than 500 lines of code, but hey, everybody has a different way. "nothing is wrong if it works".

I was just commenting that with the on/off logic you had in that test snippet, there didn't seem to be much need for a subroutine to do that.

Dave, what he means is that whatever you set in a subroutine stays in that state until you execute the subroutine again.

 

[geniusintraining]

"nothing is wrong if it works"

I agree, and the best part is... if it works and never fails then I will never have to look at it in the first place , as long as that elevator stops at the correct floor.

I think it could be done with a lot less than 500 lines of code

Thats why I made the statment of never mind

 

[PLC Gremlin]

Thats what subroutines do in the Micrologix 1500

Do not condition your subroutine calls.
Just let them scan..
Condition the logic IN your subroutines.

 

[Domino2205]

you should only reference an output one time so I believe what might be happening here is it does not change to 35% because somehow your use of 60% is in the program last and the last one wins. What you could do is use a bit to deactivate your rung using the 60 cycle anytime the 35% is being used or true

 

[tom_stalcup]

you should only reference an output one time so I believe what might be happening here is it does not change to 35% because somehow your use of 60% is in the program last and the last one wins. What you could do is use a bit to deactivate your rung using the 60 cycle anytime the 35% is being used or true

That sounds correct. However, I'm going out on a limb here and say that in the last ten years since this particular thread started, Merganzer has finished his school project. Or abandoned it entirely.

This is a technical thesis that I am working on for my college program (Electrical Engineering Technology). If any of you are interested, I can post some things about our project so you can see it being built.

Thanks again.