Stuck Technology student!!

[Ivy K]

Ivy the newbie

Wow, its been a couple of days and I thought that I might have a peek at my old HELP!!! post and I must admit, a bunch of you guys are truley PLC gurus. A fellow student and myself did manage to iron out our little pushbutton wrinkle this week but thanks for all the insight guys!!!(even if I dont have a clue about most of the things being debated). I'll toss' it up there for y'all at Whistler tommorow.

 

[zmanvortex]

What if the operator had a little too much coffee to drink that morning and his hand action caused the process to start and stop before he even knew what happened.

What I do is create virtual push buttons.

If the operator pushes the button it sets a "On push button" bit(which you could use in your program as a separate On push button) and starts a timer.

If the operator pushes the button again before the timer expires, nothing happens.

If the operator pushes the button after the timer expires it sets the "Off push button bit" and starts another timer.

You could then use the "On Push Button" and the "Off Push Button" bits in your one shots as if they were two separate Push buttons, hence "virtual buttons".

 

[Jezz]

I love this trick of using one push button to toggle a Bit on and off its saved me a lot of time recently, no longer do I have to drill a hole in the front of the panel and add a new push button(and in some cases even a new input card ).Ohhh the power of softwire over hardwire.

Just my 2 cent's worth

Jezz

 

[emersalvador]

the first rung shld. have an OSR(for AB)this is a pulse signal only bec if you dont place this one you will have an on-off state or no reaction at all if your input is always turned on




|Input 1 Internal 1
|--] [-----------------(OSR)---------------------------------( )--
|
|
|
|Internal 1 Output1 Out 1
|--] [--------]/[-----------------------------------------( )--
| |
|Out 1 Internal 1 |
|--] [--------]/[------|

 

[Eric Nelson]

And this is different than Mad's post is what way?...

beerchug

-Eric

 

[rsdoran]

emersalvador
When making the ladder diagrams be sure to put code inside brackets [ ] at the start and /code inside brackets [ ] at the end

|Input 1                                                Internal 1 
|--] [-----------------(OSR)---------------------------------( )-- 
| 
| 
| 
|Internal 1 Output1                                      Out 1 
|--] [--------]/[-----------------------------------------( )-- 
|                      | 
|Out 1    Internal 1   | 
|--] [--------]/[------|

Technically Eric this is MY BAD POST with the OSR added.
Using GE format my post should have been like this:

|Input 1                                              Internal 1 
|--] [---------------------------------------------------(^)-- 
| 
| 
| 
|Internal 1 Output1                                      Out 1 
|--] [--------]/[-----------------------------------------( )-- 
|                      | 
|Out 1    Internal 1   | 
|--] [--------]/[------|

The (^) represents a positive transition coil which is the same as a One Shot. It seems the key to this is using a One Shot which only works for one scan. I know you know this but I am stating it for those that dont know and myself to penetrate the dense matter that fills my head.

 

[emersalvador]

rsdoran,
i forgot to place codes anyway thanks for the reminder