filler help

this might be to extensive for help on here but i am going to give it a shot, hopefully it doesnt get to confusing, which it probably will.

I have a bucket filler, capable of filling two buckets at once, each bucket has its own scale. the scale used to measure the weights has 4 setpoints to control four outputs per scale. there is also a three way valve before the fill valves to direct the flow of liquid.

theory of operation:

operator places bucket on scale one (sp-1), main valve opens, three way valve directs full flow to that side.

operator places second bucket on scale two, once scale one has reached a certain weight (sp-2) it not only opens the main fill on scale two but also shifts the three way valve to a center position alowing flow to both fill valves.

once scale one has reached another set point it closes the main fill (sp-3) and opens a trim valve to acheive the most accurate weight, once the desired weight is reached (sp-4) on scale one the three way valve shuts that side off completely and finishes scale 2 in the same fashion.


sp-1 weight of bucket, start filling
sp-2 certain weight allow second scale to fill
sp-3 shut off main fill on scale one, open trim
sp-4 total weight achieved, allow 3 way valve full flow to scale 2.

sp-5, sp-6, sp-7, sp-8 are the same on scale 2.

these two need to work together as well as manipulate the three way valve in order to fill both buckets at once.

i am using logix 500, with a micrologix 1000 processor.

this is a prime example of why you back up programs no matter how old your processor is or you end up in the spot that i am in.

hope this isn't too overwhelming, any responses would be great and if there isn't any i understand that as well.

thanks

And your question is...??

Is this a continuous process switching back and forth or just fill two buckets and shutdown? Do you need both automatic and manual operation? Do you need additional features such as stop and resume? What happens when a full bucket is removed and a new empty bucket is placed on the scale? How is the 3-way valve operated? Is it motor driven and are there position sensors for feedback? It might be easier to build the program using 1 bucket and 1 scale at first. After that you could add the logic for the 2nd bucket and scale. I would recommend you begin building the program, post your work in progress, and ask what you need help on.

It seems to be that your pump or filling element has not enough juice to fill both buckets maximum flow at the same time, is that correct??, you can gain production if your pump can handle more flow.

OZEE said:

And your question is...??

Click to expand...

^^

it is continuous cycle back and forth. just need automatic, i have the other process of it handled. as far as moving the full bucket and placing the empty one right now my valves bounce since my sp's are being triggered by the scale jumping due to to pushing of the bucket off. the three way valve is pneaumatically controlled. resting state is shut to one side open to the other, air to one is middle position, air to another swithces it to open other closed to the other, opposite of the resing state. i will post what i get done.
my question is how to manipulate the three way valve according to my sp's as well as not allowing my valve's to bounce when the full bucket is removed. sorry i seem to be in over my programming capabilities on this one.

Use timers and setpoint in series to de-bounce the setpoints. I'm not clear on how the three way is working. Is it no air solenoids = side 1, #1 air solenoid = both side 1 and 2, #2 air solenoid and not #1 air solenoid = side 2?

Edit:
Here is a basic example of the SetPoint 1 de-bounce in rung #1 to rung #4. Just ignore the rest.

Here is another attempt, adding the 3-way valve based on my guess for operation in my above post. I did not de-boounce the other setpoints, only the SP-1 and SP-5. Untested, just trying to present some ideas. Use at your own risk.

Just ignore the files in post #7 and #8. Here is another attempt. R2 is similar to R1 and the original combined with comments. SP-2 and SP-6 not configured yet. Untested, use at your own risk.

Thank you for your responses. I will get to try these sometime Monday morning. I will keep in touch.

i think alot of my problem is implementing timers. i know their function and how they work i have just never used them.