What to call it.

[John Morris]

Good morning Gentlemen.

RS Logix micro developer, FTV, and 1400 A processors

The process Is...eleven linear tanks performing various tasks, (wash, rinse, passivization, sonic), some tanks we do not want to use on certain products. Skip tank. some just two, some nine.

I am trying to find examples of this type of programming, but not having any luck searching "batching" or "recipes". I have tried "menu processing" and several other variables with no luck.

I would appreciate a point in the right direction.

Thank you for your time.

 

[OkiePC]

This sounds like a sequence. I am not sure that a classic "sequencer" or "drum stepper" is the right approach to programming it though. But those are some search terms you might try to get some design ideas.

By linear, I suppose that means arranged in a line or in a fixed order as far as processing goes?

What do you have for an operator interface in order to select and make adjustments to the sequences or "recipes"?

How does the system determine (or get told) which recipe to use at a given time?

 

[John Morris]

That is correct sir they are arranged in a line and the order is fixed.

Anything helps.

Thank you Okie

 

[James Mcquade]

John,

From your description, the processes are in line and follow each other like a walking beam.

If that is the case, I would set up a binary word file and move the data from word to word. Each word would contain the binary bits for each station. Leave bit 0 blank, that would be station 0 (load station) and bit 15 (sign bit).
that gives you room for 14 stations.

For example B3:0 would be the part at the load station and lets say you do not want the part to run at station 4, but run at all the other stations. Go into the word and type in the binary number of "1" for all stations except bit 0 (load station) and bit 4. You would have 0000111111101110 or 4078 in that word.

When the part moves from the load station to station 1, move that word to b3:1 and in the logic for that station, look for bit B3:1/1 being on. If it is, run station 1 logic, if its off, skip the station.

repeat for the remaining stations.

regards,
james

 

[John Morris]

James, your deductions are correct.

Since there is possibility of 11 baskets on the line at one time and any combination of four recipes, I have to transfer the recipe for each basket from PLC (first three) to PLC (next four) to PLC (last four). Is it possible to create this as a global instruction (word). Would it work the same way.

Thank you James, Your description made it very easy to understand.

 

[James Mcquade]

John,

What are the brands and model numbers of the plc's being used?
james

 

[John Morris]

Allen Bradley Micro logix 1400A

 

[John Morris]

Sorry sorry

My bad

1400 series B

 

[James Mcquade]

John,

I talked with my co-worker and the ml1400 can do messaging (please verify).
I would buy a managed hub and connect all 3 units together using different ip addresses and do messaging between the plc's with a heartbeat signal and message block data verification. You will also need a strobe light and alarm horn in case there is a problem to let the operator know of trouble. A hmi terminal would also be useful to see the transferred data and allow you to correct the issue.

You will have to think this thru for your application.

regards,
james

 

[OkiePC]

Can there be eleven different batches being processed at any given time? I am assuming you do not have just one batch that ties up all eleven stations until it is done, but multiple batches in process.

What about user interface? Are these recipes going to be fixed in the PLC and inaccessible or will there be a touchscreen or PC involved to allow operator intervention and adjustments?

The ML1400 can message each other over Ethernet or either of two serial ports. Are they already sharing an ethernet network?

 

[John Morris]

Hi James, Okie

Thank you for giving attention to this.

It has an HMI and it communicates to all four processors VIA ethernet and switch

There will be three standard recipes and the fourth one the operator will be able to customize.

My concern was if I have 11 baskets on the line and four different recipes, how do I manage the count and not loose the track.

Don't mind telling you, I'm in just over my head.

I know I can make the button on the HMI give it the recipe word (as James suggested, thank you for that.) and send it to the first PLC. I can write a msg and have it sent out. After that I got nothin.

All the work is done in the 2,3, and 4 PLC. 1 works the transfer and the manages the HMI interface.

It's a long story on how I got to this point. How I can do one, but not the other.
I do know enough to know, I don't know enough. Quite frustrating actually

Just to let you know, (try not to laugh) after I figure this out, I have to data log ten parameters per/by basket.

I read up on the data logging, I think it was Okie who pointed me to the link even (TY2), I get the structure and how its supposed to work, just don't know how to attach it to the basket number, log all the tanks, wrap it up in a packet. and store it for a minimum three days before it overwrites.

I miss drinking.

Gents, I'll find the words one day to express how much I appreciate you sharing this information with me. And, if I ever get to a point where I understand better I'll pay it forward (god help them)

Thank you

 

[danatomega]

You are saying that PLC #1 handles the transfer to the various operations?
Then I would allocate space for the recipe on a per-basket basis - 11 baskets = 11 recipe spaces.
Recipe gets copied from the master recipe to the basket recipe so it rides along with the basket transfer.
I assume (sorry) that you can shift the data from one 'station' to the next without issue? Using shift register style programming?
You may need to have load & unload recipe holes also.

It sounds like the transfer would actually handle the decision whether to put a basket into a process, so doing it this way makes sense to me.

Finally, the unloading would move the recipe data (or results) into a fifo stack for your 3 day storage.

 

[John Morris]

Ill have to check and see if the data shift is there. I'm not entirely sure.I know when the basket is put to the load station it starts the sequence. When the walking beam travels home it triggers a stage shift, the next tank drops and starts the timer. I'll have to find that transfer bit that goes from one stage to the next and use it to trigger the recipe transfer. You said register to register move function. Correct.

I think I can put one of those together.

Ill start at the HMI with the four buttons, do an enter (move) function to the Master PLC, ( if that's what it's called ) these entries would go in single file correct, then as each is moved to the first stage I can use the trigger tank shift off the walking beam to also shift the basket registers.

When a shift is done does that leave the existing register emptied or is it just copied over when the next set arrives.

What if ( sorry guys ) the operator enters the wrong basket recipe. Its a ten minute sequence so there's no big hurry, but if he sets it in the load stage with thirty seconds and pushed two when it should have been three, how do you go about backing out of that. Assuming the msg is sent when the walking beam starts (shift left, arms down shift right , back two inches, arms up) on the shift left it sees the prox and shifts the register. would pushing the two button overwrite the loaded three button.

Hell could go on for days with questions.

Ill see if I can get the first section done> HMI to PLC 1, to PLC two Stage one. go from there.

THank you for your insight Danatomega.

 

[danatomega]

When the walking beam travels home it triggers a stage shift, the next tank drops and starts the timer. I'll have to find that transfer bit that goes from one stage to the next and use it to trigger the recipe transfer. You said register to register move function. Correct.

Yes, using a MOV. Or, if the recipe is large, several MOV's may be required.

Ill start at the HMI with the four buttons, do an enter (move) function to the Master PLC, ( if that's what it's called )

Earlier you referred to it as the transfer but call it what you want. You could transfer the recipe on button push or just the recipe number and wait for the first shift to actually copy the recipe. Either way would likely work.

these entries would go in single file correct, then as each is moved to the first stage I can use the trigger tank shift off the walking beam to also shift the basket registers.

Yes, the recipe would go into the Basket #1 registers.

When a shift is done does that leave the existing register emptied or is it just copied over when the next set arrives.

I would leave it with the previous data and just overwrite it when the next set arrives.

What if ( sorry guys ) the operator enters the wrong basket recipe. Its a ten minute sequence so there's no big hurry, but if he sets it in the load stage with thirty seconds and pushed two when it should have been three, how do you go about backing out of that.

I would just overwrite it - operator could push 1 - 3 - 1 - 2 - 4 and it would be okay.

would pushing the two button overwrite the loaded three button.

yes

Hell could go on for days with questions.

you certainly will have more questions - this is a fairly large undertaking.

 

[John Morris]

Thanks for the validation.

I thought I was just being whiney.

I can thank you all enough for helping me get to this point.

I just might make it to programmer yet. (LMAO)