Operators pushing the wrong button...How to prevent.

[robh 12]

Sigh... How do you make an operator push the correct button, and not the wrong one? We have two tanks used for a batch process. Because I am not allowed to post the specifics of our process on the world wide web, lets call them Tank A and Tank B. There are three items that need to be put into each tank, lets call them 1, 2, and 3. The operator transfers 1, 2, or 3 to A or B by using a touch screen button that they have to hold for 3 seconds. Each tank has its own screen that has buttons to start 1, 2, or 3. These screens look similar other than the extremely different color and giant text at the top of each screen letting you know what tank you have selected. Last night the operator had the screen up for Tank A and started adding 2, problem was it should have gone to Tank B. So I have been tasked with making it so the operator can not do this again. Suggestions that have been thrown at me are things like "add an are you sure you want to do what your about to do button", problem I have with that is I have noticed from experience is that operators tend to become complacent with just hitting buttons, if operator can't pay attention to what they are doing why would they pay attention to an "aysywtdwyatd" button. Another suggestion was to have the HMI switch screens after the item has been transferred. Near the end of the day and I feel like I am tearing my hair out. Suggestions on how to make an under trained operator with no accountability not push the wrong thing?

[Crossbow 296]

It's really up to your application how you limit this. I mean are the buttons for 1 and 2 and 3 all the same address? Or do they use different addresses for different tanks? I would set it up so that the buttons to A are tied to a specific screen number being displayed. I mean how do they know which tank it is supposed to go to? Without that, it would be impossible for us to make recommendations.

[Crossbow 296]

Or there's always the hire more qualified operators option.

[TimWilborne 108]

How far away are the tanks from each other and how far is the screen from tanks? Could they be split into two screens or buttons at the tanks? I think we should drown some worms and think about it a while :)

[michael G 2]

Can you have a sequencer running the tanks loading sequence and disable the button not inuse? EG include the operator actions in a sequence for each tank I.E. Tank A needs product 1 so only product 1 PB is available Tank B needs product 2 so only the product 2 PB is available +1 the Are you sure button is useless

[cHud 25]

Can the operator put item 1,2 or 3 at any time into any tank? Or must he put item 1 then 2 then 3 in tank A, and item 1 then 2 then 3 in tank B? As Micheal suggested if its a sequence you can disable and enable buttons according to which step they are in at that moment

[BobB 58]

Cut the fingers off that push the wrong buttons!! Old saying you can make things idiot proof but not operator proof!!

[chelton 66]

Maybe you can change the buttons so they are not maintained. Then while the operator is holding the button you can have a display that tell them they are adding part 1 2 or 3 to tank "A" or "B". Surely they'd have time to read the HMI whiltst standing there with a finger on the fill button.

[TimWilborne 108]

One other thought, do they have paperwork they carry along when filling the batch? Could a bar code be added to it that includes tank assignment or does the operator determine which tank to start the batch in?

[robh 12]

Yes! They record the information that is displayed on the screen, batch number, time, and amount used. Capitan Awesome would have seen his mistake had he filled out his paper work and followed the procedure.

[PdL 71]

Let them have push 2 buttons simultaneously for 3 seconds. Three buttons for the additives, and a final button that says TANK A on the screen for A and TANK B on the screen for B. Pretty useless but perhaps the slight increasing brain activity that is used to push two buttons at the same time will get that 1 second of attention the operator needs? Oh, and when they do it correct, open a hatch and give them some peanuts. I think this is how they do it with chimps.

[TimWilborne 108]

[robh 12]

I could also add a safety mat that requires them to stand on one foot! Peanuts? Think of the safety issues that would develop, choking hazard, peanut allergies. Salted or un salted? "Peanuts are dispensed to fast", "It gives me 3 but I only want two, why are we wasting the third one", "where do we put the shells"...

[Shiner 2]

Try candy corns....noone is allergic to sugar. What about eliminating the screen label for tanks ect.....once an operator pushes a button for fill with material 2, have a popup "which tank do you want this material to go to" and have them manually enter a number from a popup keypad. Then there will be no button confusion or I didn't see what screen I was on garbage. It will be, you manually entered the wrong number?!?! I guess this does not help for those operators who didn't like Count from sesame street.....one tank ah ah ah.

[TConnolly 13]

Eliminate the operator ingredient buttons altogether. The operator selects a recipe. Presses start. Everything else is sequenced by the controller.

[BobLfoot 302]

+1 to the above idea. If all speeds and feeds are known with a sequence then amount which can be made is predictable. This should give you more output not less. Just be sure to sell it to the operators that they get more loafing/break time with a sequencer but hush hush don't tell the boses they think it makes em work harder.

[robh 12]

That would be the ideal solution, and it is what we are working on getting to in the "future". Right now the entire system does not have the required components to make it fully automatic, and there are a lot of expensive components needed.

[TConnolly 13]

You have HMI screens. So you have the required components. All you need is the software. I'm perplexed, what other components to you need? Is the operator also heaving buckets of stuff into the mix by hand? Even if that is the case, can't you still automate the amount of stuff he is putting in by pressing buttons and have the HMI tell him when its time to scoop stuff in by hand and how much?

[robh 12]

The three ingredients are are automated. They are added by metering pumps to ensure that the correct amount is added. Getting them to select the right one under the right circumstances is difficult. The problem right now is that "production" can not decide on a consistent way of making their batches the same every time, maybe its because I am not a super genius, but I haven't found a way to make a MicroLogix 1400 see into the future to prepare for whatever they think they want to do that day and I do not have an importance level high enough to make them do it one way or the other.

[BobLfoot 302]

OK let me break this out for my understanding. A. You are making a batch of Widget Goop and into this batch you might add any or all of three metered ingredients. B. If a is true then you have the following possible recipes. 1) Only ingredient 1. 2) Only ingredient 2. 3) Only ingredient 3. 4) Ingredients 1 and 2 5) Ingredients 2 and 3 6) Ingredients 3 and 1 7) All three Ingredients added. C. This means you have 7 possible recipes. You could use 8 integers to track this process. Integers 1 thru 7 would represent recipes 1 thru 7 and bits 1,2 & 3 would be on/off if that ingredient is enabled for that recipe. Integer 8 would be the current recipe and a 1 would mean that ingredient could still be added a zero would mean it was already added. You would start a batch by copying the master (1-7) to the working (8). When a product was added you would zero it's palce holder and that could then grey-out / deactivete that button. Hope this makes some sense.

[TConnolly 13]

Another way could be like this. File N100, 101, and 103 are integer files containing ten elements to define a recipe that can have a variable number of ingredients up to ten steps. File N100 contains the ingredient numbers, File N101 contains the ingredient quantity. File N103 contains the blend time. Word 0 is the first ingredient and quantity, Word 2 is the second ingredient and quantity, etc. So, Word N100 N101 N103 0 5 2 0 1 1 4 0 2 3 7 60 4 2 1 60 5 0 0 <- end of this recipe 6 0 0 7 0 0 8 0 0 9 0 0 You can use a counter to step through the recipe and indirect addressing to determine which ingredient to to use. The ingredient numbers control various feeders or prompt the operator to add an ingredient manually. Edited 23 Sep 2011 by Alaric

[robh 12]

Batch of Widget Goop. In a perfect world operator would make goop by adding ingredients A, then B, Then C. Problem is that it takes 20 minutes to make and add A (A is mixed with water in a tank then added to the batch). So operators turn the sequence into A, B, A, C, B, A, C, B, A, C to stay ahead of the game. I have no problem with this as it works fine either way they do it, IF they would do it the same every time. Hard to make things sequential if they want to change the sequence everyday. Sorry for the delay in responding but we have just started running production here 7 days a week instead of 4. Good problem to have.

[BobLfoot 302]

Maybe I missed something but if a batch of Wdget Goop needs 1 quantity of A, 1 quantity of B and 1 quantity of C in each batch the string sequence you list has 4 parts A , 3 parts B and 3 parts C so at best it made three good batches and the start of a fourth or a mess of goo. sounds like programming a sequential system and forcing operators to observe is the wat to repeatability. But that will be a CULTRUE CHANGE, to be sure and an uphill battle.

[robh 12]

Thats exactly what it is. Last night I revived a call saying the pump for "B" stayed on way to long and emptied the sight class. Something must be wrong with your program. After more shenanigans on the phone it was determined that "not me", "adjusted" the metering pump from 15% to 75%. When I came in this morning I asked who got fired. Unfortunately everybody still works here. But we solved that problem...we build new guards over the dials.

[Shiner 2]

Something must be wrong with your program. Don't you know, programs have a mind of their own, always changing by themselves to give production a heart attack. Those physical devices out in the real world exposed to the dangers of process, or even more scary, the meddling hands of the incompetent, can never be the problem. Had that same call today, got onsite, they asked "Where is your laptop?" I said, didn't this work when I left weeks ago? answer yes. Well then maybe a broken prox is the answer and you just paid me two hours minimum to find it!!! Thanks.