difference between allen bradlly and seimense PLCs

4,3,3 is wrong.

I thought the product was 36? I would guess A/B 9, Siemens 2, others 2.

You guessed correctly - the difference between Allen Bradley and Siemens is thus 7

L D[AR2 said:

You guessed correctly - the difference between Allen Bradley and Siemens is thus 7

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see I knew it was too easy.......but 4,3,3 fits.........

4 times 3 times 3 is 36

and 4 plus 3 plus 3 is 10....

if you gave the house number it would be different but with out it, .........there probably is another answer but how to know which answer is the correct one if more than one set of numbers fit?

unless I just missunderstood the question all together.

L D[AR2 said:

You guessed correctly - the difference between Allen Bradley and Siemens is thus 7

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so how does one know that 4,3,3 is not the correct set of numbers?

you have 2 solutions.

9,2,2 and 4,3,3 both work

what about

36,1,1 or 18,2,1 or 12,3,1 etc ?

L D[AR2 said:

what about

36,1,1 or 18,2,1 or 12,3,1 etc ?

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ok more than 2 solutions.............my question is to the maker of the puzzle how is one to know which is the corect answer?

I obviously missed a detail.

If I found one answer that works how to know it's not the answer? And if there are more than one solution, why continue?

The possibilites are as follows:
36,1,1 sum=38
18,2,1 sum=21
12,3,1 sum=16
9,4,1 sum=14
9,2,2 sum=13
6,6,1 sum=13
6,3,2 sum=11
4,3,3 sum=10

My house number is 13 as this is the only number that gives two possible solutions of which only one meets all criterea given.

dahnuguy said:

Peter...........


So then I started doing a save , block consistency check, then download ALL from the "Blocks" menu in the main window.

How is that simplier? Thats not online edit really.

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Block consistency checks are only done when you change a blocks interface. This is not a common thing to do, only in the early stages of developement.

The normal change is code within a block.

PeterW said:

Block consistency checks are only done when you change a blocks interface. This is not a common thing to do, only in the early stages of developement.

The normal change is code within a block.

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I am still in the development stage...........changing block interface and changing FCs inside FBs on occation.

dahnuguy said:

I am still in the development stage...........changing block interface and changing FCs inside FBs on occation.

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In early stages its not usually a problem though, as when a block is complex, you would attempt to develop that block and test that block in isolation. Changing the interface is not a large undertaking in that circumstance.

It's only when its a completed block integrated into a larger program that it becomes a hardship to change and that hardship may mean having to stop the PLC to re-create the DB.

I have seen very complex programs where numerous FB's were integrated within master FB's with shared DB's. A change to an interface would mean re-generating the code (as in this system the code was generated using a generator tool), you simply could not change one of the FB's without disrupting the entire the code.

This complexity was something they designed in and really does not need to be (in my opinion anyway) that complex.

Simple motor/conveyor control os so much better in modular form.

I have been told that AB can now do this and we do have rev.16 control logix but as we need extremely fast scan times and the projects are usually needed tomorrow, no-one has dared try this yet.


edit: by the way, changing an FC should never cause a problem as it does not have an IDB.

Like any system if you change a function block (parameters)you then have to find all instances of the block, change them.
however in siemens or in AB you will have to stop the plc for download as it will crash if still processing a call to the fb with wrong parameter assignment.
on line edits in siemens is easy providing you follow the rules & the ability to create a very large or many blocks & download then download the new calls in ob1 is a must on some plants.
By the way talking experience for me 26 years siemens, Ab, omron
20 years mitsubishi, koyo,imo and many other non descript plc's about 8 years
Even a few others most people would not come across like "Thorn"

Wow, I skipped a page in this thread and am not quite sure what direction it has "tangent-ed" off to. That being said, I found this thread just too relevant in my life to pass up.

Now, before I start I would like to say that in the US you will definately find that AB is the Windows of PLC's, and other brands being the Mac's with their hardcore following. Germany, just the opposite. I've spent alot of time in Germany while I was in the service. They have a blessing/curse of over-engineering. It's a blessing because no detail gets overlooked. It's a curse because every detail gets overworked.

I would choose AB. This is for the simple fact that while I speak passable German, English is my first language. Broken English being a second, due to all the Siemens manuals I've read. I would be much more willing to use a Siemens product had it been documented by someone who was extremely fluent in both languages. It just seems to me that they plunked their German manual into babelfish, and hit the Deutsch-Englisch button and what the fish crapped out is what you get.

Product quality for me is number one. Documentation is number two. And yes, getting support from AB is harder than getting one of those pig ears away from my dog. I found that with a little work I've found the answers to most of my questions by reading the manual. However, I found my customers are pretty wowed when I say something like "Free Parameterization" instead of "Parameter Entry".

So in short, and I know this probably isn't the answer you should hope for, go with whatever manufacturer has a strangle hold in your area. Getting support and manuals in a language that you speak will make your life easier.....

Psymon said:

It's a blessing because no detail gets overlooked. It's a curse because every detail gets overworked.

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Nicely put.

I would be much more willing to use a Siemens product had it been documented by someone who was extremely fluent in both languages.

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Or better, have someone from AB technical writers' group write a manual for them. Love or hate Allen-Bradley, one thing they do very well is the manuals.

Side note....

The Automation Direct (Koyo) manuals are the best for me, I bought the hard copies with the PLC and cards that I have used... I use them very often, the good part is I have found the answers the vast majority of the time and did not have to ask tooo many questions here