Automation Direct's Productivity 3000

[Wagnerjp]

This is a general question. We have a new controls project here with lots (40 +) temperature control loops, plus a handfull of interlocks. I am considering using a Productivity 3000 for this project -- it looks very intuitive to program, especially after my last project using Beckhoff. Has anyone had any experience with this PLC?

Another project we are considering using the above PLC for is control of a Cavro sampling robot which involves sending ASCII commands via 232. Part if the complication is the need to generate CRC codes, wait for acknowledgement strings back from the robot, etc. The 3000 model has a serial card available. In general, how straightforward is it to program to send serial strings, generate and check CRC codes, etc. with this PLC?

I would appreciate any feedback on this. Thanks.

 

[Archie]

I am considering using a Productivity 3000 for this project -- it looks very intuitive to program, especially after my last project using Beckhoff.

There is no denying that Beckhoff/Codesys has a bit of a learning curve, but once you fully understand how to utilize features such as custom Function Blocks, development time is tremendously less. I find that it will take 2-3 times as long to program the same thing on systems that does not have all the tools that TwinCAT/CodeSys does. It's like someone taking everything but a hammer and screw driver from your toolbox then saying "build a house". It can be done, but having the right tools makes all the difference.

 

[Wagnerjp]

Productivity 3000

Thanks for your reply. Here's the thing -- my company is a startup chemical R&D and our projects are one off -- no economy of scale. I developed a custom FB for our Beckhoff system-- the simplist possible -- for scaling integer analog values to real. I couldn't believe that Beckhoff didn't have a ready made FB for such a simple and common function. The math is very easy -- but developing and deploying it took some time and a few calls to tech. support. I have taken a look at Beckhoff's custom temperature control FB and it is not user friendly at all -- I think that for common control strategies like scaling or PID control a ready made, graphical, fill-in-the-blanks block with direct linking to tags is a lot easier to use than having to declare a whole pile of variables, (once for the FB and then again for the actual variables used). Beckhoff also charges extra for their control toolbox which I think is ridiculous -- should be included I feel. But it probably is as much a matter of taste and background as anything else. Some control engineers arrive at real time control via a programming background -- and others started with control before digital and then learned programming when digital control took over. Maybe you can tell I am from the latter group!

Thanks again for your input.

John

 

[Archie]

There are actually a lot of function blocks that already exist, but the problem is usually finding them in all of the libraries. If they don't exist, there is a very extensive open source library www.oscat.de . I don't disagree at all that it is absurd that you have to pay for additional libraries. However I also think it is absurd to pay for programming software when it can only be used on the same manufacturer's hardware that a premium price is paid for. TwinCAT software for programming their PLCs has always been free.

The real power of custom function blocks is re-usability and also the ability to make your program more intuitive. For example, before learning TwinCAT, I was an AB programmer. So I got used to the Scale With Parameters instruction. In TwinCAT, it took me about about 15 minutes to make that function block and now I have reused it hundreds of times over the years. I just recently had a case where a custom function block made my program much more intuitive and maintainable. A while back I had written a chunk of ladder code that would calculate the cans per minute rate coming out of a machine based on a gear tooth pulse. I went back to reuse that code on a similar machine, but had a different tooth to can ratio. I had trouble figuring out my own program. So I made a function block that took the pulse input, the gear teeth per revolution, and the cans per revolution. Now looking at the new program, it only takes seconds to understand what it does and if it's reused, it is very easy to know which numbers to change.

Of course FBs are only one of the tools that makes TwinCAT more productive. Utilizing any of the language options can be a huge time saver. Have you ever had to do complex math in ladder, then try to figure it out years later? If you ever learn to use SFC for state machines, you will hate ever having to do state machines again without them. There are a multitude of useful tools that many PLCs lack.

I'm not saying that TwinCAT is the end all solution for everything because I do programming on a wide range of hardware and software. I'm just saying that it's hard to fully appreciate everything TwinCAT is capable of until you really get to spend some time with it to discover the tools and what they do best.

 

[rguimond]

This is a general question. We have a new controls project here with lots (40 +) temperature control loops, plus a handfull of interlocks. I am considering using a Productivity 3000 for this project -- it looks very intuitive to program, especially after my last project using Beckhoff. Has anyone had any experience with this PLC?

Another project we are considering using the above PLC for is control of a Cavro sampling robot which involves sending ASCII commands via 232. Part if the complication is the need to generate CRC codes, wait for acknowledgement strings back from the robot, etc. The 3000 model has a serial card available. In general, how straightforward is it to program to send serial strings, generate and check CRC codes, etc. with this PLC?

I would appreciate any feedback on this. Thanks.

I've used a Productivity 3000 to replace a Delta building automation DCS. I was very impressed with interface - very intuitive. Lots of nice features, like debounce coils. For anyone used to RSLogix 500, you'll really appreciate these! If the plant wasn't full of SLC, ControlLogix & MircoLogix, I wouldn't hesitate to use this PLC line for all replacements and upgrades. I wouldnt hesitate using them exclusively in a new plant, either.

 

[FactoryTalktotheHand]

They just came out with Productivity 2000. I like how the analog modules have a built-in OLED display so you can see what each channel is putting out or getting in as opposed to an "OK" light