Beckhoff vs. Allen Bradley... who is better?

lunenburger

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I have been working with Allen Bradley PLC's for almost 15 years.....

There are some rumors here that we are going to start getting in some equipment with Beckhoff PLC's in them.
According to the manufacturer, the packing machines run faster with Beckhoff than they do with Allen Bradley PLC's.

We use Controllogix PLC's in the packing machines we have on site now, so I am surprised Beckhoff would be faster...

Is there any advice anyone can give me about Beckhoff PLC's??
(programming info, tech support, quirks???)
 
Just a thought: packing (or any) machine should not run faster or slower because of what PLC you choose, unless you're using a different kind of communication etc. If scan time is a problem, tasks need to be spread out amongst consecutive scans, or code re-written in a more efficient fashion.
 
Not knowing much specifically about Beckhoff but knowing plenty about marketing puffery made by the less popular PLC manufacturers I would take any claim about the speed of scan time of a PLC significantly speeding up a process with a grain of salt (unless it was something monstrously high speed)

The true differences in PLCs (IMHO) are in the logistical details - ease of programming, ease of commissioning, service/field modification, parts availability, communications to field devices and SCADA/HMI, easy integrations with equipment are things that the big players (AB, Siemens, GE in that order IMHO) excel at and they charge big bucks for it. Beckhoff/B&R/Wago may offer more "advanced" products that offer faster scan times and 9 different programming languages but can I waltz down to a electrical supply house practically anywhere in the world and get a new power supply for one that's failed that very day? How easy is it to find a service technician to hire in the US that can at least futz around with RSLogix 500/5000 enough to get online and troubleshoot a bad sensor? How about one that knows how to do the same with Beckhoff? These figure into my considerations heavily.
 
Not knowing much specifically about Beckhoff but knowing plenty about marketing puffery made by the less popular PLC manufacturers I would take any claim about the speed of scan time of a PLC significantly speeding up a process with a grain of salt (unless it was something monstrously high speed)

The true differences in PLCs (IMHO) are in the logistical details - ease of programming, ease of commissioning, service/field modification, parts availability, communications to field devices and SCADA/HMI, easy integrations with equipment are things that the big players (AB, Siemens, GE in that order IMHO) excel at and they charge big bucks for it. Beckhoff/B&R/Wago may offer more "advanced" products that offer faster scan times and 9 different programming languages but can I waltz down to a electrical supply house practically anywhere in the world and get a new power supply for one that's failed that very day? How easy is it to find a service technician to hire in the US that can at least futz around with RSLogix 500/5000 enough to get online and troubleshoot a bad sensor? How about one that knows how to do the same with Beckhoff? These figure into my considerations heavily.
Yep, and don't forget to take Real MTBF into consideration.
 
Is there any advice anyone can give me about Beckhoff PLC's??
(programming info, tech support, quirks???)

Yes, it is quite a different beast. It is a powerful, flexible and very capable competitor to Allen Bradley or any other major PLC brand, but you would have to go through a steep learning curve with it. You will be well-advised to convince your management to arrange for training.

The online help is, IMHO, deficient but the tech support for us has been very good. It might be a good idea to establish contact with your area Beckhoff sales/tech support office, especially during the initial time.

A lot of people actually get to love Beckhoff... over time :)
 
According to the manufacturer, the packing machines run faster with Beckhoff than they do with Allen Bradley PLC's.

Sounds like BS to me. More like "Well, Bechoff hardware is cheaper, but we'll still sell the machine at the same price and keep the difference as profit."
 
Here is a good tutorial on Twincat 3 (Beckhoff's newest programming software) if you want to get your feet wet:
http://www.contactandcoil.com/twincat-3-tutorial/

The same author wrote a review of the software and makes some comparisons to RSLogix 5000 that you may find interesting:
http://www.contactandcoil.com/automation/industrial-automation/the-twincat-3-review/

(I should point out that this review is almost four years old and most of the problems he mentions have been fixed. I've been using Twincat 3.1 for at least a year--on Beckhoff hardware--and have never experienced a crash.)

We've started using Beckhoff CX's on some of our larger machine projects. I attended the advanced programming class in Minneapolis which was a worthwhile experience. I'm the kind of guy that likes to teach myself whenever possible, rather than going to a class, but I have to admit that it's difficult with Beckhoff. They have a comprehensive online documentation system, but it doesn't provide much in the way of training materials, and many things in Twincat can be unintuitive. The good news is that Beckhoff's US support is well-staffed, responsive, and free.

Things I like about Beckhoff so far:
* EtherCAT. It really is a "beast" as Whitlock mentions in his review. Remote I/O is amazingly simple to implement and the speed is phenomenal.
* Development software is free. Additionally, you can use any of their add-on functions with a 7-day trial period that can be re-upped as many times as you want. You don't pay for a runtime license until you're certain it's what you need.
* Great support via email or phone.
* Cost is waaaaay less compared to AB.

Things I don't like:
* Steep learning curve in Twincat. However, I've been drinking the Rockwell kool aid for 15 years and am certainly biased. Someone with other experiences might have a different opinion.
* Some things in Twincat are not near as polished as RSLogix. The ladder logic editor takes a bit of getting used to. The Visual Studio interface seems a bit overblown to me.
* Limited support in online forums, especially compared to AB.
* Limited availability. Beckhoff sells direct, not through distributors, so you have only one source for parts. That said, I've never had any issues getting parts in a reasonable timeframe. Anything that isn't stock in the US will be 2-3 weeks from Germany.
 
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We use AB stuff for our general purpose systems, but we use PacDrive systems for our packaging lines due to the number of axis.

So sometimes there are reasons to use one brand over another.
 
I think "x runs faster than y" is usually, "we found a way to use x that runs faster than the way we used y." Good on them, that's innovation, that's capitalism! Although, if they are using Ethernet I/O (EtherCAT), I suspect it runs much faster than AB can (Ethernet/IP).
 
Thank you for all the advice.....
The thing is... I am in a 30 year old plant that has been Allen Bradley from the start. We have close to a hundred plc's here and hundreds of spare parts.
(many obsolete now...)
But when the packaging company says Beckhoff is faster and cheaper, the bean counters eyes are going to glaze over. (more dollars per minute production)

"A PLC is a PLC right???" says the bean counter....
 
Yes.. from the bit of reading on Beckhoff I've done I believe the difference in speed is coming from the communications.
There are multiple servo axis on the packing machine.
And the claim that Beckhoff is faster is coming from the packing company who have been making Controllogix machines for years and not a sales rep from Beckhoff.....
 
After 15+ years working with Beckhoff and 20+ years with AB, and still working equally with both, I will attempt to give my unbiased experiences:

Cost of Hardware and Software
Beckhoff is far ahead on this. The Beckhoff TwinCAT software is free when used for programming. It only costs when you want a run-time.

As for hardware, when comparing the approximate equivalent of controllers, AB is about 3x the cost of Beckhoff.

Software Usability
TwinCAT has a bit more of a learning curve and the ladder editor when compared to RSLogix, is just horrible. But when comparing the other languages, such as SFC or ST, then AB is horrible in comparison. TwinCAT (technically CodeSys) has been designed very well for re-usability, while RSLogix does not do so well with it. For example, when you become efficient with TwinCAT, you will begin to build a library of functions and function blocks that are easily imported into new projects.

After many years of experience, I can develop a moderately complex program using TwinCAT in about half the time it takes to do the same program in RSLogix.

System Scalability
By this I mean by how easy it is to move up to higher end hardware. With AB let's say you have a current machine with an ML1400 and you maxed it out and need to move up to a ControlLogix. You will be pretty much re-writing the program.

In the Beckhoff world, let's say you started with a CX8090 (about equivalent to an ML1400) and needed more IO and a faster processor, so you move up to a CX5000 series. Your program is re-usable as is. TwinCAT programs are the same matter on their entry CX controllers or their highest end controller.


Tech Support from the Company
I have to say Beckhoff wins in this category mainly because they will provide support for free whether you purchase their product or not. AB always wants their hand in your pocket even if you bought their hardware.

Community Support and Knowledge Resources
AB wins this one hands down. It's easy to see when an AB question arises on this forum that many more people will respond versus when a Beckhoff question is posted. As already mentioned, you will most likely find someone in your area that has AB knowledge already, but slim chance for Beckhoff.

Beckhoff TwinCAT does have a little going for it in that the software is CodeSys based. This makes a difference because you don't need to find a specific Beckhoff TwinCAT programmer. If you find someone that has programmed any CodeSys based system, such as Wago, Turck, Bosch, etc, then that person is already experienced with programming TwinCAT. Although this expands the knowledge resources, it still falls quite a bit short from AB's extensive knowledge base.

Hardware Availability
I'm going to say AB has a slight edge on this because they have distributors every where while Beckhoff sells everything from Minneapolis. I'm only giving a slight edge because it seems that over half the time I go to my AB distributor, they do not stock the part and I have to wait days or weeks to get the item.

If Beckhoff would implement logistics as well as AutomationDirect in which you can go to the web site and order parts at any time and receive it in 1-2 days, then Beckhoff would step way ahead of AB in this category. But that is only my wishful thinking.

You can kind of get a gauge of Beckhoff hardware availability by searching Ebay. Maybe 10 years ago, Beckhoff hardware was rare on Ebay, but AB was abundant. Now Beckhoff hardware has a significant presence on Ebay.

Preferred Network Protocol
Beckhoff's preferred protocol is EtherCAT. EtherCAT is very efficient and fast, much faster than AB's Ethernet/IP.

AB's preferred protocol is Ethernet/IP. Under the hood it is a very complex and inefficient protocol. However there is much more hardware available that supports Ethernet/IP.

Beckhoff does a very good job of providing support for the widest range of protocols. I do believe they even now provide hardware (or its in the works( with Ethernet/IP scanners (master). This means with a Beckhoff system you can use both Ethernet/IP hardware and EtherCAT hardware.

Reliability
I'm going to say AB and Beckhoff are equal in this area. When I first started using Beckhoff, it was very rare to have a failed piece of hardware. It seems within the last 5 years, I have started seeing a measurable amount of bad hardware. Not sure why, maybe they moved their manufacturing to a place that is not as quality conscious. My very first system I installed in the year 2000 ran without a single hardware failure up until it was decommissioned this year.


The comment about Beckhoff making a machine faster, I'm going to call a bunch of sales BS on that. It will definitely make your IO updates faster and TwinCAT can scan much faster, but it will not make your machine faster.

The only way I can see this happening is on a very high speed machine. Let's say you have a ControlLogix that is scanning the program at 10ms. That means the fastest that machine can react to something is 10ms. If your machine speed was limited by this reaction time, then Beckhoff could improve it. TwinCAT is a compiled language that executes much faster. That same program in AB that scans at 10ms can potentially scan with TwinCAT in 0.1ms. With EtherCAT you can refresh your IO at that same 0.1ms also.
 
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But when the packaging company says Beckhoff is faster and cheaper, the bean counters eyes are going to glaze over. (more dollars per minute production)

"A PLC is a PLC right???" says the bean counter....

Yes, and downtime is downtime.

As others have said above, you could make good arguments for either AB or Beckhoff - but it takes more than a PLC to make widgets.

Have you factored in the cost of getting software and licenses for all the equivalent Beckhoff products? Are any of those software packages going to require updated PC's, newer versions of Windows, virtual machines, new technician laptops, etc? Have you factored in the time it will take to install, configure and test that software?

Have you factored in the cost of getting everyone suitably trained and up to speed on a totally different, totally new platform? Not just the plant engineer, but everyone who ever looks at the stuff? Maintenance, night shift, projects team, etc?

Have you factored in the cost of obtaining, cataloging and storing all the spares required for another line of PLC's?

You buy a PLC once, so it's an upfront saving. But there are also a lot of upfront costs, and if you don't do it right, there are a lot of ongoing costs that will wipe out your upfront penny-pinching in a heartbeat. How much does it cost to have the line down for even an extra hour because you couldn't find the laptop that has the Beckhoff software on it, or because you don't have that particular software package installed and licensed yet, or because the night shift guy didn't get trained yet and has to google how to get online with the PLC, or because that particular spare part is not in your stores, or is buried somewhere in a box in your storeman's office because nobody has given him a budget to buy more shelves to store all of this new hardware?

Even once you are all trained, until everyone has enough hands on experience to be as fast or faster than they are/were on the AB gear, every instance of downtime represents a net loss over AB, because it'll take you longer to diagnose the problem.


This is not to say "don't do it". Beckhoff is a valid choice, but if your bean counter's eyes are glazing over while their imaginary pile of beans gets bigger and bigger, you need to slap them across the face with a Beckhoff catalogue and make sure that they've factored all of the above into the bean pile. Do it PROPERLY, or don't do it at all.
 

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