selling a locked user defined function block

ganutenator

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1) I am poor
2) I have written some useful plc code in the past
3) Anyone here ever try and sell a user defined FB?
 
1) I am poor
2) I have written some useful plc code in the past
3) Anyone here ever try and sell a user defined FB?
No, but we sell motion controllers with firmware that the customer cannot modify.
I don't see any problem with selling FBs that work. Be ready for tech support calls if they don't.

What kind of PLC code to you deem useful? There are a lot of topics that come up over and over again here. I can see why people would want to buy ready made code. Sometimes time is more important than a few bucks.

I will pay for VPN software. Viscosity is just a user friendly version of Open VPN but I still buy it because makes implementing a client VPN easy. I wish there is a Viscosity for the Raspberry PI. I would buy it. Right now I am using my Raspberry PI to write this.

Normally I use a I7-4770 Zotac box. Yes they are old. Yes I can afford anything. That isn't the point. Being able to make what you have work is gold.
 
Virtually all code I have written has been paid for by the customer, so never protect it, I have protected code for OEM's at their request & given them the passwords etc. (they paid for it, these were standard machines they sell).
TBH, why bother, PLC code is just applications of the PLC manufacturers functions, I have never passworded any of my code, I have often been involved in replacing systems that have been protected, even if you do get the code more often than not it is just as quick to re-write it from scratch rather than try & decipher someone elses code.
I can understand why some protect their code i.e. stop unscrupulous people cloning machines/plant that some company have spent a lot of time & money on.
As for producing functions & trying to sell them you would probably find not many people would buy, but good luck if you can make a bit of money out of it.
TBH, any decent PLC engineer could produce similar code. Like Peter has said, be prepared to support it.
On another note: (not knocking intelectual rights) A plant supplied by a company was designed to our specification, we paid for the development of the complete system hardware design & software, the supplier had slightly under estimated on the controls side & locked the applications, it was noted that this supplier was known for it, the control was to say the least very poor, they charged us considerable sums to get it right or if we needed any enhancements doing we were being held to ransom. In the end, I re-wrote the code for the 8 PLC's, we had another systems house to do the Scada & recipe control (I spent the whole time at the suppliers helping them with the code on the scada & getting it right). We estimated the cost of this to be less than the continuing costs of having the original supplier keep making changes & messing it up. In the end I believe that their attitude to ripping the customer off actually cost them future work worth a lot of money.
 
In my very early days of programming I was asked to retro fit the controls for a mattress making machine.
It was my first ever plc project and in retrospect I was way too green to take it on.
But there were 20 of the same machine and they wanted them all doing.
The machines were ancient and the control voltage was 36v ac?
Getting electrical spares at that voltage was becoming very difgicult.

I really struggled but eventually got it working with terrible code.
I was then given the other 19 to do.
I improved the code with every machine until it was probably perfect.

One day I caught a rival bedding company downloading my code from machine number 1. I thought 'good luck to you - even I don't understand what I have done.

I can imagine what they said when they thought they had stolen the jewel in the crown
 
When I started programming for the first machinery builder I worked for (using RSLogix 5 and 500) I saved excerpts in sample code programs so the next machine I could copy the rungs and paste them in my current project. I even created a base main project template with data files expanded, some standardized bits and integers labeled, and a few "setup" rungs.


Even with just me using my own code I ended up finally abandoning that idea as each similar task on every machine turned out to be different, and the editing of the code was probably the same as parky encountered for his quote above.
 
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Sure it is possible and that is what codesys store is about, selling libraries/code.
It can be done for any other platform.

Who would pay and how much requires good market research and I am sure the more you dig into it the more you will be able to narrow down what kind of FBs (services) developer are willing to pay for. Documentation and support is going to be essential part of the marketing.
Have a look at the compiled libraries you get with the different platforms to get an idea of what developers consider valuable.....communication, PID, Motion control..etc.
Twincat has a huge automation library that includes HVAC and I think batch processing blocks..
 
Can you guys see the difference between selling code that the customer paid for and code that you wrote on you one dime/time? I think it is fair to charge for code you write on your own dime/time.

"Even with just me using my own code I ended up finally abandoning that idea as each similar task on every machine turned out to be different"
Yes, it takes a lot of effort to write truly flexible code.

The saying we have around here is that the customers will only use about 1% of the code and everyone want their own special 1%. The trick is to be able to handle 99.9% of the applications with your code.

I am a big fan of re-usable code and having to re-invent the wheel.
 
It was years ago Peter posted that code should be 50/50. 50% making the machine run and the ither 50% diagnostic as to why it isnt running. I do a lot of machines that are sequence based. My sequencer code is solid. The diagnostic is where we do the most programming on.

I have made a good living re-writing code for 1 company. They hate having code locked by OEMs. If its a 1 off machine, than I think the customer owns the code. If its a cookie cutter machine than the OEM owns the code. If the paid for the time and development than its theirs.
I hate locked code only because when it comes to troubleshooting it makes it very difficult if not impossible. 1 OEM locked to code so of an IO card needed placement you had to call them and have a tech come out. That OEM lost a $600k order for a new machine because of that.
 
A number of vendors are now offering libraries or "apps" that are both developed by them and other users. The examples I can think of are the likes of Ignition and PLCNext.

If there's demand for what you develop then there is a market for it, and how you interact with that market is entirely up to you.
 
1) I am poor
2) I have written some useful plc code in the past
3) Anyone here ever try and sell a user defined FB?
So you are asking if it is possible to sell the code only, without there being a sale of a machine.
I haven't heard of anyone doing that, except for the process industry. For specific processes you can buy complete packages including the HMI part.

In principle it should be possible to sell code packages with useful functions.
Practically I think it will be difficult to reach the potential customers.
 
everyone here uses premade code to make their life easier.... just depends on how you look at it...

SCP (scale) instructions
BSL (Bit shift)

etc. we all use them, and somebody wrote the little bits that make them work. I just see the problem being, how would you sell them and to who? unless you're making very specific code, you would have to search out the most popular automation products that don't already have a good AOI or code from the manufacturer. and then make something people would want to use and then find out how to advertise to them.
 
I think he means to sell some specific code block for a particular problem or industry. Not a generic code like the ones you have as a library from the automation vendor.

I just want to mention that there is the OSCAT library which has many useful functions for IEC61131-3.
They are cross-platform with ready to use libraries for PCWorx, Codesys and Siemens S7.
It is open source though.
www.oscat.de
 
Yep. And I bet it’s for car wash control

Regardless, if you can sell it - go for it
 
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