The PLCopen organization and Automation.com conducted a joint survey of PLC programming preferences. The majority of over 200 responses from PLC users were from North America and Europe. Here are some of the results to inform you of current trends in PLC programming and users thoughts on vendors.
Survey Results
In the other category C and C++ programming was a prominent method. Many IEC 61131-3 programming environments provide the ability to create function blocks written in C and C++.
Process Control
One of the growing trends in PLC usage is a range of process control applications and this is reflected in the responses. Over 75% of respondents use PLCs in process control applications.
Programming Proficiency
Supplier Software
Respondents were asked how they believe suppliers are meeting their needs in different areas. Respondents provided a number of thoughts and comments.
Any comments or thoughts on how PLC suppliers might better meet your programming software needs?
Portability
- Multi-vendor portability with PLCopen XML might not be available or does not work always properly.
- Cross platform compatibility
- PLC suppliers/developers all hate their competitors.
- Greater cross portability of already developed code.
It is good that vendors are nowadays providing open scripting interfaces for the programming environments.
With those environments, code conversions and automatic operations are easy to made.
The idea that I can plug an ethernet cable from a ControlLogix PLC to a S7-400 and have them communicate directly is a fantasy.
OPC UA
- Adopt full OPC UA support!
- The user should be able to define its own information model and adopt to other standard models (i.e. packML and many others).
- PLCopen model should fully take advantage of the OOP capability in structured text.
The possibilities are fantastic, but the implementation is still lacking.
So that communicating on OPC UA should simply give you an interface that you can point on an instance in the OPC UA network and treat as if it was an object (FB) inside your program.
We have finally an object oriented communication architecture and object oriented programming!
But we still need to use a state machine to do method calls.
Why??"
Reliability
- IDE's not crashing or blue screening the OS
- Reliability issues occur with modern integrated programming environments.
Every vendor is too busy integrating their programming environments into one tool and implementing new fancy features while reliability and usability issues cause costly time loss for end users.
Programming Features
- Auto complete tag names while typing in ST
- Meaningful error messages
- Documentation that is easily accessible and searchable
- Software developers responsive to customers and their own support technicians.
- Allow for complex programming to be embedded within a ladder programming framework.
- Improve ladder instructions, to remove the need for complex training.
- Automatic code generation from SFC charts.
- Open system like C/java
- Compilation of text files is the way of C-type programing tools.
- Standard templates for PLC logic and standard boiler plates for HMI.
- Adopt modern programming techniques.
There are simple possibilities of versioning, archiving, managing, using libraries and conversion to another compiler / version / language.
The suppliers should have better knowledge and integration of source code control (Git), unit testing etc.
Note: Git is a distributed version-control system for tracking changes in source code during software development.
It is designed for coordinating work among programmers, but it can be used to track changes in any set of files.
PLCopen & OPC UA Collaboration
Industry 4.0 & Digitalization is driving towards modern IoT methods and court of this is semantic information models. The industrial automation industry has been behind in creating open semantic models and this is why PLCopen and the OPC Foundation created a joint working group to address these needs. Results include a standard OPC UA Information Model for IEC 61131-3 and PLCopen OPC UA Information Model for IEC 61131-3
OPC UA PLCopen Collaboration Overview Video
About PLCopen
PLCopen is an independent worldwide organization providing efficiency in industrial automation based on the needs of users. It was founded in 1992 and has its headquarters in The Netherlands with supporting offices in the USA, Japan, China, and Korea.
PLCopen and its members have concentrated on technical specifications around the IEC 61131-3 standard in order to reduce costs in industrial engineering. This resulted for example in standardized libraries for different application fields, harmonized language conformity levels, engineering interfaces for exchange, and transparent communication. Experts of the PLCopen members are organized in various technical committees and together with end users define such open standards.
PLCopen is a vendor and product independent worldwide association for topics related to industrial control programming. PLCopen consistently improves efficiency.
Because of the fruitful cooperation with our members, anyone can benefit from knowledge, support and create solutions in all fields of automation.
