In my dealings with users of EPLAN Electric P8, whether they are new users or experienced ones, there is a topic that keeps coming back quite a bit.
If your employer decided that you had go to back to using a drawing board to produce your electrical documentation, chances are you’d think it’s April 1st. Everybody working in a production environment nowadays is expected to use a CAD software of some sort to create production documents. The « CAD software » versus « drawing board » discussion is one that nobody would even dream of re-opening.
But still, even though we use CAD software tools for electrical engineering, our minds are still trapped within a 2D world, the pages on which we create our schematics. For our mechanical design colleagues, the shift has been slowly introduced some forty years ago, with wider adoption since the mid 90’s. The switch from 2D to 3D allowed mechanical engineers to think about what was being designed in practically the same way as it would eventually be fabricated. A threaded hole here, a bend there, a weldment between those two parts and so on. With this new paradigm, we started thinking in terms of model rather than in terms of printed page, which are now merely views into the model. A by-product of the modelling activities. Nobody wants to go back to having to capture the whole model in their mind, and then try to manually maintain a set of 2D drawings in sync with it.
With modelling, mechanical engineering activities were done faster, with much less errors, and as those systems evolved, reusing parts was now a reality. Today, by connecting those 3D models with ERP/PDM systems, we have dramatically improved delivery times, increased our product quality through reuse and have been able to promote the use of international standards.
Unfortunately, things have not evolved so quickly in the electrical engineering community, and being a very strong and vocal advocate of the modelling paradigm, I can’t help but get into those discussions.
My premise is that the very nature of electrical schematics is precisely what’s preventing us from viewing the problem from a different angle. Electrical schematics are based on a « language » made up of 2D symbols, and their interconnections, and so we have what is perceived as a « natural » match between the printed pages, and the conceptual representation of the controls schematics of a piece of machinery.
In the near future, we are bound to come across new ideas that will introduce the same revolution that we’ve seen in the mechanical world in the past decades. For now, we can still benefit from looking at our schematics as a model rather than the final result of our electrical engineering activities.
How? Here are some practical ways that can be implemented today, and for those lucky enough to have a software such as EPLAN Electric P8, they can leverage functionalities built from the ground up to support them.
1. View the equipment as a group of functions that work together to accomplish a goal. This is what’s known as functional design.
2. Think about the devices, or products, that are needed to implement those functions. This means thinking about the characteristics of those products, and how they physically connect together.
3. Think about the physical layout of the functions, how they will be located with regards to one another, and « slice » up this physical space in what we will call mounting locations.
4. Finally, think about all the further descriptive properties that can be assigned to those products. For example, a motor used to drive a water pump can have a function text that reflects its use in the context of that specific machine, thus helping production, installation and maintenance teams gain a better understanding of our machine as opposed to trying to infuse our equipment tags with magical numbers.
Those aspects of our equipments are precisely what the IEC/ISO 81346-1 international standard is built around. The function aspect, the location aspect and the product aspect work together to introduce a « 3D » view that will allow us to create projections, or views, based on the users, or customers, of our documentation.
For example, by introducing the location aspect, it becomes much easier for our warehouse colleagues to create bins of components divided by control cabinets. By using the function aspect, it becomes much easier to assemble our schematics from blocks that have been created, revised and honed over time, so much that we know them to be error free. Finally the product aspect allows us to define the individual vendor parts in such a way that we can perform validations about the number of wires allowed on a connection point and so on.
The EPLAN platform, of which Electric P8 is the flagship, is built from the ground up to support those aspects. Reports generated from the project have a very high added value that production teams will rely upon.
From a practical point of view, a point-to-point wire list sorted by gauge, colour and wire number, is of much more value than the electrical schematics for fabrication purposes. First, being based on the schematic, if this one is error-free, then the list will also be error-free. Then, having a list that gives a worker the wire gauge, the length, the colour, the markings, the source and target connection points, a termination method and even the routing within the cabinet, allows companies to recruit workers with a reduced set of skills with regards to being able to decipher electrical schematics. This reduces the possibility of errors introduced by personal interpretations of schematics.
Another type of data export, made possible by the product aspect, is transfer of the BOM to an ERP or PDM system. Those systems having revision management, make it very easy to compare the BOM between versions. It helps us avoid ordering too many of a very high cost item for example.
As things are today, a very popular CAD software, still heavily used in the industry, has ingrained the concept that the only way to view a machine is through the printed pages, when in fact, everything should revolve around the model, just like it does in the 3D world. The fact that we’re still using 2D schematics as the modelling tool is simply that we still haven’t found the new « language » that will provide a better mapping between the electrical reality, and the model.
A side-effect of this mentality is that draft people have turned their schematics into works of art, putting a lot of efforts in the way things look, but overlooking the most important part of our model, that is the data.
If we want to bring our companies to a greater level of competitiveness on the global market, we have to concentrate our efforts on what will bring the most value, and that’s not the looks of our drawings, but rather the properties, the data that underlies our designs.