Two items today. On this April Fool’s day I hope you are enjoying a laugh – with the economic storm clouds gathering we do need to retain a sense of humour.
1. Major disasters in PLC projects (and how to avoid them)
In this complimentary 45 minute webinar, we will look at the intrigues of PLC installations, the programming of their hardware and software and how to achieve good practice. It is running on the 21st April. More details can be found at the end.
2. Drawing and thinking inside the engineering box
Most experienced engineers and technical professionals love sketching out solutions to problems – drawing little boxes when explaining or detailing some particularly ‘curly’ problem. I do feel, however, that drawing is underutilized as a tool when explaining concepts to fellow professionals and to laypeople – whether you are an electrician or advanced computer design engineer – sketching out the concept is an enormously powerful way to communicate. There is an overemphasis on the necessity of good written and verbal communication, and to our cost, we forget the incredible resource we have in drawing freehand to communicate really well. For those of you muttering that you can’t draw – probably the most difficult artistic requirement is the simple box. Admittedly, various exotically shaped boxes may be necessary, but you don’t need to be a Picasso trying out your cubist abilities. Learning mechanical and electrical drawing techniques was useful, but we must not downplay the incredibly powerful and achievable free-hand sketches we can create to explain a technical concept. I remember, as a young engineer, being fascinated by an experienced design engineer quickly and skillfully sketching on the back of his cigarette box. He communicated, succinctly, the modified wiring for a radar installation of a ship and then handed it to the marine electrician to continue with. It was idiot proof and powerful. We still have a ‘helluva’ way to go to easily draw on a computer though. It will be a good day when we can do this with the same ease and speed as on a piece of paper.
Donald Christiansen, of the IEEE, has written a fascinating and succinct summary of the progress made in engineering drawing over the past century (largely from the electrical and electronic point of view). In 1884, the technical journals at the time showed electromechanical telephones, telegraph keys, motors and dynamos all connected together diagrammatically – the only element shown symbolically was the battery. This is understandable as the battery would have been around a lot longer than telephones and motors. A few years later, the famous Nikola Tesla (the name of the new electric hybrid car), used circuit drawings that were a mix of sketches of generators and switches, but with symbols for coils, transformers and capacitors. The first part of the twentieth century saw the arrival of the wiring diagram – but still very pictorial in content. And then from the twenties onwards, electronics (esp. the vacuum tube) drove the development of schematics with symbols for some of the components; such as a vacuum tube’s grid (yes – I can still vaguely remember this), alternating between squiggles and dashed lines (the latter the eventual winner). And then “the box arrived”. The various functions of the radio receiver were called stages (e.g. the first one being the detector stage) and each was represented in a block format, as it represented an entire subsystem available “off the shelf”. Systems engineering has inspired a plethora of graphics tools ranging from flowcharts and Pert charts to matrices. Block diagrams play a key role here. The theory of system design uses a variety of exotic box diagrams and circles with arrows looping between them. Perhaps I am a little slow, but I am always dismayed by the complexity of these diagrams. The IEC has now abandoned the traditional logic gate symbols and also uses simple boxes for the ubiquitous ‘AND’ and ‘NAND’ gates. And the new resistor symbol is a long rectangle. Where has the zigzag shaped resistor gone to? As you would be well aware the integrated circuit (the ic) is also represented as a rectangle – even showing how the wires are connected together has now been abandoned due to the high pin count.
As Donald concludes somewhat wryly: “…. call it what you will – ¬block, square, rectangle – ¬the box is here to stay. Long live the box!”
The most extreme artistic expertise required of you, as an engineer and technician, is a box, so I urge you to redouble your efforts to communicate graphically wherever possible.
As engineering professionals, we must assist our children guard against what Karl Buhler believes: “…… As an essentially verbal education gains control, the child abandons his graphic efforts and relies almost entirely on words. Language has first spoilt drawing and then swallowed it up completely.”
In conclusion: Go forth and sketch!
3. Major disasters in PLC projects (and how to avoid them)
IDC Technologies proudly presents another live webinar in our popular series “Avoiding Engineering Failures”
When: Tuesday April 21
(Registrations close 24 hours before the first session). There’s a choice of 3 session times on the registration page at http://www.idc-online.com/IDCwebinar.html .
Where: At your desk!
What will it cover: This complimentary 45 minute webinar will touch on the many considerations of PLCs, including; installations, planning, purchasing, hardware and software reviews, testing, commissioning, and operational aspects. We’ll also look briefly at good practice for safety PLCs and the documentation requirements. It will not be brand specific.
This is a live, interactive webinar. And it’s free!
Join us from anywhere – and bring our PLC expert to your desk! If you are involved in PLC selection, programming and operation you will benefit from the session which will be live, in real time. All you need to participate is a computer with adequate internet connection, speakers and (ideally) a microphone.
Yours in engineering learning