COURSE 520 and 530

Technical Training provide two separate courses on PLCs. This is because we believe that the majority of people only want to fault find on PLC systems and a small number of people want to learn about programming them. We therefore created the two courses with this in mind. Course No 520 is the PLC fault finding course and course 530 is the PLC programming course. Some candidates might like to attend both courses, and of course this is perfectly OK but they should really do the PLC fault finding course first.

Part of the reason for making the two courses separate is that there is an overarching health and safety issue at stake: should the candidates be modifying the programs inside the PLCs? Many basic PLC courses begin by showing the candidates how to write a simple program and this may very well be a valuable learning experience but we think that it also runs the risk of teaching the candidates bad practices - would they be authorised to write or modify PLC programs back at work? For this reason we have taken any type of programming or program modification out of the PLC fault finding course and that of course means that this course is free to concentrate on fault finding - making the course far more relevant. Some companies don't have clear policies on this but we think that it's important that our candidates are clear about what they should and shouldn't be doing when they return to work. The HSE historically produced some interesting books discussing these issues but to date there are no regulations or guidance notes that specifically control or guide managers and engineers through deciding on the authorisation levels between those that are allowed to modify a PLC program, those that are allowed to read it only and those that mustn't touch the PLCs at all. A proper procedure should also be in place for how program changes should be controlled and again the HSE don't give any clear guidance on this, even though there are several accidents annually in the UK that have been blamed on poor control of PLC systems.

On both courses we use a multi-platform approach: the courses are run with 4 different PLCs at the same time and the candidates can migrate towards the ones they are interested in the most. We think that this a more honest way of teaching the courses, as making the course manufacturer-specific and expecting the candidates to attend several different variants of the same course would mean that they experience a lot of overlap between the courses (and waste a lot of money!) We use Allen Bradly, Siemens, Omron and Mitsubishi PLCs. We also think that this approach leads to a much more holistic understanding of PLCs, allowing the candidates to subsequently deal with any make or model of PLC. See the course description for more details.

Interestingly, the approach we are using on the fault finding course means that the candidates could (at least to some extent) apply their understanding to various other control systems too (because we're only treating the PLC as a box that has input and output lines and a program inside it) so their knowledge would be just as applicable to Programmable Relays, Remote I/O systems, SCADA etc.

The PLC programming course does of course involve programming. The candidates are shown best practices like structuring their programs, labelling the symbols and commenting on the rungs. We then set several exercises where they have to write their own programs, gradually building up the complexity as we go along. Eventually they are expected to produce a fully working program that controls our conveyor systems properly. See the course description for more details.

Please click on the following links to visit the two PLC courses:

Course 520: PLC Fault Finding

Course 530: PLC Programming