In the railway and signalling standard from CENELEC, i.e. the EN 50126 or 50129, it is mentioned that one of the strategy (if I am not mistaken) for designing a safe system is through the use of Defence in Depth. My understanding of this is that the there are various ways a function can be…
Someone asked recently on Linkedin, why aren’t railways using GPS for their train positioning. Here’s my answer below: 1. GPS is limited by infrastructure and obstruction2. GPS has lower accuracy, say for example, a norming point/balise. Quick google and saw it says around 1 – 5 meter accuracy. Based on this two points, it’s not…
I have just finished IRSE module C and D today, a completion of the IRSE exams. Altogether there are 4 modules, A, B, C and D, and I started taking the exams with module A, in 2022. It has been 3 years constantly preparing for exams, that today I feel a bit ’empty’ after completing…
In railway signalling, one of the most problematic or challenging part is, subjectively, the level crossings. It is the part where the road meets the rail, where normal railway operation which is rigid and structured, meets the road operation that in some ways, very loose and has many variables. It’s an interface and interface always…
I had the fortunate opportunity of joining a ‘hands-on’ study session last weekend. It was organised by IRSE Younger Members, and graciously hosted by Signet Solutions in Derby. Was it useful? Yes. What did I learn? Other than how to use the word boffins (clue: it is the antonym to buffoons and normally accorded to…
In systems Engineering thinking, and more specifically in railway signalling I guess, the term system definition means defining what your product (or system) is going to do. It sets up the case so that when later the product is going through safety case analysis, it is clear what is covered by the design and what…
According to reading material for Institute of Railway Signalling Engineer (IRSE) examination module[1], it says that there are four principle of signalling. They are: I am a bit confused with the word principle, as these doesn’t seem like the main reason why signalling exist. In my view, signalling exists to make money. How? Firstly train…
