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Is the UK the only country that continues to permit and deploy TN-C-S earthing systems?

In a discussion about Diverted Neutral Currents, an contributor (Australia I think) suggested that the problem was that it (DNC) is unique to UK.

I'm not that well versed in international systems of earthing, but it's my understanding that while part of the diverted neutral current problem is because of PME (Protective Multiple Earth), and PEN (Protective Earth and Neutral). And that the the problem is likely to be common to all systems, because there is only one planet earth/ground and we all have to be careful with it when latent and patent faults abound.

I suspect part of the issue is that different folks hear different parts of the story and then project the aspect that's different from their system onto the UK system (given we are reporting it).

Is PME / TN-C-S special to UK?

(discussion was in a Youtube video on ' Loose Neutral Fault Explained')

 

  • Graham, thank you for the clarification. It is always useful to be explicit about definitions.

  • so long as

    .." tied down to gnd with pole base electrodes"..

    I think it's that step that maybe causing the UK/AUS confusion. Because we (UK) have a variety of arrangements with a wide range of ages and states of repair, we are reasonably happy with a bit of flexibility with definitions, yet at times, pernickety/pedantic about distinctions.

    If the Western Australia Beldon case's diagram is to be taken literally, then they are indicating TT at the point of supply (i.e. use a local Earth rod) and likely only a neutral-earth bond at source (off diagram). So in their case  (The YT commenter) they would see PME as needing a true third cable run through the overhead supply to provide a good earth return. (assuming some level of poor western desert distribution condition)

    No doubt a different view of the local pragmatics!

  • plastic bottle supporting the joint.
    locally sourced infill material, surelyThinking... It'll be fine when its filled in and give future archaeologists something to think about
    We have reached " the 21st century plastic layer".
    M.

  • possibly.
    Given that the australian MEN approach has multiple consumer side NE links it is quite different.

    Consider this diagram lifted from an Australian training document. Look how the 2 out building supplies get a 2 wire feed and an earth rod each - which would on its own be TT in the UK, and acceptable, and then they also get an neutral earth bond, which would actually be illegal in the UK. Only outbuilding 3 would be acceptable both here and there. Equally they would have kittens over 'TT'. I had a long conversation about such matters with a NZ sparky last summer as we were both working on the same scout event, and their approach to earthing is more or less orthogonal to ours.

  • Western Power Distribution used to have an environmental impact assessor who would carry out spot checks to ensure that plastic and other waste was not being buried in the holes.

    That hole would have had to be cleaned out before it was backfilled.

  • I've put in an enquiry to the WA govt (email and contact form) to request a copy of the report and asking that their web interface correct the link errors.