Recent content by Guineafowl

Yes, I think we’re into ‘tomahto/tomayto” territory here. What you have is TN-C-S with extra earth rods at the installation end. You may not have N-E bonding along the power poles, but all those houses with rods would make it effectively a PME system. Sometimes, TN-C-S supplies have “belt ‘n’...

Various reasons: - A TN-C-S earth is almost always PME (protective multiple earthing), meaning the neutral must be earthed at multiple points along the final distribution path, establishing a decent equipotential zone. So, it’s a network thing, not simple link in the home thing. - You’d be...

There are pros and cons to every earthing system.

That’s right, a TT earth is the customer’s responsibility, and perfectly acceptable if in spec. The OP requested an engineer visit to assess for TN-S connection to avoid the drawbacks of TT. The visit revealed something separate - that the ancient incoming service cable, belonging to the power...

I’ve just read this bit again - am I missing something, or did those engineers just walk away from a fault? At least part of your cable sheath is floating. What you need is not so much an upgrade, as an urgent repair. If there were a phase-sheath/earth short after the break, would there not be...

I hadn’t heard of that, but I looked it up - on the same site, in two different places, it seems to say two different things (highlighted in red): ***** https://steelprogroup.com/alloy-steel/magnetic/#:~:text=How It Works: Iron is,How Alloying Elements Affect Magnetism? Heat Treatment Heat...

Feeble! Your electric shower would draw 40A or so, for a start. My house has 100A*, and it’s just a rural croft house. I’d say you’ve got a pretty good case for an upgrade. Try to catch them for a quote before the winter, when they’ll all be chasing storm damage. * The fuse carrier is rated...

Heating copper to cherry red, then water-quenching, would soften it, but steel would harden. However, mild steel wouldn’t harden significantly without some extra carbon (eg case hardening). Annealing steel increases its magnetic permeability. Might you be thinking of the Curie temperature...

Remember that of the three earthing options, only TN-S and TN-C-S are the DNO’s responsibility. TT is entirely the customer’s. I’d say they had three options: 1. Convert to TN-S. No, since there’s no N-sheath continuity. Cable is probably too old to trust the integrity of the sheath long-term...

What I said seemed to be the conclusion of Veritasium’s experiment? Time to first current pulse in the bulb was 1m/c seconds, determined by the 1 m straight-line distance from switch to bulb, rather than the 1 second you’d expect as the wires were 1c metres long, assuming a velocity factor of 1.

A ‘negative’ wavefront? Does an opposite wavefront travel the other way around the circuit? I did see those, and the responses from other channels. Interesting, but no substitute for understanding at the deepest levels, of course. More on the level of Feynman’s ‘fun to imagine’ descriptions. A...

The terminals of whatever power supply they have?

Could it be said that the connecting wires have some velocity factor, eg 0.7, and the electric (electromagnetic?) wavefront travels at 0.7c around the outside of the wire, which acts as a sort of ‘waveguide’? Would it also help to think of current not as electrons drifting along like little...

Keep us posted!

The PV installers wouldn’t have seen a problem - 130Ω is within spec for TT. Don’t forget the RCD requirement. I can’t explain why you’re not TN-S - perhaps the earth loop impedance (as it’s called, although I was scoffed at on here for doing so!) was above the 0.8Ω max due to poor connections...