4 ms·

This is exactly what RCDs are for - with a huge earth leak like that (and therefore L/N imbalance) it would have tripped within milliseconds, before cooking the

This is exactly what RCDs are for - with a huge earth leak like that (and therefore L/N imbalance) it would have tripped within milliseconds, before cooking the grid. I am surprised by how infrequently they seem to be used outside of the U.K. - I’ve just rewired my house in Portugal as it was completely unearthed, and just had fuses, no RCDs.

sib 7y ago
For those in the US, this is what's known as a GFCI (ground fault circuit interrupter).
jacquesm 7y ago
I'm not sure how common these are in an industrial setting nowadays, but back then all big electrical tooling would leak at least a little bit and if you hooked them up through ground fault interrupters those would trip all the time. A typical lathe, mill, plasmacutter or welder (which that particular workshop was full of) would be in the 10KW range with peaks far in excess of that during start-up. I don't remember if we had the office area (where I was working) on protected circuitry or not, that would have been an interesting bit of data. The building still exists, I'm almost tempted to go and have a look. That HV supply was a pretty beefy one by the way, the crocodile clamp that made 'first contact' was gone entirely.
audunw 7y ago
It's required on all new construction in Norway for a decade or so as well. Very common for renovations as well. Norway also just switched to smart meters, which can detect ground problems as well, and supposedly a lot of issues has already been prevented by these being automatically reported. I suppose this is something which is more likely to spread to other countries, as it's not just a safety thing, but also an upgrade that makes your life more convenient, and saves the utilities money in the long term.
foxrob92 7y ago
RCDs are common in Australia. In Western Australia, whenever a house is sold it needs to have an electrical inspection which includes checking if there are enough functional RCDs. Not sure if that's a national requirement or not, but houses I've lived in in Victoria also had RCDs.
ttsda 7y ago
I live in Portugal and have RCDs in my (~7 year old) installation.
mlindner 7y ago
Fuses or breakers? In the US everything is on individual breakers, but only bathrooms have GFCI (RCD) outlets.

sib 7y ago

For those in the US, this is what's known as a GFCI (ground fault circuit interrupter).

jacquesm 7y ago

I'm not sure how common these are in an industrial setting nowadays, but back then all big electrical tooling would leak at least a little bit and if you hooked them up through ground fault interrupters those would trip all the time. A typical lathe, mill, plasmacutter or welder (which that particular workshop was full of) would be in the 10KW range with peaks far in excess of that during start-up. I don't remember if we had the office area (where I was working) on protected circuitry or not, that would have been an interesting bit of data. The building still exists, I'm almost tempted to go and have a look. That HV supply was a pretty beefy one by the way, the crocodile clamp that made 'first contact' was gone entirely.

audunw 7y ago

It's required on all new construction in Norway for a decade or so as well. Very common for renovations as well. Norway also just switched to smart meters, which can detect ground problems as well, and supposedly a lot of issues has already been prevented by these being automatically reported. I suppose this is something which is more likely to spread to other countries, as it's not just a safety thing, but also an upgrade that makes your life more convenient, and saves the utilities money in the long term.

foxrob92 7y ago

RCDs are common in Australia. In Western Australia, whenever a house is sold it needs to have an electrical inspection which includes checking if there are enough functional RCDs. Not sure if that's a national requirement or not, but houses I've lived in in Victoria also had RCDs.

ttsda 7y ago

I live in Portugal and have RCDs in my (~7 year old) installation.

mlindner 7y ago

Fuses or breakers? In the US everything is on individual breakers, but only bathrooms have GFCI (RCD) outlets.