Fuuuuu... My induction hob suddenly burned out and took with it everything on the entire phase, including my oven and solar panels and batteries.... The main fuse from the electricity company blew... >.< I got no ways of preparing food anymore and this is a few days before leaving for vacation.

@miifox It also tripped...

Power is back, they got here to replace the fuse real quick. But obviously the induction hob is toast. And we're actually faced with needing to move up replacement of the entire kitchen to now... Since we are faced with needing to replace 3 built-in pieces of equipement and it doesn't make sense anymore.

@maruno
Wow... That's quite a short!

@StorHaj Some capacitors inside went bang... So probably dead short after. Induction hob is also using 2 phases and who knows what went on inside...

@maruno
Hm... A building's main fuse should take a momentary load of 100 amps per phase no problem... Whatever happened, it pulled a scary amount of current, at least for a few cycles!

In fact, I wouldn't be surprised if you got into the range of current being limited by magnetic flux density rather than transmission line resistance...

@StorHaj I got no idea. And it even was the same phase as our batteries that were on full discharge and the solar panels. So about -10-12A load from those! I do wonder what went on inside, I hope I can take a curious look inside before it goes out.

BTW, our main fuses are 25A and we could occasionally go slightly over it... We suspect this might have also degraded the original fuse over the time.

@maruno
25A main fuses is low, that's for sure... Would explain why they blew. We could exceed that with just two circuits, easily!

@StorHaj Oh, 3x25A is a normal house supply here, used to even be considered 'big' and our older place had 1x35A and I heard of some with an even smaller supply. Getting 3x35A is an option, but a very expensive one and our electricity grid is completely full. There is now a waiting list to enter the waiting list. :D https://data.partnersinenergie.nl/capaciteitskaart/totaal/afname

@maruno @StorHaj meanwhile i got 3x40A for a small apartment o.o

@charlotte @StorHaj That's quite a lot of power for an appartment? My old one had 1x35A and used to have less. All normal groups were 10-12A fused.

Here the normal 3-phase supply is 3x25A and the biggest normal consumer connection is 3x35A. And the price hikes are steep. And infrastructure not made for everyone using this either. :P

3x25A ≈ 500 euro. 3x35A ≈ 2000 euro

@maruno @StorHaj yeah idk how they are getting this much power here, tbh, but the water heater is rated for 20kW

@charlotte @StorHaj Are you talking about a single flat or an entire block? xD

@maruno @StorHaj i got a 20kW tankless water heater on a 3x32A circuit

@maruno @StorHaj the apartment is 20m2 btw

@charlotte @StorHaj That is quite a powerful beast. I just had a 3kW boiler o.o

@maruno @StorHaj 20kW is on the lower end for a comfortable shower with no tank

@charlotte
Yeah, water takes a *lot* of energy to heat up, so doing it fast requires a lot of power, too...

That being said, our tiny flat has eight circuits with 16A breakers, two of these are three phases (one for the oven/hob, one for the boiler). The other six are on a 25A FI, running back to a 100A three phase supply from the grid for the entire 16 unit apartment building that was originally planned for limited occupancy (holiday home).
@maruno

@StorHaj @charlotte The number of circuits here has no relation to the main supply. All our groups are 16A too, you are simply not supposed to turn all of the stuff on at the same time. :D Even the cables in the street are only rates for a certain fraction of the total fused load in the street. Yes our power grid is not dealing well with the energy transition it was never build for. :D

There is internal generation of solar panels and recently batteries that help, but the previous owners had a dumb meter and probably never knew if they went over. Which in winter/night and no battery is easily possible if using the induction hob and oven.

Warm water and heating here is done with gas or a boiler (huge tank, keeping a supply) traditionally and we still got a gas CV. But all the people want heatpumps and recently AC and it simply isn't possible hahaha.

@maruno
Obviously, it's entirely possible to go over 3x100A with everyone running power hungry appliances at the same time here, too... A 250A grid supply would actually be more typical of a small apartment building like this one, but as I said, this building was originally planned as a holiday home with limited occupancy rather than residential. We have managed to blow grid fuses before.
@charlotte

@maruno
And just do we're clear - tankless water heaters wouldn't work on this supply, they need *far* too much power... And heating is provided by an oil furnace. There's no way you'd be able to run anything close to enough heat pump capacity for the entire building without overloading the supply.
@charlotte

@miifox
Fuses are staged: Household fuses have lower current and time rating, building higher, grid even higher. So generally only the home fuse should trigger and spare the rest, but in this case I suspect there was not just significant overcurrent but also significant inductive blind current which, to my knowledge, household breaks won’t catch – only the industrial breaks do.

Unlike active current blind current doesn’t power anything but still heats the wires as it moves, so needs to be limited. Commercial power consumers are actually billed when they “consume” too much blind current so they have an incentive to do blind current compensation, but for household it’s generally not a problem unless something really funky or malicious is happening.
@maruno

@curiousicae @miifox It's all current, why would it not be caught? The grid operator's fuse is also just an old screw in fuse. It also was caught by my own automatic fuse, just both tripped simultaneously.

What I think has happened is that over the years the grid operator fuse derated. We got a smart meter and setup a notification when going over the 25A for the fase, which is relatively easy to do when there is no solar (and now also, batteries are empty) and the induction hob is on and the oven is pre-heating. We then get a notification and can react...

The previous owners had a dumb meter and no batteries, and were a bit simple folk. They have likely gone over 25A by blasting the oven and the induction hob quite often. It won't blow immediately in cases like that, but very slowly.

@maruno @miifox
You’re right sorry, I thought it would cancel out because modern breakers use a coil for short-circuit current detection, but it turns out that’s only for the fast immediate breaker aspect. For the slow-acting overcharge detection they also have a thermal component that works just like old wired fuses, other than tripping before it burns up of course. So yes, it should have tripped or burned out before the gird one.

I stand corrected. I’m a bit surprised the grid operator used fuses, rather than more sophisticated breakers though.

@curiousicae Oh, it may be on purpose so you have to call them to replace it. Cause the price difference between connections is huge, the next connection up is 4x as expensive! :D So maybe they want to maybe keep track of how often you go over it? And mayb against messing with it like taping it or something? Who knows. This normally doesn't happen a lot.

@maruno
Also entirely unrelated question: Is “Zwarte Wolf” = “Zarter Wolf” (Tender Wolf), or is it a false friend association I’m having there?

Like your pictures with them.

@curiousicae I think 'zarter' is German, am I right? It's cute hihi, but a wrong false friend. Zwarte means black! Since they're a black wolf!

Woef is the Dutch word for a barking sound, so 'Zwarte Woef' would be 'Black Woof' or 'Schwarzer Wuff' in German. :) I always named my plushies a bit simple. ^_^'

I am glad you like them and Woef is flattered too.

@maruno
Black Wuff is great too, I canonically imagine them to be a tender black wolfy now though

@curiousicae Ooh, they are very tender and loving <3