Well, that’d be very expensive. Plus I’d need at least twice the size of my board!
I’ve to take a look, never seen such element in France… And they are taking only one unit!
Is that not overkill?
As you can see, I’ve a main 30mA, and for each group another one. From time to time, it can happen that both a sub-30mA and the main trigger.
I’ve already tested, they trigger mostly around 20-25mA.
A Type-A RCBO are only about £10-£20 (17 - 23 EUR), they take up a single module so you would actually gain space in your board since you wouldn’t need to the double module RCDs. They used to be expensive, but they have come down in price a lot.
The main advantage of RCBOs is if there is a residual current fault on a particular circuit only that circuit will trip, it make it easy to identify the circuit with the fault and avoids power loss to other circuits. It’s also an advantage to avoid nuisance tripping due to accumulative leakage from DC-DC converters etc since each circuit has 30mA to play with rather than 30mA split between several circuits.
I’ll have to search for that if it’s available in France…
Ok, looks like they do exist from Hager/Legrand, but for the French market, they’re 2 units wide.
What do people do to notice when a single RCBO trips? When a “whole board” RCD trips it’s easy to notice because everything goes dark. But if only the RCBO on the Freezer trips…
Sure, that’s a drawback too!
There’s no perfect solution, except you’ve unlimited budget to wire the installation like in the industry.
Auxiliary alarm contacts to fit an RCBO exist, e.g. https://www.se.com/au/en/product/A9A19802/acti9-ic60-rcbo-auxiliary-contact-1sd-ac-dc/
This could be used singly or together with others to sound an alarm when one or more RCBO in the installation has tripped.
I guess it would be unusual for a freezer to have its own circuit, there would usually be other things plugged into the same radial that would make it obvious that it’s tripped. There is definitely an argument not to put smoke alarms on their own circuit for this reason, putting smoke alarms on the bedroom light circuit makes sense to me.
I would definitely run smoke alarms on battery, and even better, in a mesh network, so if one triggers, all others trigger too. I’ve that at home.
Hard wired mains powered interlinked smoke alarms are mandatory on new installations in the UK. They have a battery backup, so will still work in a power outage
Then ok!
England and Wales, yes mains powered. Scotland (different Building Regulations) they can be battery powered. There also has to be a heat sensor on the Kitchen. Still interlinked.
Looks like these regulations are much more in advance than in France.
In France, only one single smoke detector is mandatory in each flat/house.
From my POV, that’s far from enough, just one is somehow useless.
I’ve one in each bedroom, one in the cave, one in each “open space room”.
All on battery but as a mesh, so if the one is the cave triggers, all others trigger after less than 5 seconds.
That is basically the Scottish design, but in addition a heat sensor in the kitchen.
Thanks @Robert.Wall I haven’t understood the product information on that link. Does this device have some simple relay contacts that change state when the RCBO trips, or is it more complicated with some serial data output that needs to be decoded?
The link was an example - you need to go to the manufacturer of the RCBO that you have, and see if they have auxiliary alarm contacts for your RCBO, and see how they fit. If it takes up 1 position, you could be looking at replacing your consumer unit, which would be expensive.
I think you can be reasonably certain that one make of aux contacts won’t fit another make of RCBO.
The Schneider one has changeover contacts (if you look carefully at the image - on the side is a diagram - also in the instructions), and the moving contact will be mechanically connected to the actuating lever of the RCBO, so you can have the contacts open when the RCBO is normal, and closed when the RCBO is tripped, or vice versa. They are without doubt real metallic contacts, though looking at the installation instructions, there is a version that does send data (and without doubt it will be in a proprietary format 
).
Thanks @Robert.Wall : A dry “relay” sounds good news and potentially easy ish to integrate into my existing Victron kit which has some alarm signalling capability 
The simplest would be a 6 V battery and a bell or buzzer!
But make sure whatever you get is compatible with your existing kit, unless of course you are replacing it.