Old farm sheds electrics.

[Fleeting]

Read back on the thread. Whole house over-current protection.

Not sure how France has become involved who cares what they do.

 

[John Burns]

The French are way ahead of us, double pole breakers, duel busbars, etc,
We are ahead in plugs and sockets - G Type.

See:

 

[Fleeting]

And this helps the OP how?

 

[Geoff1946]

Why on earth are we discussing France?

Sorry if I side-tracked the chain. I asked just from curiosity.

 

[John Burns]

And this helps the OP how?

It looks like he has a user whole house over-current device. The French have them as standard. How others are doing matters is what a good electrician would want to know. We can learn from them.

 

[Fleeting]

It looks like he has a user whole house over-current device. The French have them as standard. How others are doing matters is what a good electrician would want to know. We can learn from them.

We are not in France it is irrelevant.

 

[John Burns]

We are not in France it is irrelevant.

Anything electrical is relevant. That is your personal opinion, which I do not subscribe to. As I wrote: "How others are doing matters is what a good electrician would want to know. We can learn from them."

In fact the French dual busbar double pole breakers are available here. So very relevant.

Available in the UK, and catching on:

 

[binky]

It looks like he has a user whole house over-current device. The French have them as standard. How others are doing matters is what a good electrician would want to know. We can learn from them.

its a 15th edition board with RCd mai switch feeding another 15th edition board woth RCD main switch, such boards were made redundant due to 'nuisance tripping' hence we ended up with 16th edition boards with main switch and RCD for sockets, As for the French, they dont use CPCs hence all the double pole isolators and RCD main incomers, which at 500mA is enough to kill people which only requires about 50-60mA.

 

[John Burns]

its a 15th edition board with RCD main switch feeding another 15th edition board with RCD main switch, such boards were made redundant due to 'nuisance tripping' hence we ended up with 16th edition boards with main switch and RCD for sockets, As for the French, they don't use CPCs hence all the double pole isolators and RCD main incomers, which at 500mA is enough to kill people which only requires about 50-60mA.

The French do use CPCs. Every modern circuit has a CPC going back to the earth bar in the CU. The CPC is a parallel N conductor as the cpc and N are connected, as in the UK. The vid showing the insides of the French CU I posted with the Wago type of push fit connections shows the cpc's.

The main whole house RCBO is usually 300mA to 500mA - 500mA as shown. It is to protect the system, while the other RCDs, 30mA, are to protect people.

Having a main RCBO, or a whole house MCB, giving whole house over-current protection means the DNO cares not a hoot about diversity, as everything from the main fuse onwards (well meter) is the responsibility of the home owner and now protected. With the home owners now also protecting the DNOs system with an over-current device they are happy.

 

[Fleeting]

How does any of this help the OP?

 

[John Burns]

Whole house over-current protection. You can actually buy the French main RCBOs in the UK. Or make your own with an RCD and MCB in an enclosure.

 

[Fleeting]

And how does this help the OP?

 

[binky]

Whole house over-current protection. You can actually buy the French main RCBOs in the UK. OR main your own with an RCD and MCB in an enclosure.

Why would I want to when I have a board full of RCBOs? Nice to hear the French have updated to cpcs.

 

[Richard-the-Ninth]

Just saying to no one in particular. "Play nicely"

 

[John Burns]

Why would I want to when I have a board full of RCBOs? Nice to hear the French have updated to cpcs.

Many reasons.
1. A main RCBO is a safety net.
2. It protects the system while 30mA RCD/RCBOs protect people.
3. Also it ensures the main fuse will not blow, with an expensive DNO call out, when with all appliances 4. on it will exceed the main fuse's rating.
5. I fitted a whole house main MCB and an S type 100mA RCD in an enclosure in one job as with electric underfloor heating and DHW the 60A supply was pushing it. Diversity said 70A.
6. Looking at the lifestyle of the occupants, diversity usually covers it, but on one instance it may not, then bang, the main fuse is blown.
7. I fitted a Bosch induction hob that operates off a 13A plug.
8. A whole house over-current device will make the DNO not care about diversity as their system is protected, which is all they are concerned about.

 

[SPECIAL LOCATION]

Read back on the thread. Whole house over-current protection.

But the topic is "Old Farm Shed Electrics" (not in France).
So French practices probably offer limited assistance to Allyhme?

We still haven't heard back what the earthing arrangements are?

I am guessing "TT" as its 'Old farm'?

Also guessing each building would need its own Rod..?

Also guessing that just swapping RCD in CU2 for time delayed may mess up the protective measures and disconnection times for
the other circuits local to CU2 via MCB's connected to the proposed RCD replacement..?

But as said we need a bit more info IMHO?

 

[John Burns]

The French are ahead of us. It i worth looking at the best ways. Staying static is no answer.

 

[Murdoch]

The French are ahead of us. It i worth looking at the best ways. Staying static is no answer.

Just stop muddying the waters.

This is totally irrelevant to the OP

 

[SPECIAL LOCATION]

The French are ahead of us. It i worth looking at the best ways. Staying static is no answer.

Complying with BS7671 and/or other UK regulations/guidance is the best way...
Following irrelevant practices in other countries is no answer.

 

[binky]

Many reasons.
1. A main RCBO is a safety net.
2. It protects the system while 30mA RCD/RCBOs protect people.
3. Also it ensures the main fuse will not blow, with an expensive DNO call out, when with all appliances 4. on it will exceed the main fuse's rating.
5. I fitted a whole house main MCB and an S type 100mA RCD in an enclosure in one job as with electric underfloor heating and DHW the 60A supply was pushing it. Diversity said 70A.
6. Looking at the lifestyle of the occupants, diversity usually covers it, but on one instance it may not, then bang, the main fuse is blown.
7. I fitted a Bosch induction hob that operates off a 13A plug.
8. A whole house over-current device will make the DNO not care about diversity as their system is protected, which is all they are concerned about.

DNO will still care about their supply system and what's connected to it, they only allow something like 25 amps per house.

The blowing characteristics of DNO main fuse would require it to be overloaded for quite along time, but if you really wanted to, you could always fit an MCB in an enclosure before the board. I've also never encountered a blown main fuse, at least not caused by overload. My own house is 60A main fuse, nevr been an issue in 20 years. My lcoal DNO fits 80A as standard these days.

I really don't see any need for mA protection before the board, except on TT of course. Meter tails and seprate earth cables are unlikley to ever suffer leakage issues detactable by any form of RCD.

Anyway, its your choice if you want to fit such gear, no harm in doing so.