In my reply I will use CE to refer to CE & UKCA marking.
I will also use LVD to refer to the Low Voltage Directive and the Electrical Equipment Safety Regulations.
I will use harmonised to refer to both harmonised to the LVD and designated to the EESR standards.
As far as I am aware, in mainland Europe, it is rare if not unheard of to have an 80 or 100 A incoming 1ph mains supply; most are circa 30-40 A, 1 or 3ph.
A consumer unit falls under the LVD and must be CE marked as an assembly.
The normal route for this is by following product standards. The legal link between product standards and the LVD is much stronger than BS 7671 & EAWR because of how the product standards and the legislation are constructed.
The legislation states that compliance with a harmonised standard will ensure compliance with the EHSRs of the legislation.
The harmonised standards state that if certain clauses are met, then the EHSRs will be met by those clauses.
Now, whilst standards are voluntary, it is rare for a manufacturer to not follow standards because the level of work required is inordinate in comparison to the standards route.
Ergo, 99% of products are designed and manufactured to the product standards (assuming compliance).
A consumer unit has a product standard, the EN 60439, now EN 61439 series.
In there is a national annexe for the UK, Annexe ZA.
National annexes to harmonised standards are legitimate.
The UK has a national annexe because of the allowed 16 kA fault current at the origin of a normal domestic installation.
Apparently, the 30 - 40 A mainland European supplies do not have such fault current levels IIRC, it's been a while.
As a result, an assembly placed on the market in the UK must withstand this 16 kA of fault current without damage and without collateral damage.
Therefore, the manufacturer (placing the equipment on the market) must ensure that the assembly meets this requirement.
They can only do that by testing. They can only do that by testing their products.
Therefore, if you fit a different product, the type or partial type testing by the manufacturer to prove compliance with the LVD is no longer valid as the assembly is a new product.
You become the manufacturer of this new assembly.
The burden of proving compliance with the LVD falls upon you.
Few sparks have professional indemnity and product liability insurance for product design, manufacture, and supply.
So firstly, you may be working uninsured.
Next, you have created a product and placed it on the market without CE marking it; that is a criminal offence.
The original CE mark is invalid because of your modification.
The hazard is that there is no way to prove that the assembly created meets the requirements of annexe ZA in the standard.
You must follow this route to compliance because that was the route taken for the base product you modified.
Your only route is to follow the requirements of the product standard.
Remove and test the assembly, then refit it, which would be impossible because the test is destructive, so you would not have a DB to refit!
Therefore, there is a reason behind the no mix and match in the UK, and there is a reasoning behind why mainland Europe is different.
The choice is clear; it is up to the individual and their risk aversion.
If you are risk averse, then you don't do it.
If you don't care, then you mix and match, knowing that the job can never comply with BS 7671 and can never comply with, the LVD and is a breach of product legislation; that is, you are committing a criminal offence.
You can say that it is protectionism by the manufacturers, but then again, why should they take the liability for the actions of others?
Would any spark here accept liability for their work which had been modified or changed in some way by a third party, or would you say that as it has been modified, it's no longer my liability?
I know what I would be saying.
It is the same for the CU manufacturers. Why should they take liability for produces (rouge breakers) fitted to their assembly by persons whose competence is unknown to them?
You could argue that the product standard for circuit breakers should be enough for compatibility, but the fact is it is not.
If it were, we would have companies making the cheapest circuit breakers to fit, and it would be a race to the bottom concerning quality and safety for consumer units. It's approaching that now, but that's another topic.
This would reduce safety and detract from product innovation.
Question what I have written, but any personal attacks will be reported for moderation.
These are the facts; if you don't like them, that is not my fault, so don't attack me.
I don't like this situation, but, having gone through the legislation and the standards in detail and done expert witness work on product standards and legislation, it is difficult to get away from how they are structured.
