Lap mcbs

[Eartheo]

The bungalow I’m in had a new Lap consumer unit fitted 7 years ago. I wanted the shower 40amp mcb upgrading so a larger shower could be fitted. An electrician told me this cannot be done as Lap was a Screwfix part and they no longer did mcbs for this and my best bet would be to change the whole consumer unit as you cannot mix mcb manufactures in a consumer panel. Is this correct or is it just over hype, as I was always led to believe that if the mcbs were to British standards it was ok.

 

[brianmoooore]

Personally I wouldn't purchase mcb's/rcbo's from eBay, only a reputable supplier

I wouldn't either, in normal circumstances, but when it's a choice between a £300 unnecessary board change, or a £5 ebay MCB.........

 

[Deleted account]

Agree with above. I do not go down the second hand mcb route.
Your options are. New consumeunit as per your sparkies advice, or fit a new mini consumer unit next to your current one for the shower only.

You can never guarantee a true fit or match with another brand or make. So I don’t do that either.

 

[Deleted account]

I wouldn't either, in normal circumstances, but when it's a choice between a £300 unnecessary board change, or a £5 ebay MCB.........

For me the option I give customer is the board change. Not the £5 eBay second hand jobbie.

 

[LastManOnline]

You can never guarantee a true fit or match with another brand or make. So I don’t do that either.

I understand and fully agree with not mixing different brands. Is it forbidden in UK or simply not recommended?
Secondly, what's the main reason?

 

[LastManOnline]

Agree with above. I do not go down the second hand mcb route.

Completely agree. A device that costs a fiver but plays a vital role. Also unlike rcd, s we can't test beforehand how well it works. We are completely reliant on the manufacturer,s reputation

 

[loz2754]

I understand and fully agree with not mixing different brands. Is it forbidden in UK or simply not recommended?
Secondly, what's the main reason?

It's written in the regulations. The reason has been stated already, namely, that manufacturers type test their own products and certify as safe to use. If we introduce different brands, we become responsible for certifying that the configuration we have devised is safe for use.
If anything were to go wrong, we could be held accountable.
I have seen the (badly burned consumer unit almost caused a house fire) results firsthand on several occasions.

 

[pc1966]

For electrical inspection the "Best Practice Guide #4" has it is either C3 "improvement recommended" or C2 "potentially dangerous" depending on the particulars. The C3 section has:

Mixed branded switchgear components within a consumer unit or distribution board where:

• there are no signs of thermal damage to component or associated connections
• the enclosure/assembly hasn’t been modified to allow installation of the component
• the component is securely fitted and all connections are adequate
• correct manual operation of the component
• direction of use of toggles/switches is the same as existing devices

Note: If any of the above criteria is not met, this would warrant a code C2 classification to be recorded.

As mentioned above, the real issue is the bus bar not being properly clamped due to the variation in MCB terminal locations and bus-bar design leading to a real risk of overheating and a fire.

 

[LastManOnline]

It's written in the regulations. The reason has been stated already, namely, that manufacturers type test their own products and certify as safe to use. If we introduce different brands, we become responsible for certifying that the configuration we have devised is safe for use.
If anything were to go wrong, we could be held accountable.
I have seen the (badly burned consumer unit almost caused a house fire) results firsthand on several occasions.

Perhaps I am missing the point but if I have a Hagar B type 20 amp alongside a Wylex B type 20 amp, in what way does that constitute a risk?. Obviously it's problematic for the buzz bar and hence unsuitable, but where exactly does the danger lie?

 

[andyb]

Perhaps I am missing the point but if I have a Hagar B type 20 amp alongside a Wylex B type 20 amp, in what way does that constitute a risk?. Obviously it's problematic for the buzz bar and hence unsuitable, but where exactly does the danger lie?

The danger lies in badly fitted components, but the main reason that you don't put other manufacturers parts in someone else's board is that if it is a Hagar board, for example, it will no longer be a Hagar board once you have fitted your Wylex mcb, it becomes a LastManOnline manufactured board. And as such you take full responsibility for the design and manufacture because you made it.

 

[stevethesparks]

Obviously it's problematic for the buzz bar and hence unsuitable, but where exactly does the danger lie?

I would have thought that you have answered your own question there???

 

[LastManOnline]

I would have thought that you have answered your own question there???

Yes, I just wanted to be clear on what exactly the issues were from the UK point of view. It comes down then to to adapting a busbar to suit a, make its not designed for. Fair enough. But the usual solution to that issue is simply not to do it. Instead loop a 10mm from the existing Wylex to the new hagar mcb, s? Problem solved surely?

 

[Micktw68]

That is correct you cannot mix and match mcbs. A standalone 1 way board with rcd would be sufficient, however if u had a LAP consumer unit in my house I'd certainly be looking to change it ASAP. Their mcbs, rcbos and boards are probably the worst I ever came across.

Running Chint a close second place.

 

[telectrix]

Running Chint a close second place.

Hmmm., I fitted a Chint TPN DB in an office 11 years ago. populated wuth 24 single phase RCBOs. loads of heaters and IT gear. had 1 call back to a tripping RCBO. was a fault on the socket circuit. no other problems at all.

 

[LastManOnline]

Yes, I just wanted to be clear on what exactly the issues were from the UK point of view. It comes down then to to adapting a busbar to suit a, make its not designed for. Fair enough. But the usual solution to that issue is simply not to do it. Instead loop a 10mm from the existing Wylex to the new hagar mcb, s? Problem solved surely?

So in short, you can mix and match. You just need to do it correctly. However it would, nt look very professional. But let's be clear, on the evidence presented here so far there are no justifiable reasons to say "you can't mix and match"

 

[nicebutdim]

Is the answer to be found within BS EN 61439-3:2012?