relocating a 17th ed db

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Hi Guys and girls
just seeking the advice of the wise please.

Im quoting for some bathroom works, extract fan, spot lights etc but the customer has asked about moving the DB.

So the situ is there are 2 DBs both of plastic structure, 1 is a 17th 16way dual RCD and the other is just a 5way and all circuits on MCB's.
The dual rcd db was installed when home had extension works and has capacity to install the existing circuits on but the electrician/builder wanted to charge the earth to merge both boards so never got done.
customer has asked if I'm able to merge as she would like to put the unsightly installation in a cabinet.

so my questions are:
1: Can i merge both as this would provide the additional protection needed as ill be making alterations to the existing bathroom circuit? Obvs if the non rcd circuits test out fine before merge.
2: would it be compliant to relocate a plastic DB if no new circuits are being added to it? even thou i kinda would be adding new circuits but are exiting to the whole installation......if this makes sense

in brief:
merge a non rcd db to a dual rcd db of plastic material to a new location (literally moving over 500mm) and making alterations to existing circuits.

TIA
Dean
 

Sharpend

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So they are all on same supply as larger board. Then you can transfer but it will increase chances of nuisance tripping with additional Elc, as Murdoch suggests a new metal board with RCBO’s would be best option long term.
 

Mike P

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Surely Any work involving the installation of new circuits to a board means that it must comply with the latest regs
ie. New metal consumer unit with current protection per regs. You may be merging boards but it is still an installation!
 
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It’s perfectly acceptable to add new circuits to existing plastic fuseboards


Surely Any work involving the installation of new circuits to a board means that it must comply with the latest regs
ie. New metal consumer unit with current protection per regs. You may be merging boards but it is still an installation!
 

steptoe

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It’s perfectly acceptable to add new circuits to existing plastic fuseboards
It's also , imo, perfectly acceptable to install a new plastic CU in a domestic installation under certain circumstances.
I don't understand all this 17th edition boards and stuff,
Dual RCD boards don't comply with the current regs, but folks still install them.
 

Fleeting

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There is no such thing as 15th, 16th, 17th, 18th or any other edition flavours for a distribution board and the Regulations have never stipulated specific format layouts for a distribution board so why would they start now.
 

binky

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It's also , imo, perfectly acceptable to install a new plastic CU in a domestic installation under certain circumstances.
I don't understand all this 17th edition boards and stuff,
Dual RCD boards don't comply with the current regs, but folks still install them.
the recomendation is 'fire retardent' not metal, and that requirement can encompass plastic boards, and the requirement ofr fire retardent applies to high fire risk areas, such as hallways / understairs cupboards, so it's still perfectly legal to fit a plastic board in something like a utlity room at the back of a house.
 
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As I understand it any new circuit does require rcd protection. It's if your just extending an original it doesn't?????

I started fitting rcd spur units next to the board to protect lighting circuits when working in bathrooms etc.

Or I've installed separate rcd units if the board doesn't have any to ensure compliance.

The biggest problem is locating mcbs for older boards. That can cause a board change or 2nd board install more often.
 

Fleeting

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Not every circuit would require additional rcd protection in a dwelling or anywhere. For example an immersion heater where installed in such a manner it dies not require it. RCD spurs are not recognised by BS7671 as a suggested means for additional rcd protection.
 
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RCD spurs are not recognised by BS7671 as a suggested means for additional rcd protection.


IIRC these have reappeared in the electronic version of the `18th Edition, but for those with the paper books they don't appear.

Maybe somebody with electronic access to the regs could take a look
 

Dranok

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There is no such thing as 15th, 16th, 17th, 18th or any other edition flavours for a distribution board and the Regulations have never stipulated specific format layouts for a distribution board so why would they start now.
My favourite bugbear since the 17th came out! It goes down as a C3 on so many of my reports: "314.1 Every installation shall be divided into circuits... to i) avoid hazards [like every light in the building going out simultaneously and workshop equipment stopping mid-task or a Stannah stairlift stopping half way] and minimize inconvenience in the event of a fault [including trivial ones like a bulb blowing]"

The way I see it, "17th Edition" boards are so named because when they came out they specifically failed to meet the requirements of the new 17th Ed Reg's. It meant that domestic boys (house-bashers) doing re-wires, and being asked to keep down the cost by not installing RCBOs, had to carefully wire up a split-load DB to ensure sockets upstairs and lighting downstairs were one side and vice versa, and central heating was one side and electric shower or immersion heater the other, so that if a fault occurs keeping upstairs off, then the householder could still take up and plug in a standard lamp, and they still could wash in hot water, and other common sense matters. So along I come to inspect and no such allowance has been made: Mr Builder-cum-Sparky has neatly put the ground floor one side and the top floor the other, or all the heavy stuff close to the incomer and all the lighting the other side, or some other pretty but illogical arrangement.

If the IET had stamped on manufacturers mis-branding and reported wholesalers to the DTI under Trade Descriptions, then people would have been far more inclined to install RCBOs everywhere from the beginning, the manufacturing demand would have skyrocketed, and within 10 years the price of them would have been 50% more than an MCB. We do it to ourselves most of the time -- we accept these annoyances instead of balloting those "in charge of change" in our industry. Hey guys! We *are* the industry! If you see something is wrong, tell the IET and the ESC; the more we do, the more it will be logged and considered for future editions.

"That was a public service announcement on behalf of the Electrical Safety Commission Bigwigs..."
 
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