MCB/RCD on consumer unit tripping

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Nice to see you speak like electricians. Most people don't want to see anything new in there house unless it does something they can see. Or it makes them feel safe the ultimate question. 

How do you say its better and easy to solve a problem. RCBOs

 
How do you say its better and easy to solve a problem. RCBOs


If a customer had a single fuse protecting multiple circuits so in the event of a fault they wouldn't have a clue where the cause was coming from...

And it wiped out power to half or more of the property, possibly for several hours if they couldn't reset it easily...

And the fault happened late on a Saturday evening with no local electricians able to attend till Monday to try and get half or more of the property power back on again...

And the labour costs for investigating and tracking down the fault were three or four times more labour intensive as multiple circuits were involved..

They would say..

No way would I want anything as daft as that fitted!!

The same rules apply for RCDs -vs- RCBO's 

A multiple RCBO board is the most logical and cost effective solution..

And any single RCD protecting multiple circuits is the most stupid idea ever.. 

With the exception of possible an outbuilding, (Shed/Garage/Workshop), with a single RCD board..

Guinness

 
Nice to see you speak like electricians. Most people don't want to see anything new in there house unless it does something they can see. Or it makes them feel safe the ultimate question. 

How do you say its better and easy to solve a problem. RCBOs
As per the post by Specs above, and a single or dual RCD board does not comply with clause 314.1 of BS 7671

 
As per the post by Specs above, and a single or dual RCD board does not comply with clause 314.1 of BS 7671
hit, nail and head springs to mind BUT try discussing this with the typical person with a Screwfix catalogue on their kitchen table - all they want is the cheapest solution.

my tact is to quote for a RCBO board I will supply and fit  or I won’t do the job

 
hit, nail and head springs to mind BUT try discussing this with the typical person with a Screwfix catalogue on their kitchen table - all they want is the cheapest solution.


Exactly this, even wholesalers are still pushing them though, my local has a pile of schneider dual RCD's for around £70 each. 

As a budget upgrade against a very old non RCD board they offer a major improvement but in my opinion stop them being available and work on getting the RCBO prices down. Decent brand RCBOs are still north of £20, get them down to around £10 and they'd become an affordable option and most people would be converted. 

Unfortunately if they go with this AFDD rule in amd 2 there'll be very few boards getting changed by legit sparks, the no cert DIY Dave changes will be rife though. 

 
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Unfortunately if they go with this AFDD rule in amd 2 there'll be very few boards getting changed by legit sparks, the no cert DIY Dave changes will be rife though. 


Whilst I have some sympathy for the manufacturers I see absolutely no mandatory requirement for fitting AFDDs in the next 10 years .....

and I’ve been asking recent customers how they would feel about a £1500 fuseboard change (or more as I’ve replaced a few big unit recently) and let’s just say they struggle to copy with £500 to £650 so non compliant installations will become the norm

3 years to early retirement and counting down as the mortgage shrinks

 
With all the above in mind and I do agree(don't know how to quote yet sorry). 

Clients do always go for the cheapest method and its understandable. while the other methods RCD split boards are being sold. etc...

The leakage is I do agree getting worse but I will bet there will be a new restart at some point with the old Earth Leakage devices. 

 
(don't know how to quote yet sorry). 
below each post is the word “quote” - select this and then add the quote to your new post - you can also edit / remove parts of the post you are quoting but remember when you add you thoughts to click outside the quoted post or it can get confusing

hope this helps

give it a try

 
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Whilst I have some sympathy for the manufacturers I see absolutely no mandatory requirement for fitting AFDDs in the next 10 years .....

and I’ve been asking recent customers how they would feel about a £1500 fuseboard change (or more as I’ve replaced a few big unit recently) and let’s just say they struggle to copy with £500 to £650 so non compliant installations will become the norm

3 years to early retirement and counting down as the mortgage shrinks


I saw a video of a guy who'd built his own testing unit for AFDDs, fair enough it wasn't strictly scientific, and found they didn't work unless there was (if I remember correctly) at least a 1.5kw load on the end of them. He was using a wylex board he'd installed, fully loaded with AFDDs, cost somewhere in the region of the figure you've quoted. Frightening money when their effectiveness is questionable. 

 
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I saw a video of a guy who'd built his own testing unit for AFDDs, fair enough it wasn't strictly scientific, and found they didn't work unless there was (if I remember correctly) at least a 1.5kw load on the end of them. He was using a wylex board he'd installed, fully loaded with AFDDs, cost somewhere in the region of the figure you've quoted. Frightening money when their effectiveness is questionable. 
IIRC they need a minimum load of 2.5 kw to use - which really renders them useless in most modern properties except maybe the kitchen ring and oven

Which to me is a totally pointless reason to include them, even less so to make them mandatory

the total load for our house is about 350 watts .... so a fault would need to occur on a circuit with something like a kettle being used, or the tumble dryer 

 
IIRC they need a minimum load of 2.5 kw to use - which really renders them useless in most modern properties except maybe the kitchen ring and oven

Which to me is a totally pointless reason to include them, even less so to make them mandatory

the total load for our house is about 350 watts .... so a fault would need to occur on a circuit with something like a kettle being used, or the tumble dryer 


especially when the draft said something like 'on circuits below 32a' so your 32a sockets & 32a cooker supply wont have a requirement to have one...

 
pretty much. looks like i may have to start installing more 32a circuits even if 20 or lower is suitable... shame about the reg wanting lamp holders on 16a max, otherwise it would be lighting circuits wired in 4mm and on a 32a breaker

 
pretty much. looks like i may have to start installing more 32a circuits even if 20 or lower is suitable... shame about the reg wanting lamp holders on 16a max, otherwise it would be lighting circuits wired in 4mm and on a 32a breaker
Wire all 32a ccts  from Board.......switched fuse Spurs to fuse down for lower loads?

and a single or dual RCD board does not comply with clause 314.1 of BS 7671
I've argued this from day one, particularly with the NICEIC AE

i may even have mentioned it on here once. Or twice

 
pretty much. looks like i may have to start installing more 32a circuits even if 20 or lower is suitable... shame about the reg wanting lamp holders on 16a max, otherwise it would be lighting circuits wired in 4mm and on a 32a breaker
Its's not the circuit rating, its the socket outlet rating!

 
Its's not the circuit rating, its the socket outlet rating!


been a while since i read it and dont have a copy of it to look back at... knew it had something to do with 32a, thought that was the circuit rating

but if that is the case, does that mean circuits without sockets are exempt? or was there another one requiring it there too?

 
I saw a video of a guy who'd built his own testing unit for AFDDs, fair enough it wasn't strictly scientific, and found they didn't work unless there was (if I remember correctly) at least a 1.5kw load on the end of them. He was using a wylex board he'd installed, fully loaded with AFDDs, cost somewhere in the region of the figure you've quoted. Frightening money when their effectiveness is questionable. 
That was probably John Ward (JW) his tests were flawed unfortunately.

The AFDD concept is somewhat different to what we are taught to expect & install.

IIRC they need a minimum load of 2.5 kw to use - which really renders them useless in most modern properties except maybe the kitchen ring and oven

Which to me is a totally pointless reason to include them, even less so to make them mandatory

the total load for our house is about 350 watts .... so a fault would need to occur on a circuit with something like a kettle being used, or the tumble dryer 
It’s 2.5A, Wylex/Crabtree are down to 1.5A

 
32a sockets all over houses are going to look really out of place
The issue is that this time it will include industrial and commercial.

So machinery with designed in earth leakage which is on plugs for quick movement, as you find in the food industry for cleaning or line re-configuration (both very common) are now going to have issues...

If it gets through the option for RA is being removed.

 

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