Do 16 amp plugs/sockets have fuses?

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gregmcateer

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Well spotted :)
Now you know what you are looking for, you can see that a 16A MCB can be fitted in a one or two slot plastic box (like a garage consumer unit but much simpler (and only £10 to £20)) with a couple of inches of round plastic conduit down to a switched CE socket.
Don't use the very cheapest surface mount sockets. Pay £30 and get a gewiss, lewden or some other brand of switched 16A socket. These lock the plug in place while the power is turned on.
Two reasons. 1. It stops the plug being pulled out by accident. 2. It stops the plug being pushed into a live socket and a machine possibly being started up when it wasn't intended and may not be safe.

You're on the right track now.

Sideways,
That info is super helpful - thanks for sharing your knowledge.
I'm familiar with the' garage' dis boards, but what are the little single fellas you describe called? I'm struggling a bit to find one on the web.
Many thanks in advance
Greg
 

Sideways

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Here's the first example I could find :

Plastic is good. No rust and easy to knock out the holes. Also you don't need to earth the enclosure as you mist with a metal box.
Plastic cover over the breakers is good. Rubber seal helps keep out dust and damp giving a good IP65 or IP66 rating.
DIN rail (top hat rail) is a metal strip fastened to the inside back of the box that the MCBs clip onto.
2, 3 or 4 slot sizes are all compact and cheap. Take your pick. Single slot is enough for one 16A MCB, but 3 would take an RCD plus separate MCB should that ever be needed.

Wylex are decent and available at Screwfix or Toolstation.
Siemens, Schneider and many others make equivalent products at similar prices. You local CEF will probably have them in stock.

Start keeping eyes open for a right angle plug in 16A CE style at a good price. They are less common but help the cable to hang nicely from a switched socket, without sticking out as far as the normal ones pictured in my earlier post.

Cheers
 

NetBlindPaul

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The issue with plastic enclosures is compliance with the wiring regs.
Almost none comply.
So unless the workshop is sufficiently detached from the main dwelling then it is doubtful that a plastic CU enclosure can be used.
DIY or not, the insurance company may have a view of the requirements for compliance with the wiring regs.
 

Sideways

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Paul is correct if this were a consumer unit. But unless something changed in the last version of the wiring regs (blue book) that I don't have a copy of, a subsidiary box holding one MCB for one socket is not a consumer unit and I'm pretty sure there is no requirement in the regs for it to be metal.
If I'm wrong there are 2 and 3 module enclosures in metal sold for shower connections at not much more cost.
 

MikeJhn

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I think the regs say "Non Combustable" not metal, how many MCB's/RCD's must an enclosure have to make it a consumer unit? Most Garage three way units I have seen recently are all Metal.
 

MikeJhn

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Having two pole protective devices would only add cost and no added benefit to the domestic user.

But do make it so much easier for fault finding and testing. 🥳

Modern thinking is all RCBO boards, dual pole gets over the wrong neutral bar problem that some seen to get. 🥴
 

Woody2Shoes

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Paul is correct if this were a consumer unit. But unless something changed in the last version of the wiring regs (blue book) that I don't have a copy of, a subsidiary box holding one MCB for one socket is not a consumer unit and I'm pretty sure there is no requirement in the regs for it to be metal.
If I'm wrong there are 2 and 3 module enclosures in metal sold for shower connections at not much more cost.
Yes, it's not unusual, or apparently against current regs, to have a 'smart' meter in a plastic enclosure feeding a cu which must be metal!
 

Sideways

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And 100 Amp isolators fitted before the CU are routinely fitted in plastic boxes.
The requirement for non combustible consumer units came in with Amendment 3 of the Yellow book, and metal is / was just the easiest way for manufacturers to comply with that.
The change was driven by statistics from the (London ?) fire services about the number of home fires attributed to overheating in the consumer unit.
Most houses and flats have just one box where the main isolator and majority of the circuits terminate and circuit protection is provided. It is designated a "consumer unit" in the domestic setting and the amendment to the regs about non combustability etc was written with reference to "consumer unit" where many connections are terminated in one place and the chance of a loose / high resistance / hot connection is greatest. It did not apply to all enclosures in general used to house MCB's.
But I don't have a copy of the latest regs and stuff like this does change. Electricians have to keep up to date. I just did their City and Guilds exams for fun and education when I retired. As it happens, just a year before the regs were updated :)

Note that adding a spur to an existing circuit is "minor works" that doesn't need to be notified to building control, but absolutely needs to be done correctly and safely. Paul's comment above which I can't definitively answer is a good example of why you can use the internet to educate yourself on this stuff but should go to the professionals when your life or insurance depend on it !
 
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Spectric

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I think like most of the regs they can be open to interpretaion, but it is not just the enclosure needs to be non combustable because the actual term used is " to contain a fire" which also requires all cable entry / exit points are also sealed in order to comply which is what gives the most issues in undertaking.

The main issue of ambiguity is the term " consumer unit" which in my books I class as any enclosure that contains a protective device and not only the main board in a property which some are using. For the consumer unit these glands are a good start 40mm Tail Kit Gland - 2 x 25mm Tail & 1 x 16mm Earth Cables | Wiska (WKTP40R32 / 10106245) but are plastic so these fully comply 40mm/32mm Brass Tail Kit - 2 x 25mm Tail & 1 x 16mm Earth Cables | Wiska (WKTKB40R32) but are £18 compared to £5.

Luckily for me most of what I did was industrial where metal enclosures and trunking have always been the norm and you don't have to sort out a dangerous mess that someone has attempted by self learning and without the right test and measurement equipment.
 

Robotstar5

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Interesting discussion, I class my workshop "CU" as a distribution board (DB1) as it's a sub board fed from from my house CU about 30 metres away. I fitted 16A and 32A switched sockets "just in case".

GarageCU0420_08_resize.JPG
 

Sideways

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At the risk of digressing and for the folks still interested in all this, here's what the IET (the folks who publish the wiring regs that apply everywhere in the UK) said in explanation when this non flammability thing was introduced.
It nicely demonstrates how the folk writing the regs realised that there could be arguments over interpretation and they tried to anticipate the obvious ones.

The scope was " consumer units and similar switchgear assemblies ".
"
The phrase ‘similar switchgear assemblies’ in Regulation 421.1.201 means those assemblies used for the same fundamental application as a consumer unit. A consumer unit is defined in Part 2 of BS 7671:

‘Consumer unit(may also be known as a consumer control unit or electricity control unit). A particular type of distribution board comprising a type-tested co-ordinated assembly for the control and distribution of electrical energy, principally in domestic premises, incorporating manual means of double-pole isolation on the incoming circuit(s) and an assembly of one or more fuses, circuit-breakers, residual current operated devices or signalling and other devices proven during the type-test of the assembly as suitable for such use.

An example of a similar switchgear assembly is a three-phase distribution board that is intended to be operated by ordinary persons. This would have to have isolation that interrupts the three incoming line conductors and the neutral, rather than just double-pole isolation as mentioned in the above definition.
"


This is rather more elaborate than just an MCB in a box to protect one outlet. An MCB doubles as both a functional switch and an isolator if locked off, but it's not a double pole isolator. It doesn't break both the live and neutral connections. One MCB in a box doesn't sound like a consumer unit to me. I think the writers of the regs found the best words they could to cover large through small versions of what we all expect. The big red switch, one or more breakers, plus optional RCD's, and / or combined RCBO devices.

Then, is it still a "consumer unit or similar" if it's in a shed or garage ?

"
Consumer units in outbuildings or on the outside of a building
Regulation 421.1.201 uses the term ‘premises’. The question could therefore arise: do the requirements of the regulation apply to a consumer unit or similar switchgear assembly within an outbuilding such as a garages or shed, or mounted on the outside or a building?

Some dictionary definitions of ‘premises’ are ‘a house or building, together with its land and outbuildings’ and ‘the land and buildings owned by someone’.

However, Regulation 421.1.201 was principally introduced to cover the interior of a household building and any garage or other outbuildings integral, attached, or in close proximity to that building.

Doubt could exist about whether or not a particular outbuilding could reasonably be considered to be in ‘close proximity’ to the household building. A way of resolving this might be to make a judgement of the likelihood that fire originating inside the enclosure of a consumer unit or similar switchgear in the outbuilding might lead to the outbreak of fire in the household building or in any outbuilding integral or attached to it. Relevant factors to consider about such an outbuilding might include whether or not that building or its expected contents are highly combustible.

Regulation 421.1.201 is not intended to apply to a consumer unit or similar switchgear assembly that is not within a building, such as a consumer unit mounted outdoors on the outside of a building.



Now you see why you're paying your sparky the big bucks :) If he interprets stuff like this wrong and is unlucky, the cost of your new house could end up on on his business insurance. No wonder some will play safe and charge you for a tin box every time, just in case.

As a side note, Engineers, Lawyers, all sorts of specialists are sometimes, but by no means always, blessed with the skills to write clear, unambiguous English. When they don't achieve clarity, we all get into arguments like this and because of the cost and consequences of litigation, the ordinary tradesman has to play safe and we pay for over specified kit that was never justified by the facts. Regulation is good when it pushes standards up. Like law, it's bad when poorly drafted. Sometimes less is better.
 
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Spectric

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I suppose you could take it from an entirely different viewpoint, one that I think many seem to unwisely take and that is the 7671 IEC electrical regulations are not mandatory, you do not have to follow what is in effect best practice and guidance. The part many do not get is that when something goes wrong and you fry someone then if the installation or wiring is found to be non compliant with said regulations and even if you are fully qualified then you better have a solid waterproof explanation as to why you did not follow the regs, they are a double edged sword. I always ensured all my work could not be questioned, and was OTT rather than cut corners to cut cost to get work. The thing I most dislike is the term domestic installer, if you want a job done right and by someone who not only can but fully understands why then ensure you use an electrical engineer, domestic installers are just a cost saving initiative for the new build market.
 

deema

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Many years ago I used to be Involved with developing the regs. What I will say, is that it’s incredibly difficult to write something that is both understandable by the average sparky and covers ever single conceivable eventuality and available technology at the time of writing.
 
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gregmcateer

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Thank you to all the sparky knowledgeable folk for their input - confirms what I already thought - best to just get a qualified electrician in - cost a tad more, but at least it should be correct and more importantly, safe.
Cheers
Greg
 

Spectric

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by the average sparky
I will say that once upon a time sparkies turned up on sites wearing suits and were looked upon as the clever people.

best to just get a qualified electrician in - cost a tad more, but at least it should be correct and more importantly, safe.

If you get a qualified electrician in then the job will be correct and more importantly you and your family will be safe, there is a lot more to what may seem a simple wiring job and at the end of the day you won't have the test equipment to actually confirm everything is safe and under a fault condition will fail safe so a sparky will be a very good investment. Both myself and sideways have tried to explain the complexity of an electrical instalation so all the best and once done you can get on with enjoying what we are all here for and that is our woodworking.
 
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deema

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The use of language, or the ability to use language is not IMO a good reference to intellectual capacity. The use, terminology selected and grammar has to reflect the entire spectrum of people who will qualify to work in a particular profession. It must also reflect the needs of those who may utilise the documents in a legal arena so they have to be sufficiently proscriptive. It was a very serious issue finding the correct language to use. After all, we have a whole profession in the UK that make their coin by finding ambiguity, hidden meaning not intended and the ambiguity in the name of justice. Some may call them many names, I just stick to calling them the worst and most derogatory name I can think of…….the legal profession.
 

deema

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If you get a qualified electrician in then the job will be correct
Absolutely not the case. Like every profession there are good and honourable trades people and absolute idiots. The trade body IMO is extremely lacking.
 

Phil Pascoe

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^^^^ :LOL:

I bought my Victorian house 30 years ago. It was a mess, we had to move in quickly, so it was paint everything white. I found a loop of 2.5mm in a cupboard where someone was obviously intending to add a socket, so I told my wife I'd tidy it up before painting. I went to pull the fuse and found all the tails mixed up - the basement lights and the immersion heater were on one fuse, the rings on two seperate fuses ...

I checked them all out, put them back where they should have been and labelled everything. I went to the pub a few days later and a friend asked how I was getting on. He said there was one thing I shouldn't have any problem with - the electrics. I asked why. Because the guy you bought the house from is a qualified electrician, he said.
 

NetBlindPaul

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I think like most of the regs they can be open to interpretaion, but it is not just the enclosure needs to be non combustable because the actual term used is " to contain a fire" which also requires all cable entry / exit points are also sealed in order to comply which is what gives the most issues in undertaking.

A consumer unit is not required to be able to “contain a fire”, the IP rating requirements have not changed for many editions, & “contain a fire” is not the term used.
The clause in BS 7671 is 421.1.201.
Screenshot attached, I get the IET books electronically for the work I do with them.

6AB4D078-AD1D-4CAD-A92F-17452FA04672.jpeg
 
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