1983 Willesden College London, I passed my C&G as a young lad and oh boy if John Ward was the lecturer in those days I would have passed in 1 month and not sat day dreaming for 2 years. Excellent commentary with a bit of humour added. This should be used in Class Room now. Well done John.
Thanks, you have great detail in this video. I learnt a lot especially about the low protection of the supply cable at cut out making them very dangerous.
I hope John does a video on installing a second consumer unit ,say for example one that supplies armoured cable going to a shed used for welding. So when the dam housing association change the cu again (every 7 years currently) they don't mess with the shed power putting a MCB that's woefully underrated for the task ,while also taking everything they remove with them and for bonus points shortening all the wires.
Thanks for another great video, these are all fantastic videos and so much information and really well explained, thanks for taking the time out to help others who are new to the trade!!
I'm so glad that we have in Germany 3 Phase 63A comming in, in normal Homes. For the Stove 3 Phase 16A, and for the Tanklass water heater 32A 3P :). I never could live without 230/400V 3 Phase.
+Grumpy Electrician The same thing in Finland. I think that the kWh meter installation appeared in the video was quite a Chinese-looking. In Finland corresponding assembly looks like this: www.sahkonumerot.fi/3332078/img/large/color.jpg
"Arc and spark and kill people in the vicinity" HAHAHAHAH!!!! I am sorry but JW has got to have the funniest dry british humor I have EVER encountered in my life. And I am an engineer for the US side of a British company and deal with a lot of my coworkers from across the pond. JW takes the take, literally! :-D
I love how you highlight the reality of getting the wiring in these things tidy :-) Keeping them tidy is another thing altogether, I've tried in the past, and then it all goes horribly wrong whenever something needs changing, hahaha. I may well be in touch regarding a huge, ancient, but beautifully made and apparently working order moving magnet voltmeter btw, that I really want to make work somehow, apparently intended to connect across two phases, unless I'm misunderstanding something. With a coil resistance of 2.5k, it'd have about 96 milliamps running through it at 240v which seems a lot, double that at 480v across phases, so it's quite scary.
That wiring may be a bit messy, but at least the installer has left a good amount of length on the wires to allow for future modifications to the circuits, and minimised on sharp (e.g. 90 degree) bends. Much rather that than come to install a new C.U. and find the old wiring, though nicely laid-out for the old board, has been trimmed down too short for the replacement.
My (external) meter box has the useful extra of a single pole isolating switch on the live between the meter and the connectors for the consumer unit. That is very convenient (and ought to be standard) as it means that it's possible to replace the CU (or all its innards) without calling out the local power distribution company.
Hi thanks for vid info however for a learner it would be helpful to have 1:better light on the main in and its box . 2: a pointer to the items you speak about . Thanks again .
the inventor of RCD is a genius, i bet if the whole world apply RCD in homes then major life counts will be saved, i got electrocuted alot during my device repairs, i wish i had RCD(GFCI) back then
Our consumer unit is pretty much like this, apart from the cooker circuit hanging off the RCD, and also for some reason the MCBs are a different brand to the RCD and main switch, and also there is a separate smoke detector circuit which is not RCD protected I have been thinking about getting it replaced with an RCBO one (especially with what happened at the market weighton house, back when i still lived in market weighton, which nearly resulted in frozen food thawing due to an RCD tripping, only for it to turn out that the fault was on a completely different circuit)
Water bond must be within 300mm of point of isolation (stopcock) or at point of entry to property. Gas bond must be within 600mm of point of isolation (meter) or at point of entry to property. RCD test label on consumer unit? Mixed color warning label on consumer unit? Single insulated cables below 'Henley' connection blocks. I'm sure there's probably more but I want paying too much attention.
+CableWrestler There is a reasonably practicable ruling on water and gas bonds. RCD label looks to be on MCB cover (which was flipped down) Aside form the meter tails, all wires appeared to be brown, blue and green/yellow. If that's the case in the walls, then mixed colour warning not required. Also, JW didn't fit this consumer unit.
EC15 Earth clamp is a bit dubious on lead incoming service cable, inadvertently over-tightening this clamp could damage or short out the cable leading to a small explosion as this cable is likely backed up at the transformer location by a fuse of around 400 amps . Service provider should ideally sweat a lead plumb onto cable with a short earth lead onto a fixed earth terminal block to which the consumer unit main earthing conductor may be connected.
In the USA it's required that all panel boxes have wires perfectly installed and parallel. We have two or three phase power too. And we have a main disconnect. At 110 and 220volts, we may have on a house 60 to 400 amp service.
That CU will have the OCD crowd wincing. Quite a lot of exposed copper at the junctions and, do I see that a few of the strands on the neutral tail feed from the meter cupboard are cut off short and don't go into the main isolator switch terminal in the CU?
+Graham Langley Technically it's the consumer's property but only the board's (modern parlance 'DNO's) equipment is supposed to be fitted to it. But nobody pays any attention to that much. Our entire CU is on the backboard along with the meter/cutout.
Thanks been looking everywhere for a nice detailed videos I've always wanted to know what's behind the breakers! I just had all myn changed from fuses to CB and rcds wires ever where
11:01 earth point number 13, seems to be a rather dubious looking connection. Looks as if it could easily be disconnected; leaving that circuit with no earth continuity.
Hi, I noticed that in your clip your RCDs are marked Live and Neutral but I notice with both the Hager and MK RCDs that they have no markings on the twin pole I presume this is because they can go either way around to aid in the configuration of the unit as long as if you have the live supply on the top right that you have the live load on the bottom right side.
Thanks to John for uploading this great guide! I am NOT a qualified sparks, but I do find myself attempting repairs on my little flat, or at work where I jobrole as a "maintenance guy". So, I know this is gonna sound like a dumb question, but when John mentions "the mains switch, the red one" at 8:20 in the video, is this the one that needs to be pressed DOWN if you want to cut power to the whole property, please? Advice welcome! (Thanks in advance!)
@@jwflame : Thanks for quick reply, John! Safety is everything in the electrical world, I reckon. (I should learn how to test if wires are LIVE or not, really.. I've read somewhere you can do this with something as simple as a "Neon Tester Screwdriver" but I think the pros use digital multimeters with "probes").. More research needed as usual!
Looks fairly similar to my Wylex which is quite old. I wonder if you can explain something with my configuration: It says "These circuits NOT protected by RCD" and that is basically every MCB. To the left, it says "These circuits protected by RCD" and they are all blanked off. However, the main 100A switch (which I suspect was a later install) says RCD and has a test button on it. Does this mean that everything coming off that is RCD protected? Thanks
Appreciate this video is getting on a bit and slightly out of date, however, i just picked up the latest Toolstation flyer with some Contactum metal consumer units advertised as High Integrity 18th Edition dual split load (with a number of MCBs). States that it conforms with BS 7671 IET Amd 3, BS61439-3. However it has no AFDD or RCBOs for each circuit as I am more or less being drummed into. So does this mean then that we DO NOT actually have to fit RCBOs for each final circuit and omit AFDD and we are being told a red herring? Does anybody ACTUALLY know without having a guess at what they think it might be or is in their opinion?
61439-3 is the standard for consumer units, they will all comply with that. Amendment 3 refers to the 17th edition which was published in 2015 and has been obsolete for years, replaced by the 18th edition in 2018 and the 18th Amendment 2 in 2022. Amendment 2 can be used from March 2022 and is the only option from September 2022, so certain retailers of consumer units are discounting their old stock to get rid of it while they still can. In 2022, AFDDs are required for some circuits in some types of building, and recommended for most others. RCDs are required for pretty much every circuit in a domestic dwelling, and those RCDs must be type A or better unless it's the unusual situation of a circuit with only a fixed resistive load such as an immersion heater. Surge protection is required for almost all installations. Multiple circuits from a single RCD is a poor choice and has been for years, and although it's possible to fit such things and comply with BS7671 in a few cases, in most situations RCBOs are the only realistic option. The main items are division of installation where the failure of one circuit should not affect others and the maximum leakage current in normal use being a maximum of 9mA per RCD, which is very easily exceeded where you have 50% of a property attached to a single RCD. Other less common problems are that items such as PV inverters can't share an RCD with anything else, and some items of equipment require a specific type of RCD such as F or B. The consumer unit in the video is from the very end of the 16th edition era in 2007, and at the time RCDs were not required for circuits such as lighting, which is why it has a single RCD which only covers some of the circuits.
Why is the fuse and meter always placed onto a backboard when the consumer unit is not. Is it a requirement ? Also can you simply add another backboard for an isolator if there were not enough room on the first ?
John gives a good impression he has a fair amount of knowledge and whilst he may have not fitted the adjustable earth clamp to the DNO cable to provide a TN-S earthing system this means of connection is totally unacceptable. In fact the manufacturer for some of these clamps actually state they are not suitable for this purpose.
+John Ward hi pal, just a quick question you may be able to answer for me. I'm actually an electrician myself but you never stop learning. Why is it that meter tails can't enter in different holes due to possible eddy currents but in the actual meter, they all enter through speedster holes ? Thankyou
+TheAerobicmonkey ok let's see if you can understand this You are not allowed to put meter tails through separate holes In a consumer unit. But in the meter they all enter seperate Why ?
+TheAerobicmonkey ok let's see if you can understand this You are not allowed to put meter tails through separate holes In a consumer unit. But in the meter they all enter seperate Why ?
Hi JW, thank you for sharing your endless knowledge, very appreciated indeed. Can you please show me where that socket is taking it's live and neutral feeds?
would it be good practice to install a separate double pole isolating switch between the meter and CU so that you could isolate the CU when it comes time to replace / upgrade it ?
I was always taught to do as this shows, Cooker NOT RCD protected as (1) it's not a portable appliance so no need to have an RCD, and (2) the high leakage current especially from ovens can cause nuisance tripping. The usual socket on the cooker connection unit was never mentioned :)
+TheChipmunk2008 You need to get up to date on the regs then! For several years it has been necessary to RCD protect all circuits if the wiring is buried in walls and less than 50mm from the surface. For most houses this means all circuits so cookers,and lights are now protected by a 3omA RCD.
+Taylortwocities Real? I had my oven hooked up to a 30mA RCD and all it did was exactly what TheChipmunk said it would do... nuisance trip! How you supposed to get around that then?
+Gavzach - At what voltage though? Isn't it 120V over there? So, 120V @ 200A, versus 240V at 100A are the same, right? Regarding the number of circuits, a fairly usual amount would be around 10 circuits here for a typical domestic installation here. Something like: Downstairs Sockets (32A) Kitchen Sockets (32A) Upstairs Sockets (32A) Downstairs Lighting (6A) Upstairs Lighting (6A) Cooker (40A) Shower (50A) Immersion Water Heater (16A) Heating Control (6A) Alarm System (6A)
+Gavzach Everything is 240V here, homes in Britain do not normally have air conditioning and water & space heating is usually gas or oil. Where electricity is used for space heating, a separate board would usually be provided for that.
+9ff70f96 Canada is the same basically as the U.S and a common residential service size is 100A 120/240V 1 phase but just as common is 200A 120/240V 1 phase for larger homes. There is the odd "125A" service and even availible for extremely larger houses , (and they are rare, but I have seen one!) a 400A service can be installed. Panels for service entrance vary from a minimum usually of 24 spaces all the way up to a whopping 84 spaces depending on the amperage rating of the panel.... Meters are located outside generally, and the main breaker is located within a separate compartment within the panel, a "Combination service entrance panel".
+9ff70f96 most of our receptacles are 15 amp and are usually shared with the lighting circuits in the room. we have the 50 amp 240 volt range receptacle 2 20 amp receptacle circuits a 20 amp receptacle for the fridge 20 amp circuit for the dish washer heaters are usually 240v at 20 amp. 20 amp circuit for the washing machine 30 amp 240 volt for the dryer 240 20 amp circuit for the water pump 30 amp circuit for the water heater 15 amp circuit for the door bell 20 amp circuit for bathroom receptacles 15 amp for the lighting in the bathroom and what ever other circuits the owner wants to have out door receptacles outdoor lights sub panel for the shed. etcetera
i still have a cast iron cutout fuse. all the electricians refuse to work on our house until it is replaced but the people who need to replace it wont because they arent qualified to do so aparently.
John just curious how do you take the live and neutral from the meter to the consumer. Like how do you work with the live..how do you isolate it in order to connect it to the consumer unit..
Electricians are meant to contact the local power distribution company and have them pop the main fuse out (which has a seal). However, it's not unknown for some electricians to just do it themselves. My house has an isolator after the meter, so that's unnecessary. Why that isn't mandated as a standard I don't know. A lot of this probably goes back to the days when power supply was a state monopoly without the clear demarcation points.
Hello this is Troy I would like you to tell me how I can connect solar panels up to my mains electric in the same type of box that you had on your video and is it quite simple many thanks Troy
I have always been wondering why on the islands the amount of fuses is so little, for the same (house) space we often have two or three times as much fuses around here. But then again people on the islands are probably wondering what those on the mainlands need all their fuses for...
Well here we get to the only real advantage of the 32 A ring mains: you only need half as many breakers as with 16 A radial circuits. In the US you've got even more breakers because a US 15 A circuit can only carry half the load of a European 16 A circuit (half the voltage, same current).
Ragnar8504 It also seems that the amount of circuits is sometimes bigger here. I currently live in a house that has two breakers for almost every room, one for the lights and one for the sockets. One breaker for each floor, one gfci for each floor. Two levels of breakers for all mains together (one per phase) and one three phase master switch. Plus a few extra circuits like three phase oven, one each for washing machine, dryer and dishwasher. And the outside has its own fuse and gfci. And I have 4 breaker panels, one per floor and one main panel.
Braid and a constant force spring, example here: www.cablejoints.co.uk/sub-product-details/3m-scotch-electrical-tapes/constant-force-springs they maintain proper contact without any danger of over tightening and damaging the cable.
Never understood why in the UK you don't have a switch on the breaker itself, what do you do if you have to change the main switch or the cable that goes from the meter to the main breaker ? Also having a main fuse, if you burn that what you do ? Better to have a breaker integrated in the meter, and that is also a minimum protection for people that simply connect all the home wiring directly in the meter with no breakers or RCD (yes, I've seen it)
For changing the consumer unit or meter, the supplier fuse is removed - that's what it's designed for. If that fuse fails (which is almost never), the supplier will replace it.
John , i have a similar unit to this my electrician suggests i need a new compliant consumer unit as he is wiring a kitchen extension to my house and the unit needs to be compliant so a certificate can be issued for the works .any views , the board will still be compliant but will any new works be ?effectively the same white goods will be run with an additional dozen down lights dotted around . He claims a new unit would be circa £500 ..for the unit !maybe fitted would be correct? Great video .
All of them as described in this video: th-cam.com/video/Sc0tJGl4Oas/w-d-xo.html Normally these are done before installing a replacement consumer unit, so that any faults can be fixed first.
Thanks for your quick replay. I love your videos. They are very easy to understand, instructive and at the same time in depth but not too complicated. Keep at it helped even my wife to understand electrics to some degree. Thanks, again
John, We had a annual gas safety check (landlord pays for this) on our supply and the gas engineer failed our gas meter as it is too close to the electrics (all in the same cupboard about 0.75 metres apart) can we force our landlord to get one or other supply moved as they are refusing saying it is "Only an advisory" But the gas engineer stated on the paper work "Gas supply too close to electricity supply and it is deemed as DANGEROUS" Would like your thoughts as an Electrician please. Thanks Clive
+Clive Clarke-Watson Minimum separation distance is 150mm, between consumer unit & gas meter/pipework, or 25mm between gas pipes and cables, switches etc. If yours is 750mm, this is significantly greater than the minimum required and therefore not a problem. Even if the distance was less than 150mm, an alternative is to install an insulating panel between the gas and electric items. Certainly not dangerous.
Hi there John, do your consumer units in the UK use an M.E.N. system where the earth and neutral are bonded inside the switchboard and then the earth bonded to water pipes and an earth stake outside the house?
Hi John have watched a few of your videos and they very informative. I have some basic knowledge and would like to increase this. I know how most wiring is done but as not qualified can't do it. But my question is why have I seen videos where probes are placed in all the outlet holes. Many thanx
Hi I from the Chicago area and was just watching to learn, boy do we do things different here ! No incoming power would ever be in a wooden box or even set up like that the meter is usually outside and is sealed also acts as a disconnect on a home . Our panels are much bigger new standards call for arc fault on all circuits in England is it usual to have only 1 hot and neutral or 120volt only I though it was all 220 volt and is it 220 one one line w neutral or 220 on two phases, Here we have 3 wire service two 120volt lines that share an unfused neutral so from line to line 220 volt line to neutral 120 volt all services have a main breaker with two sources of ground one rod at the meter and one at the incoming water line before the shut off valve if on a well then a second rod at least 6feet away from esch other.
And we in the Netherlands have also neutral connectors on the breakerunits,so the neutral is also disconnected when a shortcircuit.So no common bar for the neutral wires.And indeed a hot phase and neutral,no two 120 volt lines!!
Hi john, great vids, have learnt a lot. Just wondered if you could do a video regarding a sub main, how to wire it when you have no spare mcb etc. Cheers, keep up the good work.
What? 100 Amps? Here in Italy we have MCBs on the meter itself and you have to pay more to even get 4,5 kW, on normal plans you just get 3 kW and you can’t even run a dishwasher and a washing machine at the same time!
Hi JW. If the cables enter the consumer unit from the bottom (there are knock out ports top and bottom so i assume its not too unusual), whats best practice for neat wiring? I'm considering running the cables up behind the MCB bar (where they clip in). Would there be any issue with that, or is this an acceptable way to run the cables? Thanks
Yes, behind the bar is the usual method, ideally using holes in the enclosure which are in line with the MCB or other device to avoid cables crossing over inside the consumer unit. If holes in the top are used, they must be sealed to at least IP4X, a common method of achieving that is to fix a length of 50mm x 50mm plastic trunking across the top of the consumer unit to contain the cables.
+John Ward that's great thanks. I've been looking into grommets etc for the knock outs, but can't find much! From your reply noting the use of the top holes, I assume I don't need them if using the knock outs on the bottom?
Grommets are still required to prevent the cables being damaged by the sharp metal edges of the consumer unit. Search for "open pvc grommet" for the usual style, or "stuffing gland" for those with better sealing.
No. Lighting circuits require RCD protection, as do virtually all other circuits. If it's tripping the RCD there is a fault which must be found and repaired.
@@jwflame as a quick fix couldn't u just put on unprotected section use neutral bar b4 rcd side ie say just to get lights on for night changing skeleton 2moźz 18 ways all the lighting not on a rcd and it's a mess
Hi John, have you ever heard of anyone actually getting into trouble for unauthorised pulling of the main fuse? I know some electricians can be quite cavalier about the whole thing. Is it just an empty threat?
if i turn off the large rcd ie the ones with the thick wire coming from the supply in . does that mean that the buzz bar is dead. i want to put a ring main into the shed and i have a spare 30a fuse unit and i am confident that im doing it correctly i just want to make sure when working with mains power
In most cases yes - after that it's usual to go to 3 phase 100A, and above that it's higher current ratings but still with 3 phase. However higher capacity single phase can exist, really depends on the electricity network in the local area, what capacity is available, etc.
Hmm, I would be more concerned about the exposed single core insulation, just below the single pole junction boxes, than about perfectly neat cable routing.
Just looking at this older vid John and ... I have a question pleeze ? Should the total MCB's current rating (all MCB's added up) never exceed the main fuse or does diversity apply ? I heard this somewhere... 🤔 😎👍☘️
For domestic use, diversity applies. The rating of the main switch should however be equal to or exceed (1) the supply capacity (the fuse in the cut-out) and (2) the maximum expected load current. For industrial use, it may not always be appropriate to apply diversity, as in a factory all equipment may be in continuous use during the day/shift.
Keep up the excellent videos.. very well presented.. and informative.. have a question for domestic installer.. what type of tester you recommend.. kewtech or fluke.. and model..
I have only used Fluke (previously Robin), so can't recommend or comment on other makes. However other than being able to do the tests required, the main consideration should be that is is designed/built to withstand incorrect use or faults without bursting into flames or exploding.
@John Ward Really? In North America the ground and neutral wires are all connected to the same bar, which is then connected to the main neutral supply coming into the panel. It it also grounded via either the water supply pipe or a metal rod planted outside near the foundation. You should do a video explaining (or reacting to) how North American power works.
I want to have an Electrician run a separate power supply for my stereo equipment. I have been advised that I need a 30 amp supply. Could I run 4 separate cables from the consumer unit so each hi-fi separate has it's own dedicated supply. Is it worth running a separate earth 6mm from the consumer unit to the four outlets that I have in mind.
You could have separate cables for each item, although electrically it won't make any difference. A separate earth is not required, the earth in the power cable(s) will be adequate, and the earth would only carry current in the event of a fault.
John Ward Thanks for the reply John. I have a couple of issues with the electrics. Firstly when we have been away for a weekend break,on our return we find the whole house has been without power, so I have to push the main power switch to once again have power supply from consumer unit. Secondly I have a couple of power amps, these or one of them seems to make a buzzing noise around 6 am every morning or when my partner turns on the hair drier. Am I right thinking that the amps have dc in the ac supply? Interference on the line. Great informative videos by the way.
The whole house tripping is probably an RCD (with test button on it), in which case it's a fault somewhere either with the wiring or an appliance. Water leaking is a common one, such as outside lights, wiring to garages/sheds, boilers, water heaters and similar. The buzzing will be interference either through the mains wiring or being picked up by signal cables, speaker cables etc. The hair dryer should have interference suppression in it but that may have failed. For the 6am one, it is probably something switching on at that time such as a heating system - not necessarily in your house either.
Thank you for replying JW. I know have watched quite a few of your videos & enquired with a training centre about now doing the 17th edition plus another course. I expect it's quite an up hill learning curve, but would help me regarding carrying out electrical works. Can you recommend any up-to-date -books to learn from.
mate i wish u could do a video on how to add a 30amp wire and add a new breaker switch i got a koi pond and need to add a heater but all the decent heaters are 30amp or more so i need to add it i got room on my unit for another 2 switches but not sure how to i got a better understanding after watching this but not 100% accually i just looked again and there is the 2 breaker switches there but theres nothing wrote underneath and they turn off would i be able to run a 30amp electric cable to it it says that it is 63amp max i thinking is the swiches got power running to them so i would have to connect the wire to the switch then would be running is that write thanks
I want to split the consumer unit, so that one half is using the incoming grid supply, and the other half from a battery bank, which is charged by a solar aray. Is this consider good practise? or do I need two consumer units!
If you change supplier, the new supplier normally takes over the old meter from the old supplier. If you are unfortunate enough to have a smart meter installed, this often means that the smart meter is no longer smart once you move to the new supplier and has to be read just like an old non-smart one.
Generally, the new supplier is not at all bothered about the meter. They just want to take a reading so they can start charging you and so that your previous suppler can present you with a final bill. The same thing happens when you buy a house. I have done both and neither time was the meter changed. In fact, it’s still a traditional electromechanical type. At the moment in (most of) the U.K., you can request a so called ‘smart’ meter. The supply company will then fit one free of charge.
+codemsan - A number of them will be ring-type circuits that have two legs going out in different directions around the installation but forming a ring or loop-style circuit that typically hosts a good number of socket outlets. So like: DB --- SOCKET --- SOCKET --- SOCKET --- SOCKET --- SOCKET --- DB, where DB = a single MCB over-current protection device in the DB for that particular circuit (commonly rated at 32A). Each leg on a "socket ring/ring main/final circuit" is typically 2.5mm2 copper rated to handle in region of 23A (subject to derating rules due to layout, e.g. in walls, through insulation, clipped direct, on cable trays, etc), but with it being wired in a loop fashion to form a ring, presents a circuit capable of almost twice that (e.g. in the region of 40A or more). It's basically a radial circuit with a leg back from the last socket outlet back to the source.
+codemsan The ones in the video are rings, however it is permitted to have 2 or more wires in a single circuit breaker even if not a ring. Usually happens when circuits are rearranged to make space for a new one, e.g. put 2 lighting circuits onto a single breaker so a larger capacity breaker can the be installed.
how to complately off the off the electricity to work on home wire repair when i off it indicater light still works what it means it is not completely how to completely off it
Comments on taking time on make inside consumer unit tidy which is just a everyday thing for a descent sparky but you have now probably take an age explaining this
I am no electrician but im trying to save a few hundred pounds. I have the same mains consumer unit. I want to run some power from my house to my shed which is around 30mtrs from my house. Can i run a small mcb consumer next to mains consumer with a isolated switch before drill out.and then run 16awg armoured to shed. Cant find nothing online to simplify this procedure
+Allen Goldsmith Daniel is right. Of course, the very first step is to apply to your electricity supplier for them to provide an E7 facility. Then you'll need a registered electrician to suuply the necessary distribution gear and connect it up.
1983 Willesden College London, I passed my C&G as a young lad and oh boy if John Ward was the lecturer in those days I would have passed in 1 month and not sat day dreaming for 2 years. Excellent commentary with a bit of humour added. This should be used in Class Room now. Well done John.
Terrific presentation style, informative & to the point with a dash of humour, top marks, ten out of ten.
I love the no nonsense deadpan presentation style.
I like the way you pre-emptively answer the questions that arise as I watch !
Thanks, you have great detail in this video. I learnt a lot especially about the low protection of the supply cable at cut out making them very dangerous.
I hope John does a video on installing a second consumer unit ,say for example one that supplies armoured cable going to a shed used for welding.
So when the dam housing association change the cu again (every 7 years currently) they don't mess with the shed power putting a MCB that's woefully underrated for the task ,while also taking everything they remove with them and for bonus points shortening all the wires.
Best on TH-cam explaining!!!!! Thank you very much for sharing your knowledge!!! Many Great video!!!
Thanks for another great video, these are all fantastic videos and so much information and really well explained, thanks for taking the time out to help others who are new to the trade!!
I'm so glad that we have in Germany 3 Phase 63A comming in, in normal Homes. For the Stove 3 Phase 16A, and for the Tanklass water heater 32A 3P :). I never could live without 230/400V 3 Phase.
+Grumpy Electrician The same thing in Finland. I think that the kWh meter installation appeared in the video was quite a Chinese-looking. In Finland corresponding assembly looks like this: www.sahkonumerot.fi/3332078/img/large/color.jpg
Same in sweden 3phase
+peto22 It probably got harmonized through some EN(what ever)
+Grumpy Electrician Obviously not, as UK would have to do it. Even new domestic properties are single phase.
+Grumpy Electrician single phase 240v 200amp FTW
"Arc and spark and kill people in the vicinity" HAHAHAHAH!!!! I am sorry but JW has got to have the funniest dry british humor I have EVER encountered in my life. And I am an engineer for the US side of a British company and deal with a lot of my coworkers from across the pond. JW takes the take, literally! :-D
I love how you highlight the reality of getting the wiring in these things tidy :-) Keeping them tidy is another thing altogether, I've tried in the past, and then it all goes horribly wrong whenever something needs changing, hahaha.
I may well be in touch regarding a huge, ancient, but beautifully made and apparently working order moving magnet voltmeter btw, that I really want to make work somehow, apparently intended to connect across two phases, unless I'm misunderstanding something. With a coil resistance of 2.5k, it'd have about 96 milliamps running through it at 240v which seems a lot, double that at 480v across phases, so it's quite scary.
Great videos John, it's really helping my learning as a new electrician, please keep up the good work!!!
That wiring may be a bit messy, but at least the installer has left a good amount of length on the wires to allow for future modifications to the circuits, and minimised on sharp (e.g. 90 degree) bends. Much rather that than come to install a new C.U. and find the old wiring, though nicely laid-out for the old board, has been trimmed down too short for the replacement.
Thank-you for taking the time to do these videos, they are a great help.
My (external) meter box has the useful extra of a single pole isolating switch on the live between the meter and the connectors for the consumer unit. That is very convenient (and ought to be standard) as it means that it's possible to replace the CU (or all its innards) without calling out the local power distribution company.
Great Explanation and so well spoken.
Thanks John, really great simple walk through.
Glad i found your channel john, it is very informative.
This guy is great
Hi thanks for vid info however for a learner it would be helpful to have 1:better light on the main in and its box .
2: a pointer to the items you speak about .
Thanks again .
the inventor of RCD is a genius, i bet if the whole world apply RCD in homes then major life counts will be saved, i got electrocuted alot during my device repairs, i wish i had RCD(GFCI) back then
Our consumer unit is pretty much like this, apart from the cooker circuit hanging off the RCD, and also for some reason the MCBs are a different brand to the RCD and main switch, and also there is a separate smoke detector circuit which is not RCD protected
I have been thinking about getting it replaced with an RCBO one (especially with what happened at the market weighton house, back when i still lived in market weighton, which nearly resulted in frozen food thawing due to an RCD tripping, only for it to turn out that the fault was on a completely different circuit)
I'm just about to fit a new cu in my workshop... This vid was very useful ... Thank you John...
Water bond must be within 300mm of point of isolation (stopcock) or at point of entry to property.
Gas bond must be within 600mm of point of isolation (meter) or at point of entry to property.
RCD test label on consumer unit?
Mixed color warning label on consumer unit?
Single insulated cables below 'Henley' connection blocks.
I'm sure there's probably more but I want paying too much attention.
+CableWrestler There is a reasonably practicable ruling on water and gas bonds.
RCD label looks to be on MCB cover (which was flipped down)
Aside form the meter tails, all wires appeared to be brown, blue and green/yellow. If that's the case in the walls, then mixed colour warning not required.
Also, JW didn't fit this consumer unit.
EC15 Earth clamp is a bit dubious on lead incoming service cable, inadvertently over-tightening this clamp could damage or short out the cable leading to a small explosion as this cable is likely backed up at the transformer location by a fuse of around 400 amps . Service provider should ideally sweat a lead plumb onto cable with a short earth lead onto a fixed earth terminal block to which the consumer unit main earthing conductor may be connected.
+Arfur Watt Or convert system to TN-C-S.
Thanks for sharing the knowledge, JW.
Very useful video John
Thanks
In the USA it's required that all panel boxes have wires perfectly installed and parallel. We have two or three phase power too. And we have a main disconnect. At 110 and 220volts, we may have on a house 60 to 400 amp service.
That CU will have the OCD crowd wincing. Quite a lot of exposed copper at the junctions and, do I see that a few of the strands on the neutral tail feed from the meter cupboard are cut off short and don't go into the main isolator switch terminal in the CU?
I've watched this video twice now, Two different days and I've nodded off both times
Best teacher
Doesn't the meter board also belong to the DNO so you're not supposed to fix anything to it, such as the double socket and bell transformer as here?
+Graham Langley Technically it's the consumer's property but only the board's (modern parlance 'DNO's) equipment is supposed to be fitted to it. But nobody pays any attention to that much. Our entire CU is on the backboard along with the meter/cutout.
The board either belongs to the dno or supplier, not the customer. The customer shouldn't install anything on it but it's ignored nationwide
So that's two completely opposing answers. Anyone care to add an authoritative answer with actual evidence?
Thanks been looking everywhere for a nice detailed videos I've always wanted to know what's behind the breakers! I just had all myn changed from fuses to CB and rcds wires ever where
11:01 earth point number 13, seems to be a rather dubious looking connection. Looks as if it could easily be disconnected; leaving that circuit with no earth continuity.
Hi, I noticed that in your clip your RCDs are marked Live and Neutral but I notice with both the Hager and MK RCDs that they have no markings on the twin pole I presume this is because they can go either way around to aid in the configuration of the unit as long as if you have the live supply on the top right that you have the live load on the bottom right side.
Thanks to John for uploading this great guide! I am NOT a qualified sparks, but I do find myself attempting repairs on my little flat, or at work where I jobrole as a "maintenance guy". So, I know this is gonna sound like a dumb question, but when John mentions "the mains switch, the red one" at 8:20 in the video, is this the one that needs to be pressed DOWN if you want to cut power to the whole property, please? Advice welcome! (Thanks in advance!)
Yes, that's the one.
@@jwflame : Thanks for quick reply, John! Safety is everything in the electrical world, I reckon. (I should learn how to test if wires are LIVE or not, really.. I've read somewhere you can do this with something as simple as a "Neon Tester Screwdriver" but I think the pros use digital multimeters with "probes").. More research needed as usual!
writerNB - Yes use proper test equipment, never, ever rely on a neon screwdriver.
Looks fairly similar to my Wylex which is quite old. I wonder if you can explain something with my configuration: It says "These circuits NOT protected by RCD" and that is basically every MCB. To the left, it says "These circuits protected by RCD" and they are all blanked off. However, the main 100A switch (which I suspect was a later install) says RCD and has a test button on it. Does this mean that everything coming off that is RCD protected?
Thanks
Seems to be so, but you shouldn't just assume with electrics. To be certain you would need to have a look inside the consumer unit.
I presume the socket mounted beside the fuse board was wired directly into the MCB for the downstairs sockets?
Appreciate this video is getting on a bit and slightly out of date, however, i just picked up the latest Toolstation flyer with some Contactum metal consumer units advertised as High Integrity 18th Edition dual split load (with a number of MCBs). States that it conforms with BS 7671 IET Amd 3, BS61439-3.
However it has no AFDD or RCBOs for each circuit as I am more or less being drummed into. So does this mean then that we DO NOT actually have to fit RCBOs for each final circuit and omit AFDD and we are being told a red herring? Does anybody ACTUALLY know without having a guess at what they think it might be or is in their opinion?
61439-3 is the standard for consumer units, they will all comply with that.
Amendment 3 refers to the 17th edition which was published in 2015 and has been obsolete for years, replaced by the 18th edition in 2018 and the 18th Amendment 2 in 2022.
Amendment 2 can be used from March 2022 and is the only option from September 2022, so certain retailers of consumer units are discounting their old stock to get rid of it while they still can.
In 2022, AFDDs are required for some circuits in some types of building, and recommended for most others.
RCDs are required for pretty much every circuit in a domestic dwelling, and those RCDs must be type A or better unless it's the unusual situation of a circuit with only a fixed resistive load such as an immersion heater.
Surge protection is required for almost all installations.
Multiple circuits from a single RCD is a poor choice and has been for years, and although it's possible to fit such things and comply with BS7671 in a few cases, in most situations RCBOs are the only realistic option.
The main items are division of installation where the failure of one circuit should not affect others and the maximum leakage current in normal use being a maximum of 9mA per RCD, which is very easily exceeded where you have 50% of a property attached to a single RCD. Other less common problems are that items such as PV inverters can't share an RCD with anything else, and some items of equipment require a specific type of RCD such as F or B.
The consumer unit in the video is from the very end of the 16th edition era in 2007, and at the time RCDs were not required for circuits such as lighting, which is why it has a single RCD which only covers some of the circuits.
Why is the fuse and meter always placed onto a backboard when the consumer unit is not. Is it a requirement ? Also can you simply add another backboard for an isolator if there were not enough room on the first ?
great video john very helpful
John gives a good impression he has a fair amount of knowledge and whilst he may have not fitted the adjustable earth clamp to the DNO cable to provide a TN-S earthing system this means of connection is totally unacceptable. In fact the manufacturer for some of these clamps actually state they are not suitable for this purpose.
Peter Ward - You must be his Dad - Leave John Ward alone he is doing a great job. "The Ward Family" lol
what is the item plugged into the dual sockets in the cupboard?
+jusb1066 Transformer for the doorbell.
+John Ward hi pal, just a quick question you may be able to answer for me. I'm actually an electrician myself but you never stop learning.
Why is it that meter tails can't enter in different holes due to possible eddy currents but in the actual meter, they all enter through speedster holes ?
Thankyou
+Sean Mac separate.... Not speedster(auto correct)
+TheAerobicmonkey ok let's see if you can understand this
You are not allowed to put meter tails through separate holes In a consumer unit.
But in the meter they all enter seperate
Why ?
+TheAerobicmonkey ok let's see if you can understand this
You are not allowed to put meter tails through separate holes In a consumer unit.
But in the meter they all enter seperate
Why ?
Thank you Mr Ward
Hi JW, thank you for sharing your endless knowledge, very appreciated indeed. Can you please show me where that socket is taking it's live and neutral feeds?
Is that even reinforced insulation on the incoming wires?
I'm kinda glad they force us to buy something a bit more substantial....
+stefantrethan Normal PVC insulation (red / black) with a grey PVC covering over it.
would it be good practice to install a separate double pole isolating switch between the meter and CU so that you could isolate the CU when it comes time to replace / upgrade it ?
No. Consumer units are replaced every few decades, by the time it's needing replacement, the separate isolator will need replacement as well.
The double socket and transformer should not be on the DNO's meter board.
I was always taught to do as this shows, Cooker NOT RCD protected as (1) it's not a portable appliance so no need to have an RCD, and (2) the high leakage current especially from ovens can cause nuisance tripping.
The usual socket on the cooker connection unit was never mentioned :)
+TheChipmunk2008 You need to get up to date on the regs then! For several years it has been necessary to RCD protect all circuits if the wiring is buried in walls and less than 50mm from the surface. For most houses this means all circuits so cookers,and lights are now protected by a 3omA RCD.
+Taylortwocities Real? I had my oven hooked up to a 30mA RCD and all it did was exactly what TheChipmunk said it would do... nuisance trip! How you supposed to get around that then?
+SeriousSchitt If an oven trips the RCD, it is faulty and should be replaced or or repaired.
Mica insulation in the heating elements often breaks down over time causing nuisance tripping. Cheap to replace.
your load centers in UK are small in America there is usually 200 amp service and at least 30 circuit breakers.
+Gavzach - At what voltage though? Isn't it 120V over there? So, 120V @ 200A, versus 240V at 100A are the same, right?
Regarding the number of circuits, a fairly usual amount would be around 10 circuits here for a typical domestic installation here. Something like:
Downstairs Sockets (32A)
Kitchen Sockets (32A)
Upstairs Sockets (32A)
Downstairs Lighting (6A)
Upstairs Lighting (6A)
Cooker (40A)
Shower (50A)
Immersion Water Heater (16A)
Heating Control (6A)
Alarm System (6A)
+Gavzach Everything is 240V here, homes in Britain do not normally have air conditioning and water & space heating is usually gas or oil.
Where electricity is used for space heating, a separate board would usually be provided for that.
+9ff70f96 yes it is 120 and you are correct with saying 120 at 200 amps is the same as 240 at 100 amps
+9ff70f96 Canada is the same basically as the U.S and a common residential service size is 100A 120/240V 1 phase but just as common is 200A 120/240V 1 phase for larger homes. There is the odd "125A" service and even availible for extremely larger houses , (and they are rare, but I have seen one!) a 400A service can be installed. Panels for service entrance vary from a minimum usually of 24 spaces all the way up to a whopping 84 spaces depending on the amperage rating of the panel.... Meters are located outside generally, and the main breaker is located within a separate compartment within the panel, a "Combination service entrance panel".
+9ff70f96 most of our receptacles are 15 amp and are usually shared with the lighting circuits in the room. we have the
50 amp 240 volt range receptacle
2 20 amp receptacle circuits
a 20 amp receptacle for the fridge
20 amp circuit for the dish washer
heaters are usually 240v at 20 amp.
20 amp circuit for the washing machine
30 amp 240 volt for the dryer
240 20 amp circuit for the water pump
30 amp circuit for the water heater
15 amp circuit for the door bell
20 amp circuit for bathroom receptacles
15 amp for the lighting in the bathroom
and what ever other circuits the owner wants to have out door receptacles outdoor lights sub panel for the shed. etcetera
i still have a cast iron cutout fuse. all the electricians refuse to work on our house until it is replaced but the people who need to replace it wont because they arent qualified to do so aparently.
John just curious how do you take the live and neutral from the meter to the consumer. Like how do you work with the live..how do you isolate it in order to connect it to the consumer unit..
Electricians are meant to contact the local power distribution company and have them pop the main fuse out (which has a seal). However, it's not unknown for some electricians to just do it themselves. My house has an isolator after the meter, so that's unnecessary. Why that isn't mandated as a standard I don't know.
A lot of this probably goes back to the days when power supply was a state monopoly without the clear demarcation points.
Hello this is Troy I would like you to tell me how I can connect solar panels up to my mains electric in the same type of box that you had on your video and is it quite simple many thanks Troy
Yes it's very simple. Just order the job from a professional and pay for it.
I have always been wondering why on the islands the amount of fuses is so little, for the same (house) space we often have two or three times as much fuses around here. But then again people on the islands are probably wondering what those on the mainlands need all their fuses for...
Well here we get to the only real advantage of the 32 A ring mains: you only need half as many breakers as with 16 A radial circuits.
In the US you've got even more breakers because a US 15 A circuit can only carry half the load of a European 16 A circuit (half the voltage, same current).
Ragnar8504 It also seems that the amount of circuits is sometimes bigger here. I currently live in a house that has two breakers for almost every room, one for the lights and one for the sockets. One breaker for each floor, one gfci for each floor. Two levels of breakers for all mains together (one per phase) and one three phase master switch. Plus a few extra circuits like three phase oven, one each for washing machine, dryer and dishwasher. And the outside has its own fuse and gfci. And I have 4 breaker panels, one per floor and one main panel.
What is the correct bonding connector that should be used for the bonding onto the lead sheathing.
Braid and a constant force spring, example here: www.cablejoints.co.uk/sub-product-details/3m-scotch-electrical-tapes/constant-force-springs
they maintain proper contact without any danger of over tightening and damaging the cable.
Never understood why in the UK you don't have a switch on the breaker itself, what do you do if you have to change the main switch or the cable that goes from the meter to the main breaker ? Also having a main fuse, if you burn that what you do ? Better to have a breaker integrated in the meter, and that is also a minimum protection for people that simply connect all the home wiring directly in the meter with no breakers or RCD (yes, I've seen it)
For changing the consumer unit or meter, the supplier fuse is removed - that's what it's designed for.
If that fuse fails (which is almost never), the supplier will replace it.
Also john i would like to ask you is it safe to fit mcb in nuetral and phase for non polorized supply eg euro
Only if it's a 2 pole MCB, where both neutral and phase are disconnected at the same time.
John , i have a similar unit to this my electrician suggests i need a new compliant consumer unit as he is wiring a kitchen extension to my house and the unit needs to be compliant so a certificate can be issued for the works .any views , the board will still be compliant but will any new works be ?effectively the same white goods will be run with an additional dozen down lights dotted around . He claims a new unit would be circa £500 ..for the unit !maybe fitted would be correct?
Great video .
HI JW. Question : once you replaced a consumer unit what kind of tests you have to do? Thanks
All of them as described in this video: th-cam.com/video/Sc0tJGl4Oas/w-d-xo.html
Normally these are done before installing a replacement consumer unit, so that any faults can be fixed first.
Thanks for your quick replay. I love your videos. They are
very easy to understand, instructive and at the same time in depth but not too complicated.
Keep at it helped even my wife to understand electrics to some degree. Thanks, again
John, We had a annual gas safety check (landlord pays for this) on our supply and the gas engineer failed our gas meter as it is too close to the electrics (all in the same cupboard about 0.75 metres apart) can we force our landlord to get one or other supply moved as they are refusing saying it is "Only an advisory" But the gas engineer stated on the paper work "Gas supply too close to electricity supply and it is deemed as DANGEROUS" Would like your thoughts as an Electrician please. Thanks Clive
+Clive Clarke-Watson Minimum separation distance is 150mm, between consumer unit & gas meter/pipework, or 25mm between gas pipes and cables, switches etc. If yours is 750mm, this is significantly greater than the minimum required and therefore not a problem.
Even if the distance was less than 150mm, an alternative is to install an insulating panel between the gas and electric items.
Certainly not dangerous.
*****
Thanks for that informative answer John! Keep the informative videos coming thanks Clive
that neutral wire tail is a fire waiting to happen.
Hi there John, do your consumer units in the UK use an M.E.N. system where the earth and neutral are bonded inside the switchboard and then the earth bonded to water pipes and an earth stake outside the house?
+australianstig Not in houses. It is used in some industrial installations.
In Australia the MEN system is used everywhere from households to commercial factories and office towers
John - At 8:31 you say "RCCD / RCD same name for different devices. I expect you meant different names for the same device.
God bless you man
Hi John have watched a few of your videos and they very informative. I have some basic knowledge and would like to increase this. I know how most wiring is done but as not qualified can't do it. But my question is why have I seen videos where probes are placed in all the outlet holes. Many thanx
If you mean 3 test probes, then some test equipment uses all 3 for some tests, such as RCD testing.
John Ward sorry I mis worded that. I meant first they do live and neutral then live and earth etc
Hi I from the Chicago area and was just watching to learn, boy do we do things different here ! No incoming power would ever be in a wooden box or even set up like that the meter is usually outside and is sealed also acts as a disconnect on a home . Our panels are much bigger new standards call for arc fault on all circuits in England is it usual to have only 1 hot and neutral or 120volt only I though it was all 220 volt and is it 220 one one line w neutral or 220 on two phases, Here we have 3 wire service two 120volt lines that share an unfused neutral so from line to line 220 volt line to neutral 120 volt all services have a main breaker with two sources of ground one rod at the meter and one at the incoming water line before the shut off valve if on a well then a second rod at least 6feet away from esch other.
One hot at 240V, one neutral. All appliances are 240V.
And we in the Netherlands have also neutral connectors on the breakerunits,so the neutral is also disconnected when a shortcircuit.So no common bar for the neutral wires.And indeed a hot phase and neutral,no two 120 volt lines!!
could you give me the name of that old black plastic box where the main fuse sits. I need new cover
Cutout, although in the UK it's the property of the electricity distributor, so if damaged call them on 105 and they will replace it.
@@jwflame thank you.
Hi john, great vids, have learnt a lot. Just wondered if you could do a video regarding a sub main, how to wire it when you have no spare mcb etc. Cheers, keep up the good work.
What? 100 Amps? Here in Italy we have MCBs on the meter itself and you have to pay more to even get 4,5 kW, on normal plans you just get 3 kW and you can’t even run a dishwasher and a washing machine at the same time!
Hi JW. If the cables enter the consumer unit from the bottom (there are knock out ports top and bottom so i assume its not too unusual), whats best practice for neat wiring? I'm considering running the cables up behind the MCB bar (where they clip in). Would there be any issue with that, or is this an acceptable way to run the cables? Thanks
Yes, behind the bar is the usual method, ideally using holes in the enclosure which are in line with the MCB or other device to avoid cables crossing over inside the consumer unit.
If holes in the top are used, they must be sealed to at least IP4X, a common method of achieving that is to fix a length of 50mm x 50mm plastic trunking across the top of the consumer unit to contain the cables.
+John Ward that's great thanks. I've been looking into grommets etc for the knock outs, but can't find much! From your reply noting the use of the top holes, I assume I don't need them if using the knock outs on the bottom?
Grommets are still required to prevent the cables being damaged by the sharp metal edges of the consumer unit.
Search for "open pvc grommet" for the usual style, or "stuffing gland" for those with better sealing.
Hi John , what's the best way to connect armoured cable to one of these units once I've ran it from the shed ?
Can u take the lighting out on the new rcd board ie if keeps tripping rcd
No. Lighting circuits require RCD protection, as do virtually all other circuits. If it's tripping the RCD there is a fault which must be found and repaired.
@@jwflame as a quick fix couldn't u just put on unprotected section use neutral bar b4 rcd side ie say just to get lights on for night changing skeleton 2moźz 18 ways all the lighting not on a rcd and it's a mess
No new circuits all existing
Hi John, have you ever heard of anyone actually getting into trouble for unauthorised pulling of the main fuse? I know some electricians can be quite cavalier about the whole thing. Is it just an empty threat?
Cool, thanks for the reply. I kinda guessed John didn't really wanna commit with this one for obvious reasons.
if i turn off the large rcd ie the ones with the thick wire coming from the supply in . does that mean that the buzz bar is dead. i want to put a ring main into the shed and i have a spare 30a fuse unit and i am confident that im doing it correctly i just want to make sure when working with mains power
Yes, but you should always confirm dead as it's not impossible for contacts inside switches and RCDs to fail in the on position.
Is 100A the largest single phase supply a DNO will provide?
In most cases yes - after that it's usual to go to 3 phase 100A, and above that it's higher current ratings but still with 3 phase.
However higher capacity single phase can exist, really depends on the electricity network in the local area, what capacity is available, etc.
hi john can you tell me what make and model of fusebox this is please john thanks in advance andy
Crabtree Starbreaker. Still available in 2022, although they are metal now.
Hmm, I would be more concerned about the exposed single core insulation, just below the single pole junction boxes, than about perfectly neat cable routing.
Just looking at this older vid John and ... I have a question pleeze ?
Should the total MCB's current rating (all MCB's added up) never exceed the main fuse or does diversity apply ?
I heard this somewhere... 🤔
😎👍☘️
For domestic use, diversity applies. The rating of the main switch should however be equal to or exceed (1) the supply capacity (the fuse in the cut-out) and (2) the maximum expected load current.
For industrial use, it may not always be appropriate to apply diversity, as in a factory all equipment may be in continuous use during the day/shift.
Do you do a video of how to connect external wiring ie garden shed, to consumer unit
wow in new Zealand we have bigger meters I will have to make a video of a meter board and a consumer unit
Keep up the excellent videos.. very well presented.. and informative.. have a question for domestic installer.. what type of tester you recommend.. kewtech or fluke.. and model..
I have only used Fluke (previously Robin), so can't recommend or comment on other makes.
However other than being able to do the tests required, the main consideration should be that is is designed/built to withstand incorrect use or faults without bursting into flames or exploding.
Are the neutral and ground bars linked in any way?
No, and it's not allowed to link them either.
@John Ward Really? In North America the ground and neutral wires are all connected to the same bar, which is then connected to the main neutral supply coming into the panel. It it also grounded via either the water supply pipe or a metal rod planted outside near the foundation. You should do a video explaining (or reacting to) how North American power works.
Can you use RCD and MCCB in the same distribution box?
Yes, provided they are from the same manufacturer and they are designed to fit into the same box.
I want to have an Electrician run a separate power supply for my stereo equipment. I have been advised that I need a 30 amp supply. Could I run 4 separate cables from the consumer unit so each hi-fi separate has it's own dedicated supply. Is it worth running a separate earth 6mm from the consumer unit to the four outlets that I have in mind.
You could have separate cables for each item, although electrically it won't make any difference.
A separate earth is not required, the earth in the power cable(s) will be adequate, and the earth would only carry current in the event of a fault.
John Ward Thanks for the reply John. I have a couple of issues with the electrics. Firstly when we have been away for a weekend break,on our return we find the whole house has been without power, so I have to push the main power switch to once again have power supply from consumer unit. Secondly I have a couple of power amps, these or one of them seems to make a buzzing noise around 6 am every morning or when my partner turns on the hair drier. Am I right thinking that the amps have dc in the ac supply? Interference on the line. Great informative videos by the way.
The whole house tripping is probably an RCD (with test button on it), in which case it's a fault somewhere either with the wiring or an appliance. Water leaking is a common one, such as outside lights, wiring to garages/sheds, boilers, water heaters and similar.
The buzzing will be interference either through the mains wiring or being picked up by signal cables, speaker cables etc.
The hair dryer should have interference suppression in it but that may have failed. For the 6am one, it is probably something switching on at that time such as a heating system - not necessarily in your house either.
Thank you for replying JW. I know have watched quite a few of your videos & enquired with a training centre about now doing the 17th edition plus another course. I expect it's quite an up hill learning curve, but would help me regarding carrying out electrical works. Can you recommend any up-to-date -books to learn from.
mate i wish u could do a video on how to add a 30amp wire and add a new breaker switch i got a koi pond and need to add a heater but all the decent heaters are 30amp or more so i need to add it i got room on my unit for another 2 switches but not sure how to i got a better understanding after watching this but not 100% accually i just looked again and there is the 2 breaker switches there but theres nothing wrote underneath and they turn off would i be able to run a 30amp electric cable to it it says that it is 63amp max i thinking is the swiches got power running to them so i would have to connect the wire to the switch then would be running is that write thanks
I want to split the consumer unit, so that one half is using the incoming grid supply, and the other half from a battery bank, which is charged by a solar aray. Is this consider good practise? or do I need two consumer units!
Sounds appalling practise.
So if you change the supplier they have to replace the meter? Sounds strange. Here the meter belongs to the local electricity company.
If you change supplier, the new supplier normally takes over the old meter from the old supplier.
If you are unfortunate enough to have a smart meter installed, this often means that the smart meter is no longer smart once you move to the new supplier and has to be read just like an old non-smart one.
Generally, the new supplier is not at all bothered about the meter. They just want to take a reading so they can start charging you and so that your previous suppler can present you with a final bill. The same thing happens when you buy a house.
I have done both and neither time was the meter changed. In fact, it’s still a traditional electromechanical type.
At the moment in (most of) the U.K., you can request a so called ‘smart’ meter. The supply company will then fit one free of charge.
Is it typical to double up circuits on one breaker in the UK? I'm pretty sure thats frowned upon in the US
They are ring circuits, which are commonly used in the UK.
+codemsan - A number of them will be ring-type circuits that have two legs going out in different directions around the installation but forming a ring or loop-style circuit that typically hosts a good number of socket outlets. So like: DB --- SOCKET --- SOCKET --- SOCKET --- SOCKET --- SOCKET --- DB, where DB = a single MCB over-current protection device in the DB for that particular circuit (commonly rated at 32A). Each leg on a "socket ring/ring main/final circuit" is typically 2.5mm2 copper rated to handle in region of 23A (subject to derating rules due to layout, e.g. in walls, through insulation, clipped direct, on cable trays, etc), but with it being wired in a loop fashion to form a ring, presents a circuit capable of almost twice that (e.g. in the region of 40A or more). It's basically a radial circuit with a leg back from the last socket outlet back to the source.
Ohhh derp, i forgot about ring-main circuits! The 32A breaker on 3mil cable should have given it away immediately :P
+codemsan The ones in the video are rings, however it is permitted to have 2 or more wires in a single circuit breaker even if not a ring. Usually happens when circuits are rearranged to make space for a new one, e.g. put 2 lighting circuits onto a single breaker so a larger capacity breaker can the be installed.
how to complately off the off the electricity to work on home wire repair when i off it indicater light still works what it means it is not completely how to completely off it
Hi sir how do u loop ya bass bar fr the line live bcs is using only single wire down no lives why?
Comments on taking time on make inside consumer unit tidy which is just a everyday thing for a descent sparky but you have now probably take an age explaining this
I am no electrician but im trying to save a few hundred pounds. I have the same mains consumer unit. I want to run some power from my house to my shed which is around 30mtrs from my house. Can i run a small mcb consumer next to mains consumer with a isolated switch before drill out.and then run 16awg armoured to shed. Cant find nothing online to simplify this procedure
hi i need the main inlet hean double fuse any idea where to get one
Most electrical suppliers can probably get them, I have never had any need to buy one.
why no conduit for safety protection?
Great video!!!
very good tutorial
This guy is great wow
how do you install an economy 7 system i have no clue how to install it cheers
If you have to ask, get a professional
+Allen Goldsmith Daniel is right. Of course, the very first step is to apply to your electricity supplier for them to provide an E7 facility. Then you'll need a registered electrician to suuply the necessary distribution gear and connect it up.
thanks for the video
Thanks for explicate. România