Radial Circuits

Поделиться
HTML-код
  • Опубликовано: 22 ноя 2024

Комментарии • 387

  • @johnsouthern1493
    @johnsouthern1493 5 лет назад +13

    I'm brand new to the field after a career change, currently studying in college, but these videos have been exceptionally helpful and informative. A basic drawing illustrating these circuits have given me a crystal clear understanding of the basics.....so thank you, your videos are much appreciated.

  • @UncaBeeTV
    @UncaBeeTV 3 года назад +1

    Popping over here from a link on Ring Circuits. American with electrical background curious about how UK wiring works. Now I know what a Consumer Unit is: Fuse Box or load center as we call them. And where we have black/white/green UK uses brown/blue/green for hot/neutral/ground(earth) in the same way.
    Thanks, John Ward, as you are making things very clear in these vids and I understand way more than I ever got from previous Google and RUclips.

  • @aaddeell22kk99
    @aaddeell22kk99 4 года назад +5

    just started an electrical course, they have given me a text book to learn. That was all they gave me. Very hard to study from just a text book. Your videos simpleminded everything and made everything seem easy. Good video, Easy explanation.

  • @TheMalcolms7
    @TheMalcolms7 Год назад +3

    I'm changing careers and I'm doing a crash course in electrical installation at one of these private 4 week collages.
    Your explanation is far superior to that of my tutor 😅
    Thanks for your video

  • @adydanner
    @adydanner 3 года назад +1

    When talking about lighting circuits at the end "Having switches so you can turn them on and off always a handy feature to have!" John I don't think you realise how good your one liners are. Great videos learnt so much from them.

  • @Raj-ul9my
    @Raj-ul9my 3 года назад

    John your the best, I am on an intense electric course and they don't have time to 1 to 1 teach me what's going on, after whatching this video and the one about ring circuits I get it, your so clear to understand and u don't use stupid cleaver language and your pictures are Fab :) thank you so so much

  • @mechrojo
    @mechrojo 3 года назад +1

    Thanks for explaining those circuits. Following from Sydney Australia

  • @garybennett9552
    @garybennett9552 5 лет назад +7

    Love your videos John, very clearly explained without all the jargon. Superb mate.

  • @Mark1024MAK
    @Mark1024MAK 5 лет назад +2

    The people who dislike ring circuits often talk about the possible wiring overloading if a line or a neutral wire or connection becomes loose and no longer makes contact/good contact or is removed.
    In a radial circuit (as in many other systems) if there is a loose connection (say because a thermal screw was not fully tightened) all the downstream socket outlets may work for months or years after the installation was installed. But at some point, the increasing contact resistance of the loose connection will cause overheating of the terminal of the socket outlet if a heavy load is used downstream of the loose terminal. Which potentially could result in a fire.

    • @eddyr3691
      @eddyr3691 5 лет назад +1

      What you say for the radial circuit is also true for a ring circuit that has broke into 2 radial circuits. All you have done is stack failure modes and ensured that the circuit is underspec, and will continue operating as though all is normal.

  • @joeadam9026
    @joeadam9026 7 лет назад +14

    SIMPLICITY PERSONIFIED. Just as a lady DIYer watching these videos, I can now fit my own extractor fans with timer and add additional sockets. I have learnt so much in such a short time and have saved loads of money but esp time and stress from begging electricians to come and do a very small job like those above. They want big jobs to compensate for just coming out - I don't blame them and now I won't be calling or waiting endlessly / finally blaming them for forsaking me. HOORAY!!

    • @TheGhost-gx5vd
      @TheGhost-gx5vd 2 года назад +1

      Joe adam i love it when you girls get into electrical jobs you have proved that it isn't as complicated as it seems wish my wife would do job's like this (oh and yes I'm a sparky) I do cook and wash the dishes to 🙄😳

  • @kennywallis2003
    @kennywallis2003 2 года назад

    Wow thanks John, a man who can ,explain in such a way that the beginners,are able to digest and understand 👏 👍 you have a new fan, cheers mate, .kenny

  • @johnmathias9892
    @johnmathias9892 5 лет назад +2

    It's still a 2.5mm cable as used for a ring main. The MCB in the consumer unit limits the current below its rated value of 26A

    • @johnbower
      @johnbower 3 года назад +1

      John Mathias, that is an important point to make

  • @vishnuharipersad1816
    @vishnuharipersad1816 2 года назад

    Brilliantly explained videos in a calm clear manner

  • @gjones455
    @gjones455 Год назад

    Very clear and concise video’s John, making it so easy to understand. Thanks very much for sharing

  • @pleekh
    @pleekh 4 года назад +2

    Hi John, very concise explanation. Isn't this adding a spur off a spur....I thought it's not allowed.

    • @jwflame
      @jwflame  4 года назад +4

      There is no concept of spurs on a radial circuit, because the cable is rated appropriately for the circuit breaker or other protective device, such as 26A cable with a 20A circuit breaker.
      Spurs only exist on ring circuits because a single cable could be overloaded, as the cable used is rated less than 32A, but the circuit is protected with a 32A device.

  • @bdans228
    @bdans228 2 года назад

    At last …someone who who can teach electric engineering Clearly ,thank you!!!!

  • @gaulti52
    @gaulti52 3 года назад +2

    Excellent series,very informative and well presented!

  • @alerighi
    @alerighi 4 года назад +1

    In my country radial circuits are done a little differently: instead of looping in and out from sockets all the wires for the various sockets are linked together in junction boxes (one for each room or one for two/three rooms), and then a single wire goes to the consumer unit. In fact looping in and out of sockets is prohibited, the only exception are sockets on the same box in the wall, otherwise you should use a junction box. The reasoning is that this way the sockets is not a part of the circuit and doesn't carry a load. The problem comes when you have a damages socket, where the wires are not secured correctly, and that carries the load of all sockets in the circuit, with the potential to overheat and start a fire. Contact of sockets this way only carry the load of what is plugged in the socket itself. Also troubleshooting is much easier that way, since if there is a fault in a socket is easy to know which one is.

  • @allyg2510
    @allyg2510 9 месяцев назад

    very informative video ,thanks for taking the time to share your knowledge, I find the way you explain electrics make it so easy to understand.

  • @alanporter2694
    @alanporter2694 4 года назад +1

    Thanks, my interest is being cultivated by your videos

  • @Phil_AKA_ThundyUK
    @Phil_AKA_ThundyUK 11 месяцев назад

    This is great. Can't see why you'd ever have a ring main at all nowadays, even if you're changing one our as long as you either use 4mm for the 30 amp MCB on the existing ring you're removing or swap to a 20amp MCB if you're sticking with 2.5mm.

  • @lindamcdonaldcairns9874
    @lindamcdonaldcairns9874 2 года назад

    Thanks John. Very concise videos.

  • @sl0w_racer
    @sl0w_racer 2 года назад

    I have learnt so much watching your videos, thank you!

  • @TurboTel68
    @TurboTel68 8 лет назад +8

    Can we have have loop-in and junction box lighting circuits soon please John, along with your thoughts on these? Thanks!

    • @jwflame
      @jwflame  8 лет назад +5

      Already underway, will be available in a few days.

    • @TurboTel68
      @TurboTel68 8 лет назад +1

      Thanks John! Always enjoy your videos by the way.

  • @Mark1024MAK
    @Mark1024MAK 5 лет назад +3

    Ring vs. Radial
    Which you should specify depends on many factors. What are the expected loads (does the building have central heating, so will plug in electric heaters be used or not, what appliances are expected to be used, etc. etc.). How many socket outlets do you want, both NOW and in the future (when someone decides to rearrange the furniture in the rooms).
    Now draw up a plan on paper to work out the details. I always recommend that you specify more socket outlets than your immediate current requirements, as providing them now is far easier than making alterations later.
    In a rooms where there are plenty of socket outlets, the distance between the sockets will not be that far, so the difference in cable cost between two radials and a single ring circuit will be insignificant if buying drums of cable.
    Properly designed and installed ring circuits are just as safe as radial circuits.
    Ring circuits are more flexible for the end user, as they can plug any normal appliance in to any socket outlet they like. Whereas if 20A radial circuits are used, too many high powered appliances connected and switched on at the same time on one circuit will trip the MCB. Worse if the protective device is a fuse... Fuses have the disadvantage that people can put in higher rated fuses, higher rated fuse-wire, or normal wire or other conductive material. And don’t think that a MCB protected consumer unit can save the day, as I have come across radial circuits run in 2.5mm squared cable protected by 32A MCBs...
    Properly designed and installed radial circuit circuits have the advantage that no fixed wiring cables should overheat. But a poor conductor connection in a socket outlet could cause overheating and may result in a fire. So the argument that a fault will always show up in a radial circuit does not wash with me.
    With a ring circuit, a disconnection or a poor connection could result in a cable being overloaded if multiple high power appliances are in use. But as there are two current paths, it does depend on where the fault is in relation to the circuit wiring.

  • @Robin-Rhys
    @Robin-Rhys 8 лет назад +89

    "Created by lucifer himself" had me chuckling for a while! Thanks for another great upload JW!

    • @Gameboygenius
      @Gameboygenius 8 лет назад +6

      Are you saying you *wouldn't* sell your soul to satan to save a minor amount of copper wiring?

    • @parko1965
      @parko1965 7 лет назад +2

      Kirchhoff the devil

    • @gyrgrls
      @gyrgrls 6 лет назад +3

      Only in lighting circuits. Lucifer was the "angel of light" before his fall. ;->

    • @peteclements6427
      @peteclements6427 6 лет назад

      I lol to at that

    • @aldairzettewachenje9353
      @aldairzettewachenje9353 5 лет назад

      true @@parko1965

  • @CarlosArruda77
    @CarlosArruda77 8 лет назад

    stevieboy1986 spurs with more than one outlet need to be fused "13A" because the load is no longer shared in a ring main. Remember the 2.5mm cable does not support 32A which is typically the protection on a ring main. On a radial circuit with 2.5mm, circuit is protected by a 20A MCB which is within the cables current rated capacity for method 3 clip direct so no need to protect it with a fuse.

  • @terryleaman3038
    @terryleaman3038 4 года назад

    Excellent video JW

  • @aytonbob
    @aytonbob 6 лет назад +1

    Thanks for the videos I am learning a lot from them. I am going to wire up my garage in the future.

  • @ChernoBueno
    @ChernoBueno 4 года назад

    So useful man your help is really helping me at college

  • @simonvazquez6751
    @simonvazquez6751 3 года назад

    Clear no nonsense information !

  • @kopihijaupremiumsista5924
    @kopihijaupremiumsista5924 6 лет назад +3

    This is the info I have been searching for. Very helpful. Thanks a lot

  • @johnburns4017
    @johnburns4017 Год назад

    In France the regs say a radial of 2.5mm cable can supply up to a maximum of *eight* sockets. I have 12 sockets in my living room (two behind the wall hung TV and sound bar alone). In France I would need two radials, each with its own breaker at the CU, for the 12 sockets. Madness. I have one 32A ring circuit serving three rooms and a hall. In France that would be around four or five radial circuits, each with their own breaker at the CU. The CU would be bigger and more expensive as well. All needless expense and hassle, when one ring circuit would do it all.
    Rings are not safe? Have an AFDD at the CU as recommended by the regs.

  • @Mark1024MAK
    @Mark1024MAK 5 лет назад +1

    So is there any reason why star circuits are not used? By a star circuit, I mean a 32A MCB in the consumer unit. 4mm squared T&E cable to a distribution box. The distribution box contains three busbars (one each for line, neutral and earth) each with suitable size terminals, one for the incoming cable and say six other thermals for the outgoing cables (each terminal being intended for just one conductor wire). The socket outlets can be single or double and each is fed via it’s own 2.5mm squared T&E cable from the distribution box.

  • @marctorrades1760
    @marctorrades1760 4 года назад +1

    Thank you John
    I'm just wondering if you could do a video on campervan installation, of both 220 volts and DC voltage
    My son is fixing his van
    And I'm a bit confused myself how to do it from an inverter charger .
    This machine is producing AC and DC
    If you didn't do 1 already
    Many thanks

  • @ironpirate8
    @ironpirate8 5 лет назад

    It might be worth noting that some RCBO's also have an earth tag to connect to the earth bar in the consumer unit.

  • @casper1240
    @casper1240 4 года назад

    Many thanks cleared alot of confusion up alway got mixed up with Ring and Radial circuits cheers

  • @G1ZQCArtwork
    @G1ZQCArtwork 5 лет назад +1

    Hi John. Me being "old school ring mains" I have to question the theory of using that poor old double socket getting used as essentially, a junction box. If those screws are poor, or not tight, it will get hot.
    I have always had a rule of never putting more than two wires in the back of a socket, for that reason.
    That said, a ring main (I know you don't like them for reasons of testing difficulties) lends itself to the convenience of load distribution.
    I understand your concerns over overloading near the distribution board, but this is directly proportional to where the sockets are positioned on the ring, and providing the trip is of the correct rating to protect the cable, that is dealt with.
    David (G1ZQC full licenced Radio Amateur)
    PS we have been using Surge Protection Devices for the best part of a century.

  • @Biggles83
    @Biggles83 6 лет назад +1

    JW you are a legend ! Brilliant stuff

  • @johnburns4017
    @johnburns4017 Год назад

    Circuit design. Tables tell us the maximum current cable rating depending on installation. If a cable is open and clipped to the wall the current rating is high, while a cable embedded in plaster is much lower. In a circuit this is generally mixed as it works its way through the fabric of a house. What do you guys do? Take the lowest derated figure of a circuit? If most of the cable of a 2.5mm circuit could take 27 amps max, but a short one foot section is derated to 18 amps, is the lowest figure taken as the maximum current allowed in the radial circuit, 18 amps. That would mean an MCB of 16 amps on a 2.5mm cable. What do most do?

  • @yvonfem
    @yvonfem 4 года назад +1

    Excellent as usual yes the lucifer pun was brilliant thanks jw

  • @jalilalmteen536
    @jalilalmteen536 4 года назад

    Nice Visio . Could u please wright t the steps for each test
    Like removing light , switches off or on in all type of each test to be carried .
    Thanks again .

  • @mrkingskintim
    @mrkingskintim 4 года назад

    That's a really helpful video. Thanks so much. I have learn allot. I knew it would be pretty simple and your instruction makes it so

  • @thelawnranger4408
    @thelawnranger4408 6 лет назад

    Thanks John, thats the clear plain English answers I was looking for to assist me in my garden summer cabin project as far as 240v sockets go.
    Does anyone have any helpful vid links to helping with our plan to have LED lighting and USB charger points running on a separate 12v system via a couple of hefty car batteries fed from solar panels or trickle charge from mains if needed.
    Many Thanks

    • @jwflame
      @jwflame  6 лет назад

      Unless you are determined to have the solar panels for some reasons other than cost, or you can get the parts for free or next to nothing, don't bother. The expense of the panels, batteries and charge controller will far exceed any tiny savings from not using 240V power for lights.
      Julian Ilett has many videos on solar power: ruclips.net/user/julius256search?query=solar

  • @LAnonHubbard
    @LAnonHubbard 5 лет назад +1

    Your explanation of the current flow in the CU (around 10:20 onwards) I found especially handy, thank you. The rest of the video was great too. Seeing a bunch of things connected with wires can be confusing until one pictures the current flow.
    What you said about flicking the switch on a breaker isolating the line only (and not the neutral) was interesting. If you wanted to isolate a circuit (and just that circuit) properly, would you also disconnect the neutral from neutral bar, or remove the MCB/RCBO from the CU completely? I'm asking for a friend (!) who is remodelling his en-suite.

  • @PsyMongazoid
    @PsyMongazoid 6 лет назад +2

    Are YOU hoping for a career in the RAF, perhaps as a technician or Officer? Good, then pay close attention to this man's bearing, tone, and dry humour. This will be expected of you during every crisis and in the Officer's Mess afterwards.

  • @lengthmuldoon
    @lengthmuldoon 4 года назад

    He does voice overs for airline pilots with dodgy middle east accents his delivery of "this is your captain speaking" can't be matched

  • @kbcbala
    @kbcbala 6 лет назад

    Great video, simple explanation. Well done

  • @tobydwyer5602
    @tobydwyer5602 5 лет назад

    Love your videos John Ward! 1st yr apprentice Australia

    • @chrisjheath1768
      @chrisjheath1768 5 лет назад

      I wished videos like this were available back when I was an apprentice. Best wishes for your Electrical career.

  • @sean999ification
    @sean999ification 8 лет назад +1

    Thanks JW.

  • @muawiajarrah1901
    @muawiajarrah1901 7 лет назад +1

    Thanks John great informative videos

  • @Sunny-3
    @Sunny-3 Год назад

    Thank you for all your great Videos JW.
    Can you / anyone please let me know what the max length of the cable run (2.5mm) can be for a Radial?
    Another question, if the cable is going through insulation, what size cable and mcb would be required?

  • @misribanda5555
    @misribanda5555 2 года назад

    Wonderful man.. Thanks heaps

  • @Tangobaldy
    @Tangobaldy 8 лет назад +1

    it's like having JW in my house as I got nice new 4k tv

    • @UCCLdIk6R5ECGtaGm7oqO-TQ
      @UCCLdIk6R5ECGtaGm7oqO-TQ 8 лет назад

      But the video is only in 1920x1080p maximum, so your display will be stretching it 2x both horizontally and vertically to fit (3840x2160).

    • @Tangobaldy
      @Tangobaldy 8 лет назад

      9ff70f96 I was waiting for a comment after I posted. My TV upscaled video. It's quite impressive viewed on 4k. Much better than 1080p on my old tv. Sony sure know how to fill in the blanks

  • @BerkeleyTowers
    @BerkeleyTowers 3 года назад

    I've just had the first fix done......... So, if the final leg of a ring back to the CU is disconnected and down rate the MCB to 20A (which is more than adequate for me), I'm left with a radial. If I read it right, the advantages would be more flexibility for expansion in terms of spurs off it (if needed) and a lot easier to test?

  • @kickpublishing
    @kickpublishing 7 лет назад +4

    I admire a man who slopes off to a quiet room to proudly display his organ on the Internet

  • @Josh-vp1hw
    @Josh-vp1hw 4 года назад

    This is how we do things in the States
    120V , 20 amp , #12 conductor (line, neutral , ground) allowed up to 10 sockets on a circuit, same for lights. We call this a "parallel " circuit not a radial .
    A "Ring" circuit would never be allowed wound be deemed a fire hazzard and illegal.
    Cheers from the States
    A "Ring" circ

  • @Ricky-zj6sy
    @Ricky-zj6sy 5 лет назад

    As a professional electrician I can confirm that ring final circuits are dangerous, over the years I have found all manner of serious issues with them. Cross wiring of course being the most serious where four ends of two separate rings are wired together, this effectively creates one ring circuit fused twice and supplies over 60 amps! A short circuit here would have enough energy to melt the twin and earth cables and possibly even ignite flammable building materials. At best it could blow the service providers main fuse.

  • @davidmg1925
    @davidmg1925 5 лет назад

    Good videos. I'm learning a lot.... in a stress free way.

  • @insoft_uk
    @insoft_uk 6 лет назад

    They used radial years ago, they moved to ring and the a new plug was used, as it needed a fuse for safety and now looks like we’re doing a u turn will we go back to the old 2A, 5A and 15A plugs I wonder

    • @Mark1024MAK
      @Mark1024MAK 5 лет назад +1

      You do know that over time humans always HAVE TO CHANGE things. Especially politicians and people who pretend that standards HAVE to be changed. In the real world, it is rare that the principles change. It’s just that people’s perceptions change. Which is correct, driving on the right, or driving on the left?
      Your particular use and specifications should determine if a ring or a radial is more appropriate. I would argue that in some cases a star arrangement would be better, but that’s another story...

  • @Mavrick36
    @Mavrick36 4 года назад

    Thank you JW

  • @paulmcmurtrie
    @paulmcmurtrie 8 лет назад +1

    great video, thanks for making things so clear

  • @naseemmir7590
    @naseemmir7590 6 лет назад

    Thanks for you videos watched in the past. Excellent the way you explain. Real tutor.
    Have you got any video regarding installing a grid control switches in the kitchen. Much appreciated

  • @joeoreilly5561
    @joeoreilly5561 7 лет назад +2

    Hi JW..just ofund your great channel...and I agree with Robin Jones..your "Lucifer" comment gave me a good laugh

  • @simonmartin4599
    @simonmartin4599 5 лет назад

    When a radial circuit goes outlet to outlet, the final outlet is often located in a nearby location to the first. I had thought about if it is a good idea to add the connection between the first and final circuit to complete a loop. This way you can prevent arcing if a wire breaks in a similar way to ring mains. Or perhaps create extra redundancy in the system. There is nothing in BS7671 about it though. Would it cause an installation test result failure?

  • @WhyIMan-hh2tz
    @WhyIMan-hh2tz 2 года назад

    Can use use a distribution board ( plug on neutrals ) as a consumer unit ( Schneider Acti9 )

    • @jwflame
      @jwflame  2 года назад +1

      Yes. A kit to convert them to single phase is available.

  • @bikerchrisukk
    @bikerchrisukk 5 лет назад

    Thank you John.

  • @colinwhorton5507
    @colinwhorton5507 3 года назад

    Thanks very much for that John - not a fan of ring circuits then?

  • @davidwebb2318
    @davidwebb2318 7 лет назад +1

    Really interesting and a great video. What is the purpose for using RCBOs instead of just a circuit breaker in the Line (Live)?

    • @TheEulerID
      @TheEulerID 5 лет назад

      An RCBO provides protection for both overload and where there's a fault to earth. So, if a person accidentally comes into contact with live power, it only takes a few tens of milliamps to get a lethal shock. An RCBO (or and RCD/GFCI) should trip before the current reaches fatal levels. Also, it will trip on certain sorts of appliance faults. For example, if water in a washing machine or kettle leaked into the electrics, either of which might end up being dangerous even though they don't pass enough current to trip the overload.

  • @MendipBeeman
    @MendipBeeman 5 лет назад +1

    Hi John, Great videos, helped me loads over time. Any advice/videos on wiring a 32Amp 4 Pole Rotary Isolator switch which I have to install, single phase 230v. It's for a compressor which takes a high surge at start up.

  • @buttonman6262
    @buttonman6262 2 года назад

    In my garage I have a cable running from the CU into a 3-way junction box and then out to two double sockets. It was installed by the previous owner but I need to add another socket. Do I need the junction box?

  • @peterryan7827
    @peterryan7827 3 года назад

    I just need to ask is this exactly the same as a tree radial,Someone has mentioned to me this phrase,or is this something completely different,great video and thanks again,

  • @trueriver1950
    @trueriver1950 5 лет назад

    5:00 if there are repeated branches then a better name for the result would be a tree rather than a radial (though of course the radial regs still apply)

  • @KarlHamilton
    @KarlHamilton 4 года назад +1

    Does a lighting circuit always have to be on a seperate breaker? It's for a garage so will only be a few bulbs.

    • @jwflame
      @jwflame  4 года назад

      No, another option would be a 3A or 5A fused connection unit from another circuit such as the sockets.

    • @KarlHamilton
      @KarlHamilton 4 года назад

      @@jwflame Thanks mate.

  • @jonessg3
    @jonessg3 6 лет назад

    I've never seen an RCBO with the neutral tail coming out the side. That would prevent installation in adjacent position on the DIN rail. The RCBOs that's I've seen have the neutral tail (and usually a functional earth) emerging from the underside.

  • @jackjill3205
    @jackjill3205 6 лет назад

    Electrical Showers connected to RCB at the consumer unit

  • @chekaphski
    @chekaphski 5 лет назад +1

    Multiple 13 amp sockets on one 2.5 t&e ? what is the difference between that and and a damaged ring main?

    • @jwflame
      @jwflame  5 лет назад

      Radials - cable rating is more than that of the circuit breaker, such as 26A cable on a 20A MCB.
      Ring - 26A rated cable with a 32A device, so when broken, overloading and damaging the cable is very likely.

  • @davidrastall1745
    @davidrastall1745 4 года назад

    Really helpful video m8,cheers.

  • @MrSpotlucy
    @MrSpotlucy 4 года назад

    great vidio but ive missed some thing some were whats the difference between radial and spurs?

    • @jwflame
      @jwflame  4 года назад

      Radial is any circuit that starts at the consumer unit and goes to one or more sockets, items of equipment or anything else - the vast majority of circuits are radials.
      A spur is a socket or fused connection unit connected to a ring circuit with a single cable.

    • @MrSpotlucy
      @MrSpotlucy 4 года назад

      @@jwflame thanks for the reply and making sense of wiring for me

  • @dilligaf2386
    @dilligaf2386 5 лет назад

    I thought you needed to put in a 13amp switched to protect the cable if you want spur and spur or is that just with ring circuit

  • @caaaarter
    @caaaarter 6 лет назад

    Presumably if you found there wasn’t continuity between a ring circuit you could replace the MCB with a 20amp one and everything would be safe and dandy again?

    • @jwflame
      @jwflame  6 лет назад

      20A would avoid overloading the cable, but if an existing circuit no longer has continuity it suggests a loose connection or cable damage, both of which should be repaired to avoid further problems.

    • @TheEulerID
      @TheEulerID 5 лет назад

      @@jwflame I have seen electricians claim that one way round a broken leg on a radial is to disconnect that leg and convert the ring into two radials with 20A breakers. Perhaps if somebody has driven a nail through a cable in an inaccessible spot.
      I've no idea if that's actually a legitimate approach though...

    • @jwflame
      @jwflame  5 лет назад

      Yes, that can be done. If a section of cable is damaged it would be disconnected at both ends leaving 2 radials, which could either be reconnected as 2 separate circuits, or 1 circuit. 20A or 25A is usually ok, unless the cable is installed through insulation or similar.

  • @johnjgraphicdesigns
    @johnjgraphicdesigns 5 лет назад

    Surely you cannot wire a shower circuit the same as a cooker. Should a shower not be wire via an RCDBO or similar?

  • @TillerQueen
    @TillerQueen 3 года назад

    Thanks for these really great videos, although I'm still a little confused about one point. In your videos on ring circuits you mentioned that a ring was able then to carry 32amps so I understand having a 27amp breaker would be ok, although the problem is that if there was a break in the ring the cable would be taking more current than it's intended. So in this case how would a radial circuit be able to carry more current? For example, if I had 2.5mm2 cable in a radial circuit with a supply that carries 32amps would that be a problem?

    • @jwflame
      @jwflame  3 года назад +3

      The basic concept of a circuit is that the cable is rated higher than the circuit breaker, so the breaker will trip before the cable is damaged.
      A ring is a special case as there are 2 cables, which is why cable rated less than 32A can be used with a 32A circuit breaker. Only valid if the ring is intact and there are 2 paths for the current to flow.
      For everything else, the cable must be a higher rating, so for 2.5mm² cable the usual choice is 20A or in some cases 25A. If a 32A radial was required the cable would need to be at least 4mm².

    • @TillerQueen
      @TillerQueen 3 года назад

      @@jwflame Thank you, that's very helpful.

  • @robjenkins8358
    @robjenkins8358 3 года назад

    Been enjoying a JW afternoon's education and nearly missed the Lucifer accreditation. Had to take time out for a laugh.

  • @1414141x
    @1414141x 5 лет назад

    HI John You make some great videos - well explained and understandable. I have been looking for certain info on RUclips but not found a video that supports this. This is if you move into a new house there may be lots of sockets in the rooms. These may all be fed by one feed from the consumer unit in an older house or may have separate ring mains - one for upstairs - one for downstairs and maybe one for the kitchen, in newer build properties. Here is what I would like to find out......What method would you use for tracking the run from the consumer unit to the first socket, and then the second, third and so on. So you could produce a realistic map of the ring main ? Without having to rip up floor boards and being totally confused with the myriad of wires you will find ! Is there a simple way to
    do this ?

    • @jwflame
      @jwflame  5 лет назад +1

      If you really wanted to do that, then disconnect the wires for the circuit at the consumer unit, temporarily connect L&E together in one of the cables at the consumer unit and then check resistance between L&E at every socket. Resistance will increase as you get further away from the L&E link and be greatest at the other end of the cable.
      Same can be used for radials, the highest resistance will be furthest from the consumer unit.

    • @1414141x
      @1414141x 5 лет назад

      @@jwflame Many thanks John.

    • @Mark1024MAK
      @Mark1024MAK 5 лет назад

      Chris Ward - Note that in some properties, the ring circuits may not be one per floor. But instead each circuit may run via the ground floor ceiling/first floor void and run down to sockets on the ground floor and up to sockets on the first floor. For example if you have two circuits, they may be separated into two, one feeding the front rooms with the other feeding the back rooms, or East / West or North / South etc...
      If you want a quick way of tracing live circuits, hire a CAT scanner. Power down and isolate (including neutrals) all circuits except the one you are investigating. Then plug in a suitable load (such as a heater) at the furthest point from the consumer unit on that ring circuit. Then by using the CAT scanner, you should be able to get an idea of where the cables run. Confirm by using the method outlined by John, as the CAT scanner method is not always accurate if multiple cables run in parallel. Alternatively, also fully isolate the circuit you are investigating (line and neutral) and separate the wires from each other at the consumer unit. Then connect a ‘tone generator’ between one wire (either line or either neutral) and the main earth in the consumer unit (NOT the circuit’s earth wire). Set the CAT scanner to the appropriate mode to detect the output from the tone generator. You should now be able to trace the cables. Again, if the cables from the same circuit run in parallel, it is not possible to determine which is which, so again, use John’s method to confirm.

  • @ronaldlaing9447
    @ronaldlaing9447 6 лет назад

    JW
    Do you have to earth bond between the metal back box and the socket earth terminal on a 13A radial or ring circuit given that they are wired in T&E 2.5mm cable, in order to be compliant with BS 7671.
    I was led to believe that sockets wired this way did not need to be bonded to the back box as they will be bonded through the fixing screws.
    And only if wired in conduit they would require to be equipotentially bonded. ?
    Can't seem to identify in Regs !

  • @electricalstuff259
    @electricalstuff259 4 года назад

    Would i be right in thinking then that you only need a real expensive tester and additional course to be able to test and inspect in the UK, since nowhere else does rings and so continuity testing would never be relevant because a fault would just mean the radial circuit would just stop working past the point of breakage?

    • @jwflame
      @jwflame  4 года назад +1

      All circuits need to be tested, the only difference with a ring is that it requires some additional tests to confirm it is actually a ring.
      Continuity testing is always required, as it's essential to confirm the CPC (earth) conductor is continuous. If not everything still works but in the event of a fault, exposed metal parts would become live.
      Things working is not the same as it being safe.

    • @electricalstuff259
      @electricalstuff259 4 года назад

      @@jwflame I see. Thanks for clarifying.

  • @NigelBachmann
    @NigelBachmann 4 года назад

    I have a 300/500V cable coming out of my consumer unit running to a single double socket, 2.5mm possibly. Is this ok to extend into a radial circuit for washing machine, and general utility plugs for kettle etc.? Thanks. Excellent video btw.

    • @jwflame
      @jwflame  4 года назад

      It can be extended, provided the protective device (fuse, circuit breaker) is suitable for the cable. If it's 2.5mm², usual choices would be a 16A or 20A. Additional sockets also require RCD protection.

    • @NigelBachmann
      @NigelBachmann 4 года назад

      John Ward thank you

  • @theenavijayan5753
    @theenavijayan5753 6 лет назад

    I think most radial circuits are wired individually from an MCB to 1 receptacle or maximum just 2 which means if we have 5 mcbs we would have 5-10 receptacles, right?

    • @jwflame
      @jwflame  6 лет назад

      That may be done in some countries, but not in the UK. One circuit can have multiple outlets/receptacles and usually does.

  • @willkndy
    @willkndy 3 года назад

    Hi John, if you were wiring a new kitchen would you choose 2 radial circuits over a ring main? Assuming that the cooker is on its own circuit also. Thanks.

    • @FrodoOne1
      @FrodoOne1 3 года назад

      While John has not yet answered you, his remarks at 0:30 and 12:50 in this video and his comments in ruclips.net/video/hZN6hiGLtrE/видео.html should give you a fair indication !

  • @rshelectricalltd8440
    @rshelectricalltd8440 5 лет назад

    Hi John only watched a couple of vids but would like to ask if you have covered initial verification such as checking main bonding before starting any electrical works, 30mA RCD protection and correct operation, of any RCD'S ie disconnection times with a compliant and calibrated meter >300mS and >40mS etc. Obviously you would also be advising on installation methods, maximum earth loop values for the protective device/fuse and breaking capacity to ensure circuit/installation complies with tables in BS7671 and guess you also advise how to complete the correct certification as required as detailed now in BS7671 2018 as from 1st Jan 2019 including AFDD arc fault detection devices....

  • @yechihast
    @yechihast 4 года назад

    Great vid as always. Thanks a million. Question: Can we add a junction box between two sockets to branch out for more outlets?

    • @jwflame
      @jwflame  4 года назад

      Yes. If the junction box is to be concealed, it needs to be a maintenance free type.

    • @TechnologyGuy223
      @TechnologyGuy223 3 года назад

      @@jwflame Would this be notifiable under Part P?

  • @Robert-ts2ef
    @Robert-ts2ef 3 года назад

    What size mcb and cable is required for a series of sockets? Surely you can’t have an unlimited number of sockets on a radial circuit such as a kitchen where you might have a 4 slice toaster plugged in and a fast boil kettle and maybe a food mixer etc all going at the same time? Do you have to use a diversity factor to size the cable?

    • @jwflame
      @jwflame  3 года назад

      There is no specified limit for how many socket outlets can be installed on a single circuit, but common sense will indicate a sensible number before it's necessary to have additional circuits.
      Cable rating must be greater than the circuit breaker rating so that the cable isn't damaged by overload, but other than that the only limitations are whether the cable will physically fit into the socket terminals.
      2.5mm² is a commonly used size of cable, but 4mm² is always an option, all BS1363 socket outlets have terminals large enough for 2x 4mm² conductors, some can accept larger sizes such as 6mm².

    • @Robert-ts2ef
      @Robert-ts2ef 3 года назад

      @@jwflame thank you for your reply. However as an example if you have say 6 x 13 amp sockets on one circuit, what determines the cable size and breaker size if most of them are in use? That’s why I asked if diversity was taken into account?

  • @1414141x
    @1414141x 5 лет назад

    For radial I believe you use 4mm cable ? And what does the RCBO do , I did not really grasp that ? tks

    • @jwflame
      @jwflame  5 лет назад

      RCBO is a circuit breaker and RCD combined into a single device.
      Almost all circuits are radials, cable size required depends on the rating of the circuit breaker or fuse.

  • @emanuelecimino2276
    @emanuelecimino2276 7 лет назад +1

    Shouldn't a fused spur be used when breaking into the radial?

    • @jwflame
      @jwflame  7 лет назад +2

      No, only on a ring where a single cable is undersized for the circuit fuse/breaker.
      Radials are designed with a single cable of proper size for the particular fuse/circuit breaker.

    • @ferventheat
      @ferventheat 7 лет назад +1

      Thanks for your many helpful replies.When you explain it it all makes sense.
      After 1 week of electrical 'training' at an approved centre, my head was done in...

  • @siggyuke
    @siggyuke 6 лет назад

    Excellent! Many thanks.

  • @SteS
    @SteS 4 года назад

    Hi John, must of watched this video a dozen times. What connection method would you use in an existing installation and I'm breaking into an existing socket so there'll be 3 2.5mmsq at the one location. A deep backbox and take tails of 3 wago connectors for the line, neutral and cpc? Or do it like your video?

  • @NordenEngineering
    @NordenEngineering 4 года назад

    Great video however no mention of cable size or circuit breaker size for radial socket circuits

    • @jwflame
      @jwflame  4 года назад

      Cable size depends on the installation method and the protective device. Anything from 1.5mm² upwards.

    • @NordenEngineering
      @NordenEngineering 4 года назад

      @@jwflame Great videos

    • @joedixon2864
      @joedixon2864 4 года назад

      NO No NO. 2.5mm2 minimum for 20a breaker. 4mm2 for 32a breaker. Each socket has fused 13a plugs.
      Others e.g. imm. Heater should have a 13a spur unit.
      Covered in the regs.
      I'm afraid the supercilius John Ward is not the expert he purportes to be.
      . Read the Regs. Electricity is not for amateurs.

  • @RWATraineeElectrician
    @RWATraineeElectrician 4 года назад

    Thanks for sharing 👍

  • @MT_T991
    @MT_T991 7 лет назад +1

    Recently on a site with a more qualified spark telling me I can't just spur of a radial as youd overload the cable as it's a new circuit, so he pursued his ring and struggled to get 2 cables through a place one cable would walk through
    I normally run 20amp bed rooms and sitting rooms then 32amp 4mm in the kitchen
    Is this the quality of modern day colleges John?