Acacia Road......Bananaman reference? God I loved that show as a child! 😊You're a legend and inspiration to us all John. Thanks for the much valued content! Mike.
@Dailymailnewz8 ай бұрын
I think it must be either a mistake or the Electrician may not be informed??? I am sure that they will have a diode connect to the earth so no voltage or current finds its way back, I am pretty sure that is the case, why would someone design something as bad as this?? If you were to connect a diode to it , it will not allow any current or voltage, thus it can flow into it but not the otherway around....And if there is a diod connected to it not to allow the reverse power etc, you can sitll be sure that all earth in a big building will have power as allot of it is flowing to it from leakage current etc, in building where it is no PEN SYSTEM ANYONE DARE TOUCH THOSE BIG EARTH WIRES, THUS THERE IS A PROBLEM IN THE EXPLANATION HERE... UNLESS some one was so stupid that he was totally blind to design a system like that, which I do not belive it is the case, inside that box somehwere there has to be a diode to make sure it does not allow revers power, but all other power on the earth in all system is commong it is leakage current and it is in all building not just for PEN system....
@electrician247 Жыл бұрын
Lots of time and effort gone into that rig John. Well done.
@Swwils Жыл бұрын
Everyone else better step it up 😂
@andyrobinson605211 ай бұрын
I have now watched many of your videos over the last few years and must say that you, sir, are a truly excellent communicator
@DavidWilliams-zw2ji Жыл бұрын
This is the best explanation of the topic that I have ever seen. Many thanks for the time and effort making your videos.
@user-ju6kx5hp1w Жыл бұрын
Just when I thought I'm finally reaching a understanding of why and whats happening. You say "your only scratching the surface and 3 phase is more complex". Excellent demonstration, thank you for your time and effort that goes into making these videos. I've learnt so much from you. Your 1 of the greatest minds in our industry.
@maxmerton Жыл бұрын
I’ve been guilty of disconnecting main bonding clamps from pipes in the past, and not giving it a second thought. This has opened my eyes!
@steve83803 Жыл бұрын
I spent over 10 years working on the distribution networks and dropped neutrals caused everything from all electrical appliances in the properties failing (spectacularly if on different phases) to dead livestock, electrocuted Koi carp and several house fires. Great clear and concise video.
@Dailymailnewz8 ай бұрын
Then why is he afraid to remove my comments??? Think about it the system of PEN was designed by who?? An electrician or a phd engineer? Of course it would have been someone with phd so why would he make such a big mistake???? The system does not allow revers power did you know that, there is diode on the end of it with other protective system not to allow reverse power and john ward and others are going around revearling themselves ha ha ha ha. I have worked in all big buildings like BBC , National Audit office ITV TV building all of them or not PEN system and do you know how much leakage current flows to the earth in those building?? Anyone touching those earth rode will end up dead.... and it is nothing to do with PEN... Now do not remove my comments neither praise me but be thankful for learning....
@russellslater40372 ай бұрын
Superb video, thank you. I particularly like that you show there isn't a single, simple indicator, and one needs to follow the issue to it's furthest extent. Never assume, and never miss an element of safe working to save time.
@stanleyadamson912 Жыл бұрын
Hi John thanks for this video. I work in a quarry and one time after an electrical inspection , it was the next day in fact the asphalt plant operator called and said the plant was acting strange, various things weren’t working and some items had tripped. Anyhow I went up for a look and discovered very strange voltage levels at various points in the electrical panels. I eventually traced the problem which was in a three phase distribution board in the next building. The insurance inspector had disconnected the numeral conductor while testing and he never re-connected it. 🤦♂️ As you say the voltages across various circuits varied like crazy. It’s a wonder something didn’t get damaged.
@skamuk1 Жыл бұрын
Thanks for this, very informative. Something to point out, even if you don’t have any current on your bonding conductor when disconnected at the time of testing, that’s not to suggest it doesn’t suddenly become live when someone down the road comes back from holiday and switches stuff on! I treat ‘earthing’ conductors as if they are live at all times, easier to respect it than be a victim! Thanks again 👍👍
@PardoeElectrical Жыл бұрын
People ask me "is there any KZbin videos I can watch to help me learn about electrical theory?" I say watch John Ward. Very well explained 👏
@jjimmyrjagger Жыл бұрын
Brilliant the way you describe things clearly and in a understandable way , love you videos 👍
@dave-d Жыл бұрын
I remember the first time an engineer from our local supply company said "It's all PME now" and thinking do I trust a remote earth connection managed by the DNO? And here we are! Great work as always John. You are an asset to the trade. Thank you.
@mb633 ай бұрын
Very well explained and thought-out information. Thank you for these educational videos. Nobody does these videos like you do; the in depth explanations, are fantastic, and rare. Sooooo glad you are back JW!👏👏👏
@davidchamberlain2162 Жыл бұрын
A very informative demonstration as usual. I only vaguely knew this. Seeing this practical explanation was fist class.
@fyberoptyx Жыл бұрын
Excellent tutorial as always John
@warrengray610 Жыл бұрын
Greetings John, another great, clear and concise explanation Also very handy use of transformer ratios to lower the voltage , increase the current but safely show the principles,, Very well presented,,, I bet those lamps were getting hot! Thank you for this!
@bluebellelectrical Жыл бұрын
Fantastic video John. I knew the theory, but actually seeing it in a realistic installation, it now all makes perfect sense. Thank you.
@warrengray610 Жыл бұрын
That's very true there's only so much you can visually see in your brain,,, but when it's presented in that fashion it really does make sense
@peterrobinson850 Жыл бұрын
Hi John, From an old spark from the 60's. An excellent tutorial as usual, you definitely put some work in to that rig for the benefit to others, I applaud you. I often thought of this scenario and tried to visualise that having water and gas pipes buried would act as very effective earthing rods at the same time effectively parallel paths conducting current to the neighbours and also carrying current back to the substation at the same time thus would mitigate the need for a separate earth rod for safety to limit the touch voltage, please correct my if I'm wrong perhaps my 75 year old brain is defective also. I wait with exited anticipation for your next video, your and excellent communicator. Peter.
@joken8901 Жыл бұрын
your right the water, gas, and lead sheath on the incoming supply gave you a good earth untill the suppliers changed everything to plastic IEE REGS says it all how many times have they not got it right....obviously everything doesent go back to earth so fit an RCD as close to the meter as you can this will keep john out of your house as he seems to be more interested in whats going on in the neighbours house, mabe they fitted their own meter, and mabe john is colluding with the cartel to take the rest of your rights.
@Tim_Small3 ай бұрын
This is normally true but large currents flowing down supply pipes are obviously not good news particularly with gas. I wouldn't be surprised if pipe joints could end up being a point of high resistance and so local heating. More generally, metal supply pipes are gradually being replaced with plastic. In an increasing number of houses the gas is being disconnected entirely and a heat pump is installed outside, these have metal cases, which are connected to the TNCS supply earth.
@fimbles1015 Жыл бұрын
Amazing video. I would never have even considered this. you turned the principles in to a clear concise demonstration.
@fje1948 Жыл бұрын
What a precise and accurate explanation supported by a superb demonstration, much appreciated. The test setup must have been a lot of work! Thank you John.
@TechOne7671Ай бұрын
That’s a cracking test rig demonstrator John. Tip of the iceberg indeed, three phase brings new problems. Voltages with sizes and angles to add up vectorially, parallel paths, each affected by the magnitude of the current. Reminds me of HND electrical networks from nearly 30 years ago. Looking forward to more of it. All the best.
@peterswinson326 Жыл бұрын
Excellent video as ever JW, probably an issue that will happen more and more commonly as the network ages and not something electricians are necessarily going to be looking out for, can't wait for the horrifying 3 phase episode :)
@warrengray610 Жыл бұрын
Give the man a day off he's already done the rig for the single phase,,lol
@jam99 Жыл бұрын
Then again, in some dwelling/building situations, utilities are going more and more to plastic pipes all the way and so perhaps reducing the overall alternative return path impedance. But then some retrofitted plastic pipes are being fed up inside the existing metal ones (e.g. gas) so you probably still have bonded metal going into the ground. Perhaps even the water conductivity in plastic water pipes can become significant in neutral disconnect fault situations if everything is plastic? As a home-owner, I guess the lower the chance of other dwellings 'helping' with your circuit return in the fault case that just you have a disconnected neutral incomer, the more likely you are to get a shock situation but also the more likely you will find your appliances going 'crazy' or not working. It's a tricky bugger. Definitely worth checking the current on as many bond wires you can clamp around and measuring the potential between the two conductors of any 'earth' connection you disconnect before touching.
@chriswilson7493 Жыл бұрын
Excellent demo, as someone else mentioned obviously you have gone to a lot of trouble in order to create a great explanation, many thanks JW!
@stevedunthorne7376 Жыл бұрын
Superb teaching 'manner' and speed. KZbin needs people like you, JW. Thank you.
@thomasfny10 ай бұрын
As a mature sparky, learning doesn’t come easily 🙈 I would like to both thank and congratulate you on your 2 videos on Diverted Neutral Videos 👏🏻👏🏻👏🏻👏🏻 It explained the subject so, even old “f” like can understand it. All Gas engineers, should be made to watch them! Then they may actually use the lead in their tool bag when they remove meters, instead of a jump lead for their cars! Many Thanks Thomas
@andyb7813 Жыл бұрын
Great presentation John and thanks for all the hard work you put into it
@gbelectricks Жыл бұрын
Perhaps we should all start running on 12V🤔😁 Joking aside you’ve successfully highlighted a very serious problem that will only become more prevalent over time. To truly test for dangerous voltages on disconnected bonding conductors (on a compromised system) we need to reference/ test it to true earth, meaning we need to put a temporary test rod in the ground far enough away form any of the properties in the street!! Who said TNcS was the best earthing arrangement?😃
@CNJNSftw Жыл бұрын
Another fantastic explanation John on a subject a lot of us don't know enough about. Brilliant work on the demo rig!
@timballam3675 Жыл бұрын
Had our gas meter removed. The meter guy had a big red "jump lead" to put across the meter during removal!
@tomthomas8013 Жыл бұрын
As always JW excellent explanation with the fault paths and great effort on the rig, looking forward to the three phase horror show!
@godfreypoon5148 Жыл бұрын
Another good down-to-earth explanation. Thanks, John.
@garthdowie9147 Жыл бұрын
Thanks for taking the time to produce this very educational video . Every day is a school day !
@terrysteel6706 Жыл бұрын
Incredible opens your eyes to what dangerous situations can arise due to a lost neutral or broken connection
@ramzg5402 Жыл бұрын
Hello Mr John, thank you very much
@9111logic Жыл бұрын
It was a very interesting and educational lecture for us all, so thank you very much for setting it all up in such a brilliant way. 🙏
@garyedwards5955 Жыл бұрын
Very interesting came across this recently when the gas board damaged a supply cable while digging. I have a lovely video sent to me by the gas fitter of the spark on the gas pipe lol
@bostedtap8399 Жыл бұрын
Excellent tutorial, impressive setup John. Thanks for sharing
@icarossavvides2641 Жыл бұрын
Very interesting and well presented. I think this has explained a problem with a friends boiler installation AND a problem with contactless voltage sensors. The boiler had been reinstalled in the loft space. When the gas service technician checked the boiler with his contactless voltage sensor, is flashed and bleeped, as did mine BUT when probed with a DMM NOTHING showed! Just goes to show that all these expensive ELCB's, RCCB's etc are absolutely useless in this fault situation!
@dudleyguy42 Жыл бұрын
Brilliant explanation John, very good rig a lot of time and effort put in, well done * * * * *
@eddiefitzgerald5198 Жыл бұрын
That was a very interesting and informative video John. Thank you.
@highgatehandyman6479 Жыл бұрын
I watch all your stuff John. Top bannana. Ill be able to self certify soon and truth is these videos are a valuable resource for life long learning.
@starlighteliane1873 ай бұрын
Thanks again. I've watched this several times, hopefully I will remember it when I need to. I've also sent it to friends. You educate us all
@cliveramsbotty6077 Жыл бұрын
thanks john this was very helpful and informative. i'm a gas man, electricity is weird. i struggle to get my head around it.
@paultutton94437 ай бұрын
I hope that all's well John. Having learned so much from your KZbin content I have my fingers crossed that it won't be too long before we hear from you again - your clear explanations and dry humour are much missed! Best wishes from just down the road in Dorchester.
@TurboTel68 Жыл бұрын
Brilliant rig John! Such a useful and well thought out training aid
@Graham_Langley Жыл бұрын
Good video John. Been an electronic engineer most of my working life so spotting the effects of a broken return connection are second nature. I had considered the effect of a broken neutral here as it has a looped supply, but the water supply is in plastic and there's a galvanic isolator in the incoming gas main so no parallel paths.
@Graham_Langley Жыл бұрын
Correction: Well there was a galvanic isolator on the incoming gas main but it's not there now. Can't find any pictures but you can clearly see where it was as I couldn't paint the wall behind it. Must have been removed when the regulator was changed in 2009 and I hadn't noticed. FWIW the gas supply is in plastic but changes to steel before emerging from the garage floor. They no longer allow joints like this to be underground and I wonder if this video's topic has something to do with it.
@pjeaton58 Жыл бұрын
And is the water in a plastic pipe a conductor ????
@blower1 Жыл бұрын
@@pjeaton58 Not enough of a conductor to be of any concern. Resistance of water in a plastic pipe over just a metre is so high that it won't conduct any appreciable current, let alone the distance to the next house.
@Graham_Langley Жыл бұрын
@@pjeaton58 John's done this in a previous video. The answer was no.
@pjeaton58 Жыл бұрын
@@blower1 Really ? Well I won`t be intentionally touching a metal tap on the end of a plastic pipe fed from a water heater where all ground integrity has failed. Perhaps JW would like to construct a demo of this scenario to prove that it`s OK this time using the full 230vac with 30ma RCD of course !
@nickdunstone Жыл бұрын
Excellent! I look forward to the 3-phase one!
@TechOne7671 Жыл бұрын
Brilliant demonstration and rig, a lot of thought and time has went into building what is an excellent experiment. Can only imagine the calculations on a three phase system with say 20 houses, the variables and voltages would be infinite. Reminds me of college exam problems. All the best.
@tubaman66 Жыл бұрын
Very informative. Makes my TT installation feel like a good thing!
@haldo691 Жыл бұрын
How do you know its TT all the way?
@tubaman66 Жыл бұрын
@@haldo691 No connection between the incoming main and the house earth, which is a staked rod. Water main is plastic and no gas supply, so no metallic connections to another property. Not sure what else to say.
@pjeaton58 Жыл бұрын
@@tubaman66 And is the water in a plastic pipe a conductor ????
@tubaman66 Жыл бұрын
@@pjeaton58 it'll be a pretty rubbish conductor over anything but a very short distance.
@alvaropires6497 Жыл бұрын
Thanks
@cestemshow Жыл бұрын
Great effort John. Great demo. Very difficult to calculate this stuff. So many different scenarios to deal with. Safe working Procedures will be easier to create than trying to calculate whether it's correct or not based on measured values at properties.
@M8d9R Жыл бұрын
Excellent video, helps alot trying to get your head around this. Real world scenario is going to be alot more complex, quite daunting.
@markr9069 Жыл бұрын
Thanks for the great video and the amount of effort you've put in to build up such a great demo
@antonyharding5360 Жыл бұрын
Well done john , Regards antony,Warrington Cheshire..
@williammartinculleton5875 Жыл бұрын
JW at his best, thanks for your time, effort & expertise in producing this excellent presentation ☘️🇮🇪☘️
@EXFElectrician Жыл бұрын
Great Video clear visual representation of what can happen
@chrisccs2112 Жыл бұрын
Brilliant video John!!
@DTELEC2 ай бұрын
The presentation and explanations on this video are Golden
@ianbrede16 Жыл бұрын
Thanks John, excellent part1 but your marvelous demo jig shows how complicated diverted neutral currents can be.
@alanbeard4871 Жыл бұрын
Great Video, made me realise that just checking for currents in bonding conductors isn't that informative and disconnecting a bonding conductor is more risky than I thought. So I have learnt something but now feel even more confused about the subject. But it does show that bonding to a pipe that isn't actually connected to real earth substantially increases risk in open pen conditions. Sounds like the only safe way of doing things is to make sure no one is going to touch anything, disconnect and measure voltage to real earth. Given there are about 400 instances of open pen a year, about 0.002% of houses I wonder how many will actually make these checks.
@grahamwise5719 Жыл бұрын
Hi John, the close where I live in the past the neutral of the 3 phase supply broke, each house depending on the balance of the phase loads either had high or low volts. Many appliances were damaged and repaired free of charge. I now have a earth rod in addition to the supplied neutral. I suppose if it happens again all houses will be earthed by my rod! What about the my house TNCS where the supply cable is lopped out to another house. The water and gas supply here are plastic. thanks for the demonstration.
@timballam3675 Жыл бұрын
Fitted my own earth rod when we were un looped by national grid. Water on plastic so should be good now gas removed.....
@nicknorth360 Жыл бұрын
Excellent video John I could show this to my students. Your rig is superb
@stillstanding123 Жыл бұрын
Step by step, methodically explained. It's an excellent training video. Love the shirt too 😊
@speedbird300 Жыл бұрын
Bloody excellent
@TheMadMagician87 Жыл бұрын
Thanks for the effort to build all that, and for explaining it all and putting the videos together. Very informative!
@cambridgemart2075 Жыл бұрын
We lost neutral on an expensive piece of equipment running on 3 phase 415V, the smaller loads, i.e. all of the control electronics, were wired between a phase and neutral and some of the medium loads like motors, pumps and fans were running from a different phase to neutral. When the equipment was switched on, the electrical cabinet emitted a great deal of smoke!
@deancook2123 Жыл бұрын
Cheers JW great insight into this new electric blind danger - many thanks again 👍
@michaelcostello6991 Жыл бұрын
Great subject explained as simply as possible
@Adam-tn7yk Жыл бұрын
thanks for all the hard work you put into that jig. much appreciated as always.
@bazboy24 Жыл бұрын
This is an eye opener for sure
@dstat79 Жыл бұрын
Wow that’s actually quite scary! Thanks for making this video, definitely something to be aware of 😱
@oasntet Жыл бұрын
I love this demo. So easy to follow. If you can't know ahead of time whether there could be a voltage on everything bonded to earth in the house you're working on until after you disconnect the bonding wire, how can you do that most safely so random residents in the house don't get shocked from trying to wash the dishes? Is there another tool you could put across that bonding link that would alarm the moment the voltage appeared and preferably re-link that connection to prevent shocks?
@Mainly_Electrical Жыл бұрын
@mainly electrical , youtube, to learn my friend
@robertstopford101611 ай бұрын
Brilliant content as always. Love the funky shirt. Keep up the great work John!
@waynestares6512 Жыл бұрын
Thank you John. Your videos are brilliant. All the best.
@GaryCram-l3b4 ай бұрын
Hi. I just watched one of your other videos that shows exactly how a 3 port valve works. The one with the lights showing the flow. Nice video which clarifies something for me. The reason I found your video is because I am in the process (tomorrow) of replacing a Switchmaster 400 with a Tado Wireless receiver. I did this before in another house so have some familiarity. Although that system uses 2 separate vales for the hot water and heating. The system I am installing the receiver to tomorrow, has a hot water cylinder in the airing cupboard, small tank in the loft for the radiators while the cylinder is fed from the large cold water tank in the loft. I think this what you call a gravity fed system (I'm not a plumber). The thing about this system however, is that the controller only offers the following configurations: Hot Water only or Heating and Hot water. But, NOT Heating only. The switches on the controller literally says this so I know it's not an issue with the valve. Which by the way is a Drayton Mid Position (it says MA1 on the unit). This controller I think was installed in 1970 and I have no idea why it could not have been installed with a controller that gives all valve position (Hot Water or Heating. Or both). Ok so here is the issue. According to Tado, once I have followed their instructions, the function of the water flow valve will not change. Basically keeping me in the same situation as before. Can you advise me what I need to do in order to get all valve options on the Tado. As in, should I get a plumber/electrician to just re-wire this ? Surely this should be very straightforward. What do you think ?
@deancleaton3967 Жыл бұрын
Clear and concise as usual, thanks.
@harrischalk2 ай бұрын
Quite eye opening, great demonstration.
@TheBigstve Жыл бұрын
Lovely John. The issue is serious, I think personally all new homes should have the earth electrode being connected with the MET of the TN-C-S as stated a recommendation in BS7671 to help this cause. So many electrical contractors are unaware of the above.
@okaro6595 Жыл бұрын
An earth electrode is like taking aspirin on toothache. It does not to that much,
@Spark817 Жыл бұрын
Nice video John, as usually ✌🏼⚡️
@TheJask101 Жыл бұрын
Fantastic rig John
@clivequinn8978 Жыл бұрын
Thank you J.W., excellent video, certainly an eye opener.
@adrianshingler9783 Жыл бұрын
Great video from a total legend, thanks John! I’m off to buy a clamp on ammeter 😎👍❤️Update with the new ammeter our 45A instant shower gave rise to around 1A in our bonding conductor, will be interesting to see what happens around peak time 👍.
@Michelle-jc7dj Жыл бұрын
Fantastic demonstration, love your videos.
@willrobertson77788 ай бұрын
👍👍👍Definitely the best explanation of this that I've ever seen! I was thinking about how to set up a demonstration of Diverted Neutral Current in a 3 phase system where only a single phase supply is available to run the demonstration - I think I've worked out a way to get an isolated low voltage 3 phase supply from a single phase input with a reasonable power capacity at reasonable cost - let me know if you're interested. Would be great to demonstrate with safe low voltages some of the weird, wonderful and lethal things that can happen with Diverted Neutral Current in a 3 phase system.
@ashvanbro9329 Жыл бұрын
Great rig john great work like always mate
@lordofelectrons4513 Жыл бұрын
Very good video. A very dangerous failure mode and arguably a significant design error.
@sergiofernandez3725 Жыл бұрын
Fantastic video John. Would a smart meter pick up on the broken neutral or not? What about a buried phone cable into the property, could that carry Amps to another property? Also with some coms cable, Could that be connected to a differnce power source (transformer) in the next town along thus using different Supply&Earthing characteristics? I am looking forward to the next episode
@jwflame Жыл бұрын
Meter won't detect anything, as it's just connected to the L&N conductors after the CNE cable is split. Even with the CNE totally broken, current in the L&N will be the same, which is also why RCDs won't trip either. On top of that, meters only measure current in the line conductor, the neutral is a solid link internally.
@timbell5676 Жыл бұрын
The solution is if possible to avoid using PME or combined Neutral earth, and stick to a independent earth/stake with RCD. while the underground supply is more reliable, a overhead system is more prone to the neutral failing on the crimped connection on the overhead and I;m surprised that it is still allowed. Their are many example of where PME or combined earth/neutral is NOT ALLOWED. Outside water taps can be dangerous too, where many plumbers do NOT use plastic or insulation between tap and copper inside plumbing! Thank you John for an excellent video!
@okaro6595 Жыл бұрын
RCDs can and do fail.
@johnburns401711 ай бұрын
@595 The French do not have a main fuse. They have a main whole house 500ma RCBO which doubles as the main switch. They also have normal 30ma RCDs in the consumer unit. So if an RCD fails in the CU the main RCBO catches it. Much superior to the nonsense in the UK. These are available in the UK. About £60-80 to buy. Called _disjoncteur différentiel,_ made by Legrand branded Baco. A search will bring them up.
@christastic100 Жыл бұрын
Very useful demonstration and brilliantly made test rig . It shows is a very strong reason and argument for TT arrangements being preferred for metal services such as gas or water. Makes me wonder if it should be considered as a regulation requirement for all metal service properties to be only TT or TN -S perhaps.
@Mike_5 Жыл бұрын
It has to be said JW that is a very very impressive test rig you have constructed there!! Hopefully that is a copper water pipe cut off there not a Gas pipe though?
@LoftInsulation-pj9dj Жыл бұрын
Props to JW for taking his time.
@Ian78392 Жыл бұрын
Many thanks for another very insightful video. I like many others learn so much from your videos and your in depth knowledge. Just one question: would it be at all possible/ feasible to fit a PEN- fault detection/protection device at the origin of an installation, similar to that of many modern car chargers like the Zappi, that would safely isolate the complete electrical installation in the event of damage to the pen conductor in a tncs system. I am just very intrigued to know if this could help prevent this dangerous situation from occuring and if there is any reasons that this could not be done. Apologies if this is a stupid question it is just something that has been on my mind so I thought i would ask the expert! Many thanks again
@popsingh9381 Жыл бұрын
Hi All i My Self have fitted O-pen fault Detection as Matt:e after DNO service for out Ev chargers & Outdoor Commercial industrial Supply’s feeding Market Stalls & funfair Rides as of Respect to BS7671 pen conductor TNC-S / PME As Stated Guidance Note NO7 My Situation Was Payed Area Or Rd . Remember the Dangers off Of Extraneous Conduct Parts if Converting to TT touch potential. Street furniture !
@jwflame Жыл бұрын
The devices sold as 'pen fault' detection and similar are not suitable for a whole property for various reasons. They are sold as a partial solution to EVSE installations outside, and that is all they are intended for. Will cover these in a future video.
@popsingh9381 Жыл бұрын
Hi John Ward just wanted to say thank for your Demonstration of Diverted Neutral Current 10 / 10 As Commented already 3 phase & Neutral Worse Going back to me O-pen Device unfortunately there’s no place to Go cause ist thing it says BS7671 / Guidance note 7 plus escqr BS7909 the earthing of Pme TN-C-S not to be used to Supply Equipment out doors due touch potential plus likely hood of Open Pen Conductor especially where it is impossible to convert too TT System on hard standing Grd ( it’s not a park soil or Green ) installation has full earth leakage protection including time delay type A plus 30MA front end Rcbos . My only concern would be to Derate the o-Pen Device for touch Voltage 70 Volts to Dry location 50 Volts to 25 volts for wett location . Although as you Quote note Designed for whole installations . As per wonderful escQr plus 1989 electricity at work Regs BS7671 it’s an Engineering Judgement 🤔 Can’t See me using an Safely isolating transformer Not Practical
@Ian78392 Жыл бұрын
@@jwflame Thank you very much @jwflame for the reply, I thought that there must be a reason that this would not be suitable, I look forward to the video covering this issue. You really are teaching many people how things work and showing why we need to do the things we do. It is all very well knowing the correct way to do things but the reasons why is the really interesting bit. The subject of touch voltages is the area I find most interesting but also the most difficult to wrap my head around. How touch voltages are limited to less than 50V and if this is always feasible in most installations. How touch voltages are calculated in the event of a fault, etc really is an area that I believe many electricians would struggle with (or perhaps just me)! I would be hugely grateful if in the future maybe this a subject that you could touch upon, but then again I am sure you have a long list of future videos that you have planned. Many thanks again, it is much appreciated.
@philippuszka7356 Жыл бұрын
Thank you very much for an interesting demonstration! Great explanation.
@mastergx1 Жыл бұрын
Very nicely done. I love the rig with ELV AC. I've never liked the idea of PME because of this possibiliy (what was wrong with TN-S!?). I've never had a broken PEN conductor before but I have had a broken phase on a 3-phase supply (L3 I think). Just making a point that they can and do fail - even though it is rare.
@okaro6595 Жыл бұрын
TN-S is expensive. Also it has a problem with possibility of broken PE. This in itself does not cause any harm which is the bad thing as it goes undetected. Then if you get an equipment failure you get shocked.
@KingsG82 Жыл бұрын
I have always had a concern with TNCS. The guidance should be to fit a separate earth electrode.. especially given new homes use plastic incoming water or gas.
@ollieb7394 Жыл бұрын
Brilliant video as always, cheers John
@julesviolin Жыл бұрын
Amazing demo . Never assume anything ⚠️ Always Test 1st
@mikenco6 ай бұрын
I emailed John. Rest assured, he's simply busy with paying projects! He says he'll be creating new vids soon.
@colinblythe3710 Жыл бұрын
Hi John - I have some 3 phase (5pin) switched interlocks - would they be of any use to you to make rigs up etc I wold rather donate them to a good cause rather than just throw them away ??