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  1. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Hello,

    Total newbie here and as you can tell from my name..... I'm definitely not an electrician. I've done a bit of electrical hackery in the past, mostly in cars and a bit of soldering, but this all feels a bit beyond my ability and I'd rather not be electrocuted and die before my 30th birthday. Afterwards..... we can reassess ;)

    Last week, I replaced my bedroom light switch, essentially a standard SPDT light switch with Common Live, Neutral, and Two Switched Live Outputs (L1 and L2), albeit only one was wired up.... with a 21st century equivalent, a 'Smart Wi-Fi switch'. Indeed, I can now turn my lights on from work...... why you'd do that, I'm not sure?

    Anyway, having seen what a trivial task that was, the boss has now decided that we should do the bottom of the stairs too, but that's a whole different gravy train..... for a number of reasons:

    The bottom of the stairs has a faceplate with 3 separate switches.... Switch 1, controls the outside lights. Switch 2, controls the hallway light. Those two are easy, as I'm guessing from a purely electrical basis, the wiring is the same as the bedroom.

    Switch 3....... from what the Internet is telling me, is referred to as a '3-way switch combination' ? So it can be 'live' in either position.

    I vaguely understand the electronics behind this, to a certain degree..... I've not removed the faceplate, but I'm guessing this single SPDT switch will have two wires for the switched lives, one in L1, one in L2.
    When L1 is live, to complete the circuit the upstairs one will have the same combination (or vice versa) and either one can break or make that circuit? Perhaps the dumbest explanation ever, but yeah, it will make sense to someone perhaps.

    That all sounds delightful, but I've looked at the rear of this replacement panel and it's a totally different ball game.

    [​IMG]

    The one above isn't the one I am fitting but is basically the same wiring. We have a neutral far right, common live next, and then we have 3 switched live outputs, L1,L2,L3. I guess the way this device works, is that it's a simple state machine, L is powering the hardware and the software controls which of those are hot and when they are hot, the light will come on.

    By wiring this in, am I going to effectively render the upstairs switch redundant? I assume that the upstairs switch will only work if the downstairs smart switch is permanently on? The same applies to the downstairs switch..... Am I going to be left with a floating live wire? I've read that the easiest solution is to simply rewire the upstairs one to passthrough current at all times and to blank the face off altogether. That doesn't sound clever, or safe to me.

    As you can tell, my knowledge somewhat ends around the time I begin to hypothesise if we can actually fix the issue at hand without killing myself? I've already ordered the 3-way but I can easily use it in the kitchen if this can't be solved. Kitchen is three lovely SPDT's that turn on and off a single set of lights each :) Ahh. Lovely.
     
  2. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    Remember to take some photos when you try it so we can tell you to get an electrician when you do your next post entitled "Help where do all these wires go", at least it will be cheaper then the electrician doesn't have to trace all the wires you are going to find in there. You sure you have a neutral at the switch? I am curious as to how you got a neutral at the switch in your bedroom.
     
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  3. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Love your optimism :D You're almost as optimistic as me!! To be fair, I would always take a photo before disconnecting anything, as I don't want to be in the situation where I cannot revert to my previous position.

    No idea if there's a neutral downstairs. I haven't looked, but I am guessing so.

    The 'neutral' (or is it earth?) was already there in the bedroom. The bedroom light switch was a metal faceplate, 4 wires coming in:

    Red - Live
    Yellow - Switched
    Yellow/Green - Earth? Neutral?
    Blue - ?? (disconnected)

    I removed another faceplate however in a different room, and the wires were:
    Red - Live
    Yellow/Green - Earth
    Black - Switched

    Couldn't see a fourth wire.

    I get the feeling I'm biting off more than I can chew. Might give it a swerve truth be told.

    Regarding a passthrough, the more I think about it, the logical passthrough would be downstairs, rather than upstairs, however the upstairs is a double switch faceplate, not a triple. D'oh.
     
  4. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    I think this thread will get locked very soon. If you really connected the earth as a neutral to your bedroom switch you are in danger as we speak. I think I will short circuit this and suggest you get an electrician in to do what you want with the lights.
     
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  5. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    OK, you're going to have to forgive me, as I'm not an expert and now I'm slightly worried, so help me out here. If I am understanding your point correctly, what you're suggesting is that the previous switch was also dangerously installed, and that I need to get an electrician in? It's entirely possible that this is the case because the house was renovated before I bought it. Large parts of the electrical system was changed.

    Perhaps I am misunderstanding the the element of danger here as well. I assume if there is danger, then I have energized the ground constantly? So, say a bulb went, then even with the light switched off, the metal ground would still be energized. Am I understanding that correctly?

    I can easily remove the 'smart' switch. It wouldn't take more than a few minutes. However what I'm failing to understand from your point, why/how it is dangerously installed, especially as it is using all the same wiring as was previously there? Or whether it's more dangerous than the previous circuit that was there? If so, I will remove it tonight and we can live without it. I really can't be bothered to get the entire house re-wired just for some convenience.

    As I said, I'll whip the new switch out and have the old one back installed in 15 mins, but just trying to understand where the dangers lie here and what I've done wrong.
     
  6. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    OK, so from what I'm reading on t'internet, the blue is usually the neutral and this is what should be connected to the neutral (makes sense that :-\). That leaves the question what do I do with the ground? I'm not bridging it, as I'm aware that is called a 'bootleg ground'.
     
  7. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    I think you need to get an electrician you have opened pandoras box. Although apparently there is hope at the bottom there are a lot of things to get through to the bottom. Anyway your casual description of its earth or neutral suggests you may have mixed them up. You say you took photos of the switch prior to putting on the new one, can we see that? Then we could be more confident in making any statement. The three way switch downstairs is going to be worse. As there will be strapping cables x 2(?) and three twin and earths. Normally, unless recently wired, there is no neutral at the switch, so again I am worried/curious on how you found one at your switch. It is possible but not usually likely. A photo again would help on that one.
    The thing with the downstairs switch apart from the amount of cables is the space available. The switch you are contemplating fitting has a higher profile at the back which will make it even more difficult to fit it in with a switch that will be crammed already and probably they have not thought to put a deeper box in to allow for this.
     
  8. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    I have never fitted one of these but his switch does say neutral (optional)?
     
  9. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Thanks for your help. I genuinely appreciate it. I think I'm going put my foot down on the 3-way and say it's a no-go until I can get a qualified electrician it. I don't do this for a living, it's way over my head. I write software, so I'm essentially playing with fire.... and I'm from Stoke, so we haven't discovered it yet ;)
    This whole thing is clearly way way beyond my knowledge and right now, I'm just keen to get my house safe (again?). Am I right in thinking that if I have connected it to ground, the difference between neutral and ground should be 0, therefore it's not, so I might have energized the entire ground loop on the upstairs lights therefore every ground on that circuit would be live? Permanently? Doesn't sound great.

    I will try and find the photos I took prior to the wire up. Regardless, I will knock off the breaker for the upstairs lights as soon as I get in and remove the Wi-Fi switch, and take some better photos along with how the old one was wired in, which is still sat on my desk. I remember how it was wired in because I knew there was a potential I'd need to go back. It should only takes a few mins to do so. No idea if you'll be online tonight but I'm happy to go without upstairs lights until I get it sorted. Glad I got those bedside lamps now :D

    There is definitely 4 wire cable going in (Red/Yellow/Blue/G+Y). Absolutely positive. So I guess the aim is to identify the blue and G+Y and whether they're ground and neutral or just neutral?

    The problem I had while installing, was when I Googled the colours so I could get a better understanding, there was nothing clearly explaining what each wire colour referred to. I guess it is possible that the previous occupant re-wired with non-standard electrical cable? Like you said, pandoras box.

    I have a feeling when the rewire took place, some efforts was made regarding the hole and 'deepening it'. It is much deeper than previous houses I've been in (indeed I have replaced wall switches before, but not with a smart one) and it also has like a metal cage which I've not seen on other houses before.
     
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  10. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Good question regarding whether the neutral is optional. I will read the instructions again tonight. Assuming I wire it without a neutral, I'm guessing it just won't work as it won't be a complete circuit though?
     
  11. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    The red, yellow and blue of that cable are all likely to be live wires as it forms part of the two way lighting. As previously stated it is doubtful the switch has a neutral in place. Best cut your losses and use an electrician.
     
  12. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    That is the problem with those smart lights they need their own supply so neutral is not optional but required. Which is why the move to putting neutral to switch now.
     
  13. Matthewd29
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    Matthewd29 Regular EF Member

    Location:
    Belfast
    Are you sure that blue is a neutral and it is not a 3core and earth for 2 way or intermediate switching? If there is only 1 blue I would doubt there would be a neutral at an old light switch
     
  14. Matthewd29
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    Matthewd29 Regular EF Member

    Location:
    Belfast
    Sorry I have just realised westward has beat me to it, damn I need to start reading the other comments before writing
     
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  15. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    And yes you haved apprehended the gist of what I am worrying about making the earth live. But then if you have why did the RCD not trip??? Tell me you have an RCD...Although the 3 core colours you describe are not so much used now so when was the refurb? Do you have certs. for the electrical work?
     
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  16. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    That switch clearly states neutral (optional).
     
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  17. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
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    F.H. Electrical
    Yeh indeed it does, I have used some that do need a neutral. That is maybe ok then as the OP has not used the earth then. As he did not need to, phew!
     
  18. Taylortwocities
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    Taylortwocities Electrician's Arms

    Location:
    Oxfordshire
    Further…that fancy switch has only one live terminal to serve the three switched outputs.
    Unfortunately your existing switch will probably be powered from two separate lighting supplies (upstairs and down).
    So it can’t be used.

    Well it could but it needs a whole LOT of rewriting and re configuration of your consumer unit.

    Also I don’t think that switch would work in a 2-way situation unless there is another one upstairs as well.
     
  19. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    I will need to go through the documents that came with the house for when the refurb took place. It was fairly recent though. The previous owner only owned the house for 12 months and we bought it last year. The owner before the previous owner had the rewire as part of a whole house upgrade. So call it approximately 2-4 years ago, 5 at most. It included LED ceiling lights downstairs, modern kitchen lighting etc and extra sockets.

    Regarding RCD, there's a circuit breaker box downstairs, including trips for upstairs lighting, upstairs sockets, downstairs lighting, downstairs sockets, garage etc etc all on individual loops. No the circuit did not trip and is still running as we speak (I can check from my phone). Forgive me, but should it have tripped? I seem to remember a few years ago, people would bridge neutral and earth to give a common ground called 'bootleg ground' and also not have tripped? In essence it's probably what I've done here.

    If the blue is not a neutral and the current installation is dangerous, I will remove the switch and reinstall the old one. I can get an electrician in sometime in the future, but I don't need to rush. However I need to understand whether the old switch is dangerous too.
     
  20. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    I think the bottom line is that switch is not likely to operate the two way switching on the stairs as #18 states. Any chance of a pic for the wiring of the one you have working in the bedroom.
     
  21. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    As to dangerous, unknown, not enough info/pics. It just worried me for a moment when you mentioned neutral/earth somewhat nonchalantly. But it sounds like it is not a neutral anyway.
     
  22. Matthewd29
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    Matthewd29 Regular EF Member

    Location:
    Belfast
    I don't think they had the house rewired 5 years ago, more like 15 at least of theres red cables still inolved
     
  23. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Not only am I dumb. I'm really really dumb. Having actually looked a bit more carefully, I can see that I'm energizing the earth :( The green and yellow is earthing on the metal frame of the holder. I can't believe I've made such a dangerous mistake. Thank you for highlighting this to me.

    Here are the photos anyway, the question is, is it safe for me to reinstall the old switch and what does the blue wire do? Any help at this point would be absolutely wonderful.

    Is it worth me disconnecting the earth to see if it works? On a purely academic level?

    20171113_183053.jpg

    20171113_183030.jpg

    20171113_183002.jpg

    20171113_182951.jpg

    20171113_182620.jpg
     
  24. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    The reason it functions is because you have connected earth to the neutral terminal and I am guessing unlike you other switch this one needs a neutral to function which the earth will do however, that is not the way to go about it and you need to reinstate the original switch. I doubt the unused blue is a neutral, put the original one back but if in doubt get an electrician in to check it.
     
  25. Gavin John Hyde
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    Gavin John Hyde Regular EF Member

    Location:
    Somerset
    Business Name:
    Sulis Electrical Services
    At least the OP seems to accept his limitations and will stop before doing damage which is a rarity as the forum normally gets the visit from DIY dave who is apparently going to use his mate the electrician but is currently on a unicorn riding holiday in never never land.
     
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  26. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Ditch the not so smart switch and reconnect the original as your bottom picture shows.
     
  27. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Oh for sure, it's coming out. I am happy to admit defeat on this one. I definitely need to get a pro in when doing this stuff in the future. I will get a qualified electrician in, probably after Xmas now to install it, if I decide to install it at all. It might not be worth the effort and nothing is more important than safety when it comes to your house, especially not for a bit of convenience!!!

    Just while we're on the subject, how much would/should a good electrician charge to install a neutral cable? Is it a rip-the-wall out job? If so, I think I'll give it a swerve :)
     
  28. shaun1
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    shaun1 Regular EF Member

    Location:
    United Kingdom
    It may be possible to re wire the circuit to provide neutral down the existing cable but that would have to be investigated.

    Also, I think you are confusing Neutral,l and Earth of a 230v A.C. system with 0v/ground in electronics. In an A.C. system, earth is connected to the Neutral at the supply end and to the general mass off earth, but from that point on it is only used as a safety system to make sure that all exposed metal work remains at 0v to earth. The Neutral cable provides a return path for all connected loads. Lighting circuits are often wired with a live and neutral in the light fitting and then a pefmenant live wire is run from the fitting to switch with a switched live running back to control the light.

    As mentioned it is possible to get smart switches that don't require a neutral (these work by sitting in series with the load (bulb) and passing a small current through it even when off.

    There are also smart dimmers that can be wired in at the light fitting, using the existing switch as a control input.

    But as already stated, it would be best for you to find an electrician who is experienced in wiring these smart switches. If you find the right solution it may only involve a couple of hours of labour to get a few circuits wired up to smart switches. All tested and certificates issued.
     
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  29. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    What worries me, having established the earth is energised (possibly) is why did the RCD not trip. I applaud @NotALeccy@NotALeccy your honesty in checking and listening and "owning" up to what is a very understandable mistake in the circumstances. Can you put up a picture of the box which controls this circuit so we could see if you do have an RCD.
     
  30. shaun1
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    shaun1 Regular EF Member

    Location:
    United Kingdom
    The N connector in the switch is only for the switch electronics, which probably only draws a couple of w so may not be enough current to trip the RCD
     
  31. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
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    F.H. Electrical
    True there may not be enough current doing the maths, but it is something I would be inclined to test while I was there, I mean RCD tests to make sure everything is ok with the RCD.
     
  32. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Thanks for the replies everyone. I've reverted back to the old flick switch. Boss isn't happy, but then again I'd rather live than be electrocuted while changing a bulb.

    @shaun1@shaun1, indeed my knowledge of AC is really tiny, as you can tell. The kind of electronics I've done is mostly automotive, where it's a case of live/ground, done.... Much easier than this

    I'll get a photo of the 'RCD' or breaker box or whatever it's called :)
     
  33. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Photo of my breaker box. The blue switch knocks off the upstairs lighting.

    20171113_221424.jpg
     
  34. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    They do not have rcd protection and that Protek device should not be fitted to that board it is not compatible.
     
  35. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    Looks like your time is up on the retest.
     
  36. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Are you saying its unsafe then? Shouldn't this have been spotted on the £700 home buyer survey, bearing in mind I had the full building survey? Just wondering if this is normal on a house or have I been stitched up a bit?
     
  37. PEG
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    PEG Trusted Advisor

    Location:
    Manchester
    Am i the only one wondering if the"boss" is actually the OP's life-partner,or a work place senior figure,unusually interested in bedroom lighting operation? ;)
     
  38. darkwood
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    darkwood It's all about Gmes Staff Member Electrician's Arms

    Location:
    West Yorkshire
    @thuyln2@thuyln2 - Hi, just to explain the forum is based around the UK standards and practices and these may differ from that of Vietnam and any advice given may not reflect your local practices and regulations, please factor this into any advice you take.
     
  39. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    Your installation is not unsafe (subject to EICR!). The sticker on your consumer unit (the photo of switches etc.) says it's due to be inspected last year. So an EICR is due for your installation. There is no RCD protection for your lighting circuits, hence there would be no tripping with the way you have wired your light switch.

    If you look at the switches you have a mixture of different brands. Schneider took over Square D, and now if you want to replace those switches you use a Schneider. The protek as @westward10@westward10 said, is not compatible with the consumer unit. Although of all alternatives protek would not be my choice as I think they are not good quality. Should be Schneider.

    As for the survey, unless you had paid an electrician to do an EICR you would not really know what the state of the electrics were/are.
    I would not beleive a surveyor who told me the electrics are fine in any event. That would be like asking Jamie Oliver if your car is OK. I think if you check the weaselly words used in such a survey you will find that there are disclaimers which tell you; We took your money and told you what we think but don't rely on it, if you do we will insist it's your fault not ours, and if you have enough money to pursue it we are in trouble.
     
    Last edited: Nov 14, 2017 at 9:11 AM
  40. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Indeed.... about a month before we bought the house as well. I should have asked the seller to get this sorted for me, I might have had a solid case to demand it. I never spotted it though. Unless you know what you're looking for, you really don't have a clue.... and I don't. They weren't the best seller in the world though, I won't lie. They would have probably told me to do one.

    Is it worth replacing those switches (not me.... obviously) with modern day Schneider's then? Would this bring it up to 'modern standards' or does it need an RCD too? How much we looking to bring my house up to a safer spec? I do feel a tad duped, as I suppose the previous seller should have done it, but if you're selling a house, you're going to avoid doing any work at all, if possible. Can't blame them.

    With regards to the dumb 'smart' switch. I've had a word with the electrician at work who does all the office wiring and he's going to have a look for me at lunch to see if it can be safely installed. He's installed a few in the office already. He's said, if I have described it properly (which I probably haven't), the 3rd core (blue?) is probably going up to a junction box in the loft area but will disconnected. He said that can be connected to the neutral in the light fitting and that provides a safe neutral. I have a feeling that is what @shaun1@shaun1 described earlier. If that's not the case, then the simplest way is to attach a new wire to the old one and run it up the wall, assuming it's not secured? I think I get what he is saying.....

    He also said the downstairs one could be an absolute nightmare, involving floorboards coming up. That won't be happening. I'll send it back.

    Thanks everyone for your help on this, and I'm very glad that my house is a bit safer now. As for these smart switches, I think I'll recommend giving them a swerve going forward. Do modern houses have neutrals in the wall wiring yet?
     
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  41. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Good idea getting an electrician in and yes most new builds incorporate a neutral at the switch so people can fit smart devices.
     
  42. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Story has a happy ending after all. Had him over, he terminated the earth wire behind the switch and removed the strap which was connecting to the other switch, if I want to return it back to its original state it is easy enough, unscrew and screw it back. He connected the neutral wire from the 4-core into the junction box in the loft above the light fitting, so it's using the same neutral as the light itself. Whole job took around 40 minutes including a cup of tea and that included removing the light fitting, adding a new wire in and going up the loft.

    He did mention that as far as jobs go, this one was on the easier scale. So I can imagine this gets much harder in other cases.

    Attached some photos.

    20171113_223706.jpg

    20171113_223649.jpg

    20171113_223653.jpg
     
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  43. Vortigern
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    Vortigern Electrician's Arms

    Location:
    England
    Business Name:
    F.H. Electrical
    Get and EICR I reckon it will be around £250.
     
  44. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    OK, I'll get that sorted in the next few weeks. :)

    Thanks again for everyone's help on this :D
     
  45. NotALeccy
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    NotALeccy DIY

    Location:
    Staffordshire
    Had a look again at my breaker box, no RCD (googled, so i had a fair idea), however there is a Square D main switch next to it disconnected. Sounds like a rattle to be honest. Not sure how I missed it. I guess this is what they replaced with the Protek?
     
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