so try to keep it simple and not use long complicated words that only electricians would use...
How easy is it to replace a CU/do a rewire?
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From a DIYers point of view I understand what you are trying to achieve with this thread but to be honest I'm not sure it'll work, at least not as a series of questions many of which can be answered in some fashion by someone who thinks they know enough:
I'm being silly but the questions don't force me to consider that I am out of my depth or even scare me particularly. Perhaps a better approach would be to reverse everything and come from the approach of (some of) the things a qualified person would take in to account and why and what happens if you get it wrong.
Maybe the questions are just too high level and read more like a "well you're not an electrician then" (which i know is the partly the aim) but perhaps asking lower level more detailed questions would illustrate that there is more to it than you think - for example:
(Excuse the questions and the answers - as I said I havent a clue what I'm talking about)
Do you know how to ensure your cables dont melt when you run them in insulated walls? - You need to know about bunching, derating, thermal insulation (with technical terms added!), you'll need access to xyz document to do it properly
Do you know how to ensure your RCDs actually disconnect quick enough to keep you alive? (OK I dont know the answer but I've seen things like R1+R2 and Ze etc mentioned)
and how to test that they will? (You'd need calibrated cattle prod, large heavy guage doodad and some butter)
Do you know how to route a cable so that you dont kill people putting up pictures, and also maybe stop yourself being prosecuted for working illegally? (There are defined safe zones where cables need to be run, there are cable depths and mechanical protection and all of this varies depending on whether the circuit is RCD protected or not)
Do you know how to stop your kids getting electrocuted in the bath when they touch the hot tap? (You need to understand bonding, supplimentary bonding(?), routing of cables)
These are just some of the things you need to understand, get right and test with the right equipment to have any chance of knowing your newly installed CU/Wiring is actually safe and not a death trap waiting to kill someone. If you can't do all this then don't gamble.
Something that approaches it from that angle but with a lot more technicality to the answers would seem to me to have more chance of success.
Well whatever is there I guess, I mean, there's a couple of wires aint there? and this green one I'll just use them.
My mate said just pull the big fuse out
Dunno about that, just copying what's here already, this ones a little flat cable, this ones a medium flat cable and this ones a big fekker, hold on I'll pop down to Homebase and find some the same
Hmm not sure, but I was planning to put them where I need them and then plaster over
Ahh I know this one... everything! see thats how I got into this in the first place, the electrician said I'd end up needing a new CU because I needed RCDs but he wanted too much
Well I was planning on turning it on and seeing if all the sockets and lights worked no?
I'm being silly but the questions don't force me to consider that I am out of my depth or even scare me particularly. Perhaps a better approach would be to reverse everything and come from the approach of (some of) the things a qualified person would take in to account and why and what happens if you get it wrong.
Maybe the questions are just too high level and read more like a "well you're not an electrician then" (which i know is the partly the aim) but perhaps asking lower level more detailed questions would illustrate that there is more to it than you think - for example:
(Excuse the questions and the answers - as I said I havent a clue what I'm talking about)
Do you know how to ensure your cables dont melt when you run them in insulated walls? - You need to know about bunching, derating, thermal insulation (with technical terms added!), you'll need access to xyz document to do it properly
Do you know how to ensure your RCDs actually disconnect quick enough to keep you alive? (OK I dont know the answer but I've seen things like R1+R2 and Ze etc mentioned)
and how to test that they will? (You'd need calibrated cattle prod, large heavy guage doodad and some butter)
Do you know how to route a cable so that you dont kill people putting up pictures, and also maybe stop yourself being prosecuted for working illegally? (There are defined safe zones where cables need to be run, there are cable depths and mechanical protection and all of this varies depending on whether the circuit is RCD protected or not)
Do you know how to stop your kids getting electrocuted in the bath when they touch the hot tap? (You need to understand bonding, supplimentary bonding(?), routing of cables)
These are just some of the things you need to understand, get right and test with the right equipment to have any chance of knowing your newly installed CU/Wiring is actually safe and not a death trap waiting to kill someone. If you can't do all this then don't gamble.
Something that approaches it from that angle but with a lot more technicality to the answers would seem to me to have more chance of success.
Are there any long complicated words in the questions suggested?
Abbreviations used by electricians are usually more of a problem for non electrical folk. 
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number 10 is a bit iffy..
"Extraneous conductive parts..." where "metal parts that may be earthed such as pipes" would do the same..
and some of the others are a bit verbose...
"Extraneous conductive parts..." where "metal parts that may be earthed such as pipes" would do the same..
and some of the others are a bit verbose...
D
dextrous
Marx spent years trying to finish Das Kapital, and compared to replacing a CU, his task of trying to change the world sounds easier. So it looks like it may take some time before you boys get the finished wiki just right
P
PrinceofDarkness
This is a rather silly topic, if you don't mind my saying so, gentlemen.........
It completely defeats the idea of a 'here and now', ongoing discussion for a live forum.
I've no doubt, BAS, that you're well intentioned, and that you're quite the gifted amateur with a good deal of (non-practical) knowlege. But I've found in the past that you've had an unrealistic expectation - and a certain contempt for other DIYers.
The answer is not to put the thumbscrews on would-be electricians by such interrogation, but to steer them through the particular task of the moment, whether it be a CU change or a simple light switch problem - in order that they do the work properly without putting anyone at risk.
This can only be achieved 'live' - and not by some great tome lost in the 'sticky' section..........
Yes of course, I'd be happy to deal with your retorts. Fire away.......
Best wishes,
Lucia x
It completely defeats the idea of a 'here and now', ongoing discussion for a live forum.
I've no doubt, BAS, that you're well intentioned, and that you're quite the gifted amateur with a good deal of (non-practical) knowlege. But I've found in the past that you've had an unrealistic expectation - and a certain contempt for other DIYers.
The answer is not to put the thumbscrews on would-be electricians by such interrogation, but to steer them through the particular task of the moment, whether it be a CU change or a simple light switch problem - in order that they do the work properly without putting anyone at risk.
This can only be achieved 'live' - and not by some great tome lost in the 'sticky' section..........
Yes of course, I'd be happy to deal with your retorts. Fire away.......
Best wishes,
Lucia x
this is no more unrealistic than putting two way wiring diagrams in the wiki or stiki and expecting people to go look at it...
it would give us something to steer people towards when they ask "how easy is it to do a board change?"..
these people quite often don't realise what's involved to do it safely and immediately accuse us of being a "boys only" club when we say it's very hard for a DIYer and that they would be best off getting a sparky in to do it...
it's not like we're offering an online electrical installation course here...
for changing a light switch there isn't really a vast deal of knowledge required and filling in gaps is easy, but for a more complicated and dangerous undertaking like a CU change then the required knowledge is substantially more..
so instead of just repeating the same words over and over again we can point them at the proposed wiki / sticki and tell them if they can answer the majority of them with confidence then we can help fill in gaps in their knowledge..
it would give us something to steer people towards when they ask "how easy is it to do a board change?"..
these people quite often don't realise what's involved to do it safely and immediately accuse us of being a "boys only" club when we say it's very hard for a DIYer and that they would be best off getting a sparky in to do it...
it's not like we're offering an online electrical installation course here...
for changing a light switch there isn't really a vast deal of knowledge required and filling in gaps is easy, but for a more complicated and dangerous undertaking like a CU change then the required knowledge is substantially more..
so instead of just repeating the same words over and over again we can point them at the proposed wiki / sticki and tell them if they can answer the majority of them with confidence then we can help fill in gaps in their knowledge..
OK here goes
My consumer unit had no RCD, was half hanging off the wall and had old type fuses that had fuses inside the fuse rather than fuse wire, and a separate very old fashion fuse for the immersion heater (with modern wiring).
The house has been rewired at some point as there's old black cable that disintegrates when you touch it that isn't connected anywhere, and grey cables that are obviously the replacement.
I've checked behind all the sockets, all connections are fine. I've checked inside the junction boxes I've found for the lighting circuits, all were fine except for one, which has the earth wire twisted together over the outside of the junction box, I've since done it properly.
I've had the earth tested and it's fine etc etc etc.
At the end of the day a ring circuit is a pretty simple thing. Wire comes out of fuse/cu, into socket, out of socket into next socket etc etc and back into the fuse/cu. It's not rocket science. OK there's places you shouldn't fix a socket, you need to make sure you route the cables safely etc but providing you follow this stuff, any half competent diyer should be able to do it very very easily.
I cut the seal on the main fuse and removed it. I then replaced the CU myself and it was no more complicated than wiring a plug except on a much bigger scale. Electric company came out to change my meter, didn't bat an eyelid at the missing seal, simply fitted a new one before they left.
You can argue until your blue in the teeth that I should have got an expert in, but the fact of the matter is, the new CU is a lot better than the old one. I now have everything labelled up nicely and RCD protection.
I have also run a separate ring main to the kitchen.
I have two part P qualified friends, both these guys say that Part P is a money making scheme brought in to scare people off of DIY. Both say it actually does nothing except make a load of money for various people, because the average diyer will do it regardless, the unscrupulous trader simply wont care, and the people that do care and do do a good job, will have done so without Part P being there.
A friend is having an extension built. The local authority/building regs guy who came to discuss his building said words to the effect of the following
"We're now recommending people to use non part P certified people and getting the work inspected and certified at completion, there's been too many cases of Part P people self certification shoddy work which isn't being discovered until months later" His words not mine.
I appreciate there's cases of stupidity out there but part P (or any other regulation) will not stop the stupid people.
There are also a lot of very very competent DIYers out there who while might not do as neat job as a fully qualified spark/plumber/plasterer with years of experience etc, they often do a much better job than a lot of the properly certified but inexperienced legal tradesman out there.
If I'm doing work on my house, somewhere where I intend to live for many many years, I want to do the best, neatest, safest and professional job I possibly can.
The systems gone so far over the top that I (and many many many others, infact everyone I know) now just totally ignore getting approval for anything. When I'm supposed to get someone out and test my bathroom light because I've moved it something like 3" further away from the bath (a job that took literally 10 mins) things have gone too far.
The thing is, it's getting to a silly level now. You need to pay someone to come out and inspect your work whatever you do. I recently had Anglian windows fitted. I was going to do it myself, but at the time was a bit harassed. They're FENSA registered. If I'd have done it I'd have to pay for someone to come out and inspect my work. Their work was appalling. I would have done a 10 times better job.
I appreciate there's highly skilled and highly trained sparks on here and I mean absolutely no disrespect. I'm extremely well trained in computers, but I bet you don't call up a computer specialist every time something goes wrong with your PC. Or for that matter do you call out a plumber to change a washer/tap etc.
Personally I think there should be a simple DIY competence test that costs around the £50 - £100 mark. If you pass, then your free to do diy on your own property.
My consumer unit had no RCD, was half hanging off the wall and had old type fuses that had fuses inside the fuse rather than fuse wire, and a separate very old fashion fuse for the immersion heater (with modern wiring).
The house has been rewired at some point as there's old black cable that disintegrates when you touch it that isn't connected anywhere, and grey cables that are obviously the replacement.
I've checked behind all the sockets, all connections are fine. I've checked inside the junction boxes I've found for the lighting circuits, all were fine except for one, which has the earth wire twisted together over the outside of the junction box, I've since done it properly.
I've had the earth tested and it's fine etc etc etc.
At the end of the day a ring circuit is a pretty simple thing. Wire comes out of fuse/cu, into socket, out of socket into next socket etc etc and back into the fuse/cu. It's not rocket science. OK there's places you shouldn't fix a socket, you need to make sure you route the cables safely etc but providing you follow this stuff, any half competent diyer should be able to do it very very easily.
I cut the seal on the main fuse and removed it. I then replaced the CU myself and it was no more complicated than wiring a plug except on a much bigger scale. Electric company came out to change my meter, didn't bat an eyelid at the missing seal, simply fitted a new one before they left.
You can argue until your blue in the teeth that I should have got an expert in, but the fact of the matter is, the new CU is a lot better than the old one. I now have everything labelled up nicely and RCD protection.
I have also run a separate ring main to the kitchen.
I have two part P qualified friends, both these guys say that Part P is a money making scheme brought in to scare people off of DIY. Both say it actually does nothing except make a load of money for various people, because the average diyer will do it regardless, the unscrupulous trader simply wont care, and the people that do care and do do a good job, will have done so without Part P being there.
A friend is having an extension built. The local authority/building regs guy who came to discuss his building said words to the effect of the following
"We're now recommending people to use non part P certified people and getting the work inspected and certified at completion, there's been too many cases of Part P people self certification shoddy work which isn't being discovered until months later" His words not mine.
I appreciate there's cases of stupidity out there but part P (or any other regulation) will not stop the stupid people.
There are also a lot of very very competent DIYers out there who while might not do as neat job as a fully qualified spark/plumber/plasterer with years of experience etc, they often do a much better job than a lot of the properly certified but inexperienced legal tradesman out there.
If I'm doing work on my house, somewhere where I intend to live for many many years, I want to do the best, neatest, safest and professional job I possibly can.
The systems gone so far over the top that I (and many many many others, infact everyone I know) now just totally ignore getting approval for anything. When I'm supposed to get someone out and test my bathroom light because I've moved it something like 3" further away from the bath (a job that took literally 10 mins) things have gone too far.
The thing is, it's getting to a silly level now. You need to pay someone to come out and inspect your work whatever you do. I recently had Anglian windows fitted. I was going to do it myself, but at the time was a bit harassed. They're FENSA registered. If I'd have done it I'd have to pay for someone to come out and inspect my work. Their work was appalling. I would have done a 10 times better job.
I appreciate there's highly skilled and highly trained sparks on here and I mean absolutely no disrespect. I'm extremely well trained in computers, but I bet you don't call up a computer specialist every time something goes wrong with your PC. Or for that matter do you call out a plumber to change a washer/tap etc.
Personally I think there should be a simple DIY competence test that costs around the £50 - £100 mark. If you pass, then your free to do diy on your own property.
What were the test results for your RCDs?
So you'd do away with all the sticky topics and the Wiki, would you, and answer each question from scratch, post diagrams afresh each time they were required?
I don't think it even slightly unrealistic to expect people to be prepared to learn how to do things properly, and the only ones I feel contempt for are those who refuse to learn and are stupid enough to think it'll be OK to attempt jobs knowing that they are incompetent.
There's no shame in being ignorant and incompetent - I am both of those regarding brain surgery, for example. About all I know is where the brain is, but I'm not stupid enough to think that that'd be enough to make it OK for me to have a go at brain surgery.
But some people think that because they know where their hall/landing light switch is.....
You cannot steer people through major jobs like rewires and CU replacements via a Q&A session. The whole point of the questions is not to put thumbscrews on people but to try and present a genuine picture of all the things that are involved in doing it properly.
The problem with trying to steer people through the task of rewiring a house is that it would be a desperately inefficient and appallingly structured way to impart all of the knowledge they'd need to acquire.
And doing it by simply answering their questions would be even worse, as they'll only ask about things they realise they need to find out about.
Donald Rumsfeld has done many things worthy of condemnation, but I never understood why he was so ridiculed when he pointed out, quite correctly, that there really is a difference between known unknowns and unknown unknowns.
People will only ask about the former, so if they have, for example, no idea whatsoever that there are rules on where cables can be concealed then they won't think to ask or look it up.
We all know that they likewise won't look at the Wiki etc before asking questions, but that type of resource is also of value when people can be pointed at it and told that they'll find the answer to their question there.
Pjo - the only reason you think that replacing your CU was "no more complicated than wiring a plug except on a much bigger scale" is precisely because of your unknown unknowns.
Maybe the new one was better than what was there before, but that's not the point - you don't know if it is good enough, but by doing the work you took on a legal responsibility to ensure that it was good enough, not just better.
Say you had an unroadworthy car, and you carried out ineffective repairs to it. It might well end up better.
But it would still be unroadworthy.
As RF pointed out, you don't know if your RCDs work properly.
You also don't know if you have proper continuity on your ring final cables, you don't know if your main bonding is OK, you don't know if your fault-loop values are low enough for your MCBs to operate properly, you don't know if the insulation of the cables is all OK, you don't know if the polarity of your installation is correct...
If you want to do the best, neatest, safest and professional job you possibly can then you do need to learn and come to understand why all of the things mentioned in this topic are important.
Maybe the new one was better than what was there before, but that's not the point - you don't know if it is good enough, but by doing the work you took on a legal responsibility to ensure that it was good enough, not just better.
Say you had an unroadworthy car, and you carried out ineffective repairs to it. It might well end up better.
But it would still be unroadworthy.
As RF pointed out, you don't know if your RCDs work properly.
You also don't know if you have proper continuity on your ring final cables, you don't know if your main bonding is OK, you don't know if your fault-loop values are low enough for your MCBs to operate properly, you don't know if the insulation of the cables is all OK, you don't know if the polarity of your installation is correct...
If you want to do the best, neatest, safest and professional job you possibly can then you do need to learn and come to understand why all of the things mentioned in this topic are important.
And may I say how flattered I am that you took the trouble to register just to give your opinion of me.
I'm sure we all value it greatly, and look forward with eager anticipation to more valuable contributions from you.
And may I say how flattered I am that you took the trouble to register just to give your opinion of me.
I'm sure we all value it greatly, and look forward with eager anticipation to more valuable contributions from you.
I agree, what a killer first post. Going to many BBQ's this summer?
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