Minor Works Certificate for DIY’ers.

[JohnW2]

It is a desirable goal. What is undesirable is the route to it being "let's encourage the OP to do things he doesn't understand".

Sure, but the reality is that most of them don't need any 'encouragement'. I'm sure that very few come here to find out whether or not they should do a particular piece of DIY work. Most will already have decided that they are going to do it (indeed, they have often started doing it) (and will do it regardless of what is said here), but seek advice how to do so as 'properly' or safely as is practical.

Kind Regards, John

 

[scousespark]

I don't really get where Eric is coming from. Why should we look for ways to make it easy for people to 'sort of comply' with BS7671? The common comparison is with driving. This is like saying there should be an easier test for people who are only going to drive on Sundays and only when it's dry and sunny. I have no issue with DIY, but I don't see why the test regime should be watered down.

 

[JohnW2]

I don't really get where Eric is coming from. Why should we look for ways to make it easy for people to 'sort of comply' with BS7671? The common comparison is with driving. This is like saying there should be an easier test for people who are only going to drive on Sundays and only when it's dry and sunny. I have no issue with DIY, but I don't see why the test regime should be watered down.

Good to see you! I agree with you in concept, but I suppose eric is trying to be realistic/pragmatic. He is acknowledging the fact that, whether we like it or not and whether it is ideal or not, widespread DIY not including a 'full scale test regime' (probably not including any tests at all in a high proportion of cases) is going to continue, and has the (I would say honourable) motive of trying to help them to do that more safely than would be the case without his proposed 'assistance'.

I personally don't see that his ideas are workable, or would even be taken notice of by a significant proportion of DIYers. Apart from anything else, as you say, it would be effectively giving blessing to something which was less than full compliance with BS7671. Whilst any of us who is realistic must acknowledge that such is almost the norm (at least in terms of testing) for electrical DIY, 'acknowledging' is very different from condoning or facilitating! In a sense it's a pity - if we 'could' say it, to get a significant proportion of DIYers to heed advice to "at least do (easy/cheap) tests X, Y & Z, even though that would not be enough to satisfy BS7671)", that would presumably enhance safety of electrical DIY work to at least some extent.

Kind Regards, John
Edit: crucial missing word added!

 

[riveralt]

This is like saying there should be an easier test for people who are only going to drive on Sundays and only when it's dry and sunny

Have you driven around Liverpool recently on a Sunday - mayhem - scary - never seen so many cloth caps and glasses both male and female peering over the steering wheel. You take your live in your own hands if you take such a risk. There is no harder test..

 

[TonyW2]

In a sense it's a pity - if we 'could' say it, to get a significant proportion of DIYers to heed advice to "at least do (easy/cheap) tests X, Y & Z, even though that would be enough to satisfy BS7671)",

[/QUOTE]
Missing "not"

Could we not have a sticky that lists the full and correct tests that should be done to comply with BS767, including how to conduct those tests and what equipment would be needed, arranged in an order of likely risk? The DIYer could then make a better informed decision as to which they would chose to undertake.

 

[JohnW2]

In a sense it's a pity - if we 'could' say it, to get a significant proportion of DIYers to heed advice to "at least do (easy/cheap) tests X, Y & Z, even though that would be enough to satisfy BS7671)", ...

Missing "not"

. Whoops - apologies. Post has been corrected!

Could we not have a sticky that lists the full and correct tests that should be done to comply with BS767, including how to conduct those tests and what equipment would be needed, arranged in an order of likely risk?

We could, but, per scousespark's concerns, even "...arranged in an order of likely risk..." (if it said that) could be taken as at least suggesting, if not condoning, the possibility of undertaking less than the full set of tests. It would also be an 'interesting' exercise, probably with differing opinions, deciding what that order should be! ....

The DIYer could then make a better informed decision as to which they would chose to undertake.

They could but, quite honestly, I doubt that it would actually make a lot of difference to what testing 'occasional DIYers' did, or did not, undertake. I could, of course, be wrong.

Kind Regards, John

 

[ban-all-sheds]

Sure, but the reality is that most of them don't need any 'encouragement'.

They don't - they need discouragement.

I'm sure that very few come here to find out whether or not they should do a particular piece of DIY work.

That may not be what they were expecting to find, but it is what they should find.

Most will already have decided that they are going to do it (indeed, they have often started doing it)

Then they need to be corrected.

(and will do it regardless of what is said here), but seek advice how to do so as 'properly' or safely as is practical.

The problem is that you almost always refuse to have anything to do with the fact that they way to do it as properly and/or as safely as is practical is to not DIY.

 

[JohnW2]

The problem is that you almost always refuse to have anything to do with the fact that they way to do it as properly and/or as safely as is practical is to not DIY.

That is probably usually true, although we know that there are some so-called 'electricians' who do things less "properly and/or safely" than some DIYers, so "not DIYing" is not a panacea.

However, it's a pretty extraordinary statement to find being made in a DIY forum - unless your belief is that the name of "DIYnot" indicates that it intended as a place where people come to be told not to do electrical DIY.

Kind Regards, John

 

[ban-all-sheds]

However, it's a pretty extraordinary statement to find being made in a DIY forum - unless your belief is that the name of "DIYnot" indicates that it intended as a place where people come to be told not to do electrical DIY.

That you refuse to have anything to do with the idea that people should be encouraged to develop competence does not mean that it's not a good one.

 

[JohnW2]

Late on weekend nights can be quite a fun place around here

 

[ericmark]

I re-looked at the MWC and it is clearly not the only testing required.

We may not write it down but before we get out a single tool we start the inspecting and testing. Working out if RCD protected and what size of over current device is fitted and existing cables sizes and more to the point current carrying capacity all has to be completed before we even start on the job of adding to the circuit.

Because we know we often don't look at Wiki and Electrics Inspection and testing we or at least I assumed it was all there and the DIY guy was just too lazy to read.

* electrics:Instruments Does not exist.
* Order of Tests Seems to be some confusion here not really going to help the DIY guy.


* electrics:Continuity Testing Does not exist.
* electrics:Ring Final Circuit Testing Does not exist.
* electrics:Insulation Testing Does not exist.
* electricsolarity Testing Does not exist.
* Electrics:Loop Testing Links to two forum pages.
* electrics:Earth Electrode Testing Does not exist.
* electrics:RCD Testing Does not exist.

* Electrics:Certification Simply explains there are three forms no reference to completion or compliance certificates.

So there is at this time very little to help the DIY guy. Even saying how continuity testing needs at least 250 mA or Insulation testing is normally 500 volt but in some special situations we do use 250 volt and a standard multi-meter will not do this seems to have been missed.

Wording is everything and if one starts off with a statement that the test gear required is expensive and it is realised many DIY people will not buy this expensive equipment. So after DIY work is completed arrangements are required for some one with the equipment to come and inspect and test and issue an EICR.

However while waiting for the full tests to be completed doing some basic inspection and testing will minimise the risk until proper tests are completed.

So taking for example "Ring Final Circuit Testing" what do we say?

Personally I feel tests should include working out how the ring is fed and so being able to know if RCD protected already. As to if testing for dead should include any advice on problems with borrowed neutrals I am not sure. Neither am I sure about working inside the consumer unit. With a loop impedance tester we can test and record open up a socket and test ring continuity and if intact we then know the likely loop impedance when completed so when re-doing the loop impedance test at the end we are reasonable sure with suitable readings no wire has become disconnected. However without the loop tester the only sure way is to test where we are not moving any cables after the test which can't be seen. So only place where we can do that is the consumer unit. However in most cases there is no ability to isolate elsewhere without drawing the DNO fuse. I am certainly not happy telling any DIY person to go into a consumer unit which may have missing internal guards.

Every lecturer has the option to ask questions and this allows him to test if what he said has been understood. But a Wiki entry has no feed back. I feel as a result the information does have to be general. To say test to see where the socket is supplied from and isolate is OK, but say plug in your table lamp and switch it one then go to the consumer unit and switch off each MCB is turn leaves too many options not covered. Main point is houses wired before 1990 do not have consumer units.

If we say there should not be any DIY then may as well close the site. But to argue between our selves about what information should be given is also not helpful for the DIY person.

 

[JohnW2]

If we say there should not be any DIY then may as well close the site. But to argue between our selves about what information should be given is also not helpful for the DIY person.

If there are differing opinions about what information should be given to DIYers, what alternative is there to discussing ('arguing about') the issue - just going with one person's view (maybe yours)?

Kind Regards, John

 

[ericmark]

OK point taken. We do need to discuss the only way that's not required is to say nothing except quoting from the book.
Calculating Zs (forum Link)
It seems anything but calculating Zs all that is talked about is what B, C, and D mean on a MCB. It is an interesting point as in the main I measure Zs and use that to work out other values but there is nothing to stop one measuring the length of a cable, Take Ze from the DNO by enquiry, Add correction factor etc and from say Ze of 0.35Ω and 106 meters of cable of 2.5mm installation method 101 arranged as a ring with ambient temperature of 30°C with Cg and Ca as unity work out that Zs will be 0.94Ω.

You also need the Tabulated mV/A/m and a calculator able to find square roots. I personally would not like to work it out too often without a pre-written program. And is there really any need? We know the limit is 106 meters of 2.5mm² cable with a 32A final ring so why would on want to calculate Zs?

As to calculating R1 + R2 "whats the method used to calculate R1+R2 from r1 rn r2 readings on a ring final?" was the question. R1 + R2 divided 4 was simple answer but no explanation as to why divided by 4 so easy to say because a ring and looking a centre point one it's only gone half way around and two you have doubled up on the cable but the answer was you should know why.

OK there was one who did start to explain how to work it out from a single measurement but he's not been seen since 2008. So all in all it would seem we no longer have a Wiki.

 

[EFLImpudence]

As to calculating R1 + R2 "whats the method used to calculate R1+R2 from r1 rn r2 readings on a ring final?" was the question.
R1 + R2 divided 4 was simple answer

Or - wrong answer.

Just in case someone isn't sure.

 

[JohnW2]

.... there is nothing to stop one measuring the length of a cable, Take Ze from the DNO by enquiry, Add correction factor etc and from say Ze of 0.35Ω and 106 meters of cable of 2.5mm installation method 101 arranged as a ring with ambient temperature of 30°C with Cg and Ca as unity work out that Zs will be 0.94Ω.

... but that theoretical calculation is telling you what the Zs should be. The whole point of testing is surely to ascertain what the Zs of the circuit actually is, isn't it? Your calculation would obviously mean nothing if, say, the CPC were not properly connected at the CU!

Kind Regards, John