Queries regarding Inspection Report I've just had completed

[Risteard]

I would therefore draw from the IET statement that a complete suite of tests (dead and live) should be done in a domestic situation unless there is good cause not to do so )or for some reason it has been agreed with the customer not to do something?

Only if you ignore the statement in GN3 that cpc continuity can be verified through live loop testing. Dead testing for cpc continuity is designed to ensure that the installation is not energised with unearthed parts. This caution is no longer necessary when the installation is already energised, as any potential danger already exists.

Dead testing may be useful for ensuring that exposed conductive parts are earthed where it is difficult to disconnect these for Zs testing. In this instance it would be R2 testing and not R1+R2 testing. (Think of a heavy chandelier or whatever.)

 

[SparkyChick]

Just to explain. I gave you a 'disagree' about this post. It's nothing personal (honestly) but how anyone can maintain a viable business at those sort of rates I really dont know.

In this part of the world I'm considered to be middle of the road on pricing as far as I can tell.

I don't do many EICRs because normally it's a full day around the £240 mark. Most people are getting them in 2/3 hours for £80-£120. I can't compete with that because I like to be thorough so I can sleep at night.

In this case it's a bit of a favour for a forum member who needed one quick, so I figure karma will pay me back at some point in the future

 

[Darkwood]

What dead tests would you carry out during periodic inspection and testing? Insulation resistance is the only one I would do (assuming that the installation could be de-energised for the test) and would not be with individual circuits but the installation in parallel as required by BS7671. I don't see any reason to be disturbing connections in the DB - although I would be checking tightness of terminals.

Correcting any defects is not the purpose of periodic inspection and testing and is not something I would do. It would be quoted separately as a completely separate job.

Firstly I was commenting in the context of the thread 'domestic' so I have very rarely ever seen a reason not do a full compliment of tests, I would though agree that commercial and industrial can be somewhat of a challenge if they are a mess and this would impact on testing time thus I would discuss with the customer but domestic is seriously not going to be a big issue of putting the cores back in the correct order once you have tested.

How would you ensure without removing cpc from its terminal that one is not picking up parallel paths?, when doing R2 or R1+R2, you are ensuring that the earthing for that particular circuit is not broken, damaged or high resistance etc, measuring ELI when energised only proves an earth path exists but it doesn't confirm the integrity or the circuit earth itself, think boiler supply where an earth path may be present through the pipework itself even if the boiler supply earth was broken.

 

[ipf]

Putting this to bed now guys...thanks for all your assistance and help with my queries, you have been complete pros even essex and buzz who took time out to patronise me , all the best.

Patronise, eh?.
People seem to jump to conclusions an awful lot. I like to see things from all sides before offering advice on an issue of which I don't personally know all the ins and outs.
There could be much more involved, from both sides. Things look a bit iffy from the contractor's side with the info put forward but the full facts are not known. We are receiving info from a source unknown to us...info which indicates the OP carrying out electrical installation and/or alterations to his own property. Is he competent to carry out this work? Well, it seems not if no initial certificate was produced. He mentions family safety, following the EICR....what about prior to it, following the work carried out?
I am not jumping to conclusions... I've seen plenty 'being led down the wrong path' following such 'leaping'.
By the way, I don't see what trades persons being 'complete pros' has to do with offering free advice.

 

[Risteard]

How would you ensure without removing cpc from its terminal that one is not picking up parallel paths?

Certainly there may be parallel paths. However you should remember that you are specifically advised not to unnecessarily dismantle and reassemble the installation as this is more likely to introduce faults than to find them. I would state with absolute confidence that (R1+R2) testing is almost always wholly inappropriate for periodic inspection and testing. (It can be useful if there is no supply - e.g. Economy 7 or a de-energised installation or whatever.)

 

[Darkwood]

Certainly there may be parallel paths. However you should remember that you are specifically advised not to unnecessarily dismantle and reassemble the installation as this is more likely to introduce faults than to find them. I would state with absolute confidence that (R1+R2) testing is almost always wholly inappropriate for periodic inspection and testing. (It can be useful if there is no supply - e.g. Economy 7 or a de-energised installation or whatever.)

I find it strange that you consider dropping a wire out of a terminal as unnecessarily dismantling the installation, I would consider lifting floorboards up etc is what this little area is covering, otherwise as I have expressed already, how can you ensure the integrity of the earth of a circuit when you can get a false positive through parallel paths, I will agree in certain situations it may be warranted that limitations exists to doing a test but these are the exemptions not the rule.
I was taught to do a full set of tests to ensure the integrity of a circuit and this requires both energised and dead tests for the very reason I have raised about ensuring the integrity of the earth itself and you don't get a false positive, as far as I am aware all the testing guides and advice out there recommends the complete set of tests where possible, I think you are misinterpreting the part about unnecessarily dismantling, unless it has drastically changed then it did once mean pulling the infrastructure and/or fitted furniture apart just to access a joint to give one of many examples... I cannot ever see this applies to removing an Earth or a Neutral from its terminal block, that isn't exactly what I call dismantling the installation.

I will add when you carry out a test and inspection you are assessing the installation and the safety of it, this cannot be done if you do not do the full scope of tests for the reasons given, if you test a shower and the earth is not connected yet your ELI give a pass through a parallel path then you have not identified a very dangerous situation, that is the whole point of the testing and inspection, how can you justify omitting dead tests when you may miss a very real danger, in the scope of this thread which is domestic based then I cannot ever see a real reason to shun dead testing, I have not yet come across a situation where power cannot be removed to do so, commercial and industrial is a different ball park but still it should always be done unless their are exceptional circumstances where power cannot be removed, IE Hospitals IC wards etc...

 

[Risteard]

I find it strange that you consider dropping a wire out of a terminal as unnecessarily dismantling the installation

That's precisely what it relates to.

Also (R1+R2) testing will not prevent parallel paths from giving you a reading, e.g. in the case of supplementary bonding.

 

[richy3333]

Only if you ignore the statement in GN3 that cpc continuity can be verified through live loop testing. Dead testing for cpc continuity is designed to ensure that the installation is not energised with unearthed parts. This caution is no longer necessary when the installation is already energised, as any potential danger already exists.

Dead testing may be useful for ensuring that exposed conductive parts are earthed where it is difficult to disconnect these for Zs testing. In this instance it would be R2 testing and not R1+R2 testing. (Think of a heavy chandelier or whatever.)

Sorry but we will have to agree to disagree. Your 'quote' comes after that which I stated and is merely a note as part of table 3.4. Table 3.4 states under Ring circuit continuity 'Where there are records of previous test, this test may not be necessary unless there may have been changes made to the ring final circuit'. Why do the GN's then say this if continuity on final circuits is NOT required - as you argue?

I mean no disrespect to you but in my own opinion anyone walking around simply doing Zs testing on final circuits when continuity readings can be taken is only doing half a job unless that is what has been agreed with the customer and the customer fully understands what they are agreeing to with such limitations. The analogy I see is that my garage doesn't just start my van engine and then slap an MOT pass on the vehicle?

 

[richy3333]

In this part of the world I'm considered to be middle of the road on pricing as far as I can tell.

I don't do many EICRs because normally it's a full day around the £240 mark. Most people are getting them in 2/3 hours for £80-£120. I can't compete with that because I like to be thorough so I can sleep at night.

In this case it's a bit of a favour for a forum member who needed one quick, so I figure karma will pay me back at some point in the future

Thanks for the explanation. Karma restored with a 'like'

 

[Risteard]

Sorry but we will have to agree to disagree. Your 'quote' comes after that which I stated and is merely a note as part of table 3.4. Table 3.4 states under Ring circuit continuity 'Where there are records of previous test, this test may not be necessary unless there may have been changes made to the ring final circuit'. Why do the GN's then say this if continuity on final circuits is NOT required - as you argue?

I mean no disrespect to you but in my own opinion anyone walking around simply doing Zs testing on final circuits when continuity readings can be taken is only doing half a job unless that is what has been agreed with the customer and the customer fully understands what they are agreeing to with such limitations. The analogy I see is that my garage doesn't just start my van engine and then slap an MOT pass on the vehicle?

I never once mentioned ring final circuit continuity testing. That's not what was being discussed.

However, as you allude to, the Guidance states that where records exist and changes have not been made then it can be omitted.

Personally I would prefer to do end-to-end continuity for ring final circuits to have some indication of continuity - but this would almost always be at a socket outlet rather than ripping a DB apart. I wouldn't be doing the whole figure-of-eight thing without good reason (e.g. if there was particular reason to doubt the ring). If I was going to go to those lengths I would also be looking for additional remuneration.

It really ought to be remembered that we are not "testing" - we are carrying out inspection and testing. Inspection is listed first as it is the most important element of this. The testing is merely to supplement the inspection.

Many things can pass tests which can be seen to be unacceptable and/or unsafe by inspection.

 

[Darkwood]

That's precisely what it relates to.

Also (R1+R2) testing will not prevent parallel paths from giving you a reading, e.g. in the case of supplementary bonding.

Please cite where it even suggests disconnecting a wire in a dist' board is classed as 'unnecessarily' dismantling the installation, I honestly find this bizarre,it is necessary to do to do the tests, we are taught this method, even if you take a modern testing course now you do all the tests in the usual order, when you did you AM2 test and inspection module would you have failed if you did not do the dead tests as part of the testing routine, I dare say yes, telling the examiner the live test will suffice would be an interesting concept to see what response you got.

In answer to your other point, I take the wire out of the board for dead tests, I will also in the example of a shower, drop the wire out of the shower, this proves the integrity of the cable and the earth wire itself with no parallel paths, I will agree somewhat that commercial and industrial may have circumstances where parallel paths cannot be omitted for testing in all cases but we are on about domestic.

I am open to other views here and will stand corrected if things have changed and I missed that bus but how can one test the actual circuit earthing if you cannot eliminate false positives from energised testing, you simply cannot so you could potentially mark a circuit as safe when it is a dangerous to use, even if your definition of unnecessarily dismantling of the installation was correct, can you not as a professional electrician see the clear danger in this approach that circuits could be unsafe and passed as safe?

 

[Risteard]

Please cite where it even suggests disconnecting a wire in a dist' board is classed as 'unnecessarily' dismantling the installation, I honestly find this bizarre,it is necessary to do to do the tests, we are taught this method, even if you take a modern testing course now you do all the tests in the usual order, when you did you AM2 test and inspection module would you have failed if you did not do the dead tests as part of the testing routine, I dare say yes, telling the examiner the live test will suffice would be an interesting concept to see what response you got.

In answer to your other point, I take the wire out of the board for dead tests, I will also in the example of a shower, drop the wire out of the shower, this proves the integrity of the cable and the earth wire itself with no parallel paths, I will agree somewhat that commercial and industrial may have circumstances where parallel paths cannot be omitted for testing in all cases but we are on about domestic.

I am open to other views here and will stand corrected if things have changed and I missed that bus but how can one test the actual circuit earthing if you cannot eliminate false positives from energised testing, you simply cannot so you could potentially mark a circuit as safe when it is a dangerous to use, even if your definition of unnecessarily dismantling of the installation was correct, can you not as a professional electrician see the clear danger in this approach that circuits could be unsafe and passed as safe?

An exam situation is not relevant as they are trying to determine that you know how to conduct all of these tests. That does not mean that they are sensible or advisable when carrying out periodic inspection and testing. This is exactly the over-reliance on testing that I am referring to. An inspection of all the senses is the key part, supplemented by relevant tests as appropriate.

Initial verification and periodic inspection are very, very different beasts. We are not trying to determine whether an installation is safe and compliant to energise as the installation is already energised. What we are concerned with is whether the installation is satisfactory to remain in service.

Totally different thing. Frankly if anyone told me that they did (R1+R2) testing during periodic inspections, my immediate thought would be that they have very little experience of periodic inspection and testing.

 

[buzzlightyear]

the only way of do dead testing ,is when their is no supply to energised too...but the inspector knowing that the supply to that consumer unit was live .I would love to see the test values .

 

[Darkwood]

An exam situation is not relevant as they are trying to determine that you know how to conduct all of these tests.

You make a relevant point that I cannot argue with.

Initial verification and periodic inspection are very, very different beasts. We are not trying to determine whether an installation is safe and compliant to energise as the installation is already energised.

I agree.

What we are concerned with is whether the installation is satisfactory to remain in service.

You still haven't addressed or replied to my main point, how can one determine whether an installation is satisfactory to remain in service when simply doing a energised test to establish a acceptable earth reading could be masking a dangerous circuit if not confirmed with a (R1+R2)
I will also add that doing the R1 +R2 on a socket ring and checking readings at each socket can establish where multiple spurs exist on one spur leg that in itself could be a fire risk, this cannot be determined by energised testing.

Frankly if anyone told me that they did (R1+R2) testing during periodic inspections, my immediate thought would be that they have very little experience of periodic inspection and testing.

I see this at the moment as opinion only, you haven't cited anything to back your position up, also you suggest anyone doing so you make you think they were of little experience, maybe they have been taught differently or are with companies with very different views or methods, I am no longer in a scheme myself as I don't do that kind of work enough anymore, I do however get in a well established local testing company sometimes for the factories that I am on call to to do there Periodic's, they do the dead tests as part of their routine, are you saying they are wrong and inexperienced?

 

[Risteard]

What they need to ask themselves is whether they are conducting a test simply because there is a box in which to record a result, or whether they are conducting it for some useful purpose.

In relation to your other point I actually answered it already. I pointed out that (R1+R2) testing is no less at risk of parallel paths than Zs testing.