TT eicr code?

[Des 56]

Thank goodness for 2 voices of reason in the last 2 posts in this thread

My last post as well on the subject
The arguments have been presented and in my opinion, it is not and never has been in any doubt from the onset

A compliant 16th edition installation should not be considered potentially dangerous just because the date on the calender has changed

 

[D Skelton]

OK, let's add a bit of perspective here, as things are seldom black and white.

A fully complaint 16th ed install although not meeting 17th regs, how can you say it is potentially dangerous ? which is what a C2 is.

Because the regs say so! It really is that simple

BS7617:2011 621.2 states; "Periodic inspection comprising a detailed examination of the installation shall be carried out . . . to show that the requirements for disconnection times . . . are complied with to provide for the safety of persons and livestock".

As I said in an earlier post, that says to me that if disconnection times are not met then the safety of persons and livestock is not provided for, thus making the installation unsafe. A C2, according to the regulations, is the only code that can be given.

 

[spark 68]

D I really have said enough on here already, lol

last post from me (unless I get dragged in again) lol

sigh, 621.1 where required, periodic inspection and testing of every electrical installation shall be carried in accordance with 621.2 to 5 (which includes the bit you have posted above), in order to determine so far as reasonably practicable, whether the installation is in a satisfactory condition for continued service.

it goes on to say, wherever possible the documentation arising from the initial certification and any previous periodic I&T shall be taken into account (yeah right lol).

Where no previous documentation is available, investigation of the electrical installation shall be carried out prior to carrying out the PIR.

Now what investigation do you think they mean prior to carrying out the PIR ? after all the PIR is an investigation in itself, could it be to determine what edition it is maybe ?

Why would you expect an earlier editions disconnection times to comply with a later editions, when you know for a fact that the later editions were shortened ?

In the absence of prior paperwork for a known earlier edition, then I would look to the earlier standards to determine what was acceptable then, this is the beginning of my investigation prior to the PIR.

And on the off chance that an original EIC existed (lol) , and your current test results happened to reasonably match it, then what ? after all we are only looking for significant detioriation.

 

[Engineer54]

Because the regs say so! It really is that simple

BS7617:2011 621.2 states; "Periodic inspection comprising a detailed examination of the installation shall be carried out . . . to show that the requirements for disconnection times . . . are complied with to provide for the safety of persons and livestock".

As I said in an earlier post, that says to me that if disconnection times are not met then the safety of persons and livestock is not provided for, thus making the installation unsafe. A C2, according to the regulations, is the only code that can be given.

As i pointed out before, what detailed examination is going to distingquish between a trip time of 0.4 and 0.2 sec, when an RCD device is the main source of earth fault protection?? Same goes for a L-N fault protected by a MCB.

 

[D Skelton]

As i pointed out before, what detailed examination is going to distingquish between a trip time of 0.4 and 0.2 sec, when an RCD device is the main source of earth fault protection?? Same goes for a L-N fault protected by a MCB.

I'd examine the supply characteristics, in detail lol. If TT then 0.2s maximum disconnection time for general circuits where an RCD is used for fault protection applies. If that maximum permitted disconnection time cannot be met, I'd C2 it.

I think we've all said our piece, and well I might add on both sides of the argument.

Talk about topics that split the forum! lol

 

[Badged01]

Do people really believe that the IET would produce a set of Regulations, that would place themselves in a position where they could face litigation for allowing unsafe installations?

The above is very true, but my slant is probably different to what the poster meant!

The IET will update the regs to cover their 'butts' and currently they will stand behind the disconnection times in the BGB as being 'safe' as far as is reasonable practicable to understand at present. Then presumably the 'new, disconnection times in the BYB when issued!!. (Otherwise why change the times?) They legally can't make any location be upgraded to the latest edition of the regs (which are recommendations not enforceable law), so cant be prosecuted if 'old' installations don't meet the current 'safe' requirements. Infact they don't know if the old installations don't actually meet the latest disconnection times as they have no visibility! (I'm not in the mind of the IET so don't know their thinking behind changes to the times but my own industrial work experience of upgrading processes, procedures and instructions/guidance has always been to make things better/safer not the other way around!!)

I guess their get out clause would be that "we discharge our duties by stating what is 'recommended' as being safe in the current regs and rely upon 'competent' inspectors conducting EICR's of old installations (when required by owners, not legally enforceable) to intepret our regs to ensure the disconnection time is safe and advise the owner accordingly". i.e. we've passed the buck down to the inspector to check if its safe when inspecting to our latest regs!

But ask yourself the question, should little Johnny get electrocuted and you have signed the EICR saying the 16th edn disconnection times are C3 and the installation is satisfactory for continued use, even when there is a more stringent disconnection time to be applied in the current regulations which your are conducting your EICR to and you know about - you're the competent inspector?. When the defence call the 'expert' witness from the IET, what disconnection time do you think he is going to stand behind as the recommended safe time? I dont think he will be saying any time from the 15th/16th edn or the IET could then be liable to litigation themselves in approving/recommending the 'unsafe' disconnection time which killed little Johnny! And if you know anything about big organisations, one thing they are very good at is covering their own butts and happily sacrificing the worker (inspector) if it suites their ends.

If nothing else cover your own butt and go "C2" -- the customer doesn't have to upgrade if he doesn't want to, you can't make him (same as the IET) but atleast you have advised him about the potential risk! If they want to argue further about the disconnection time being safe or not they can take that up with the IET, whose guidance on the subject you have followed

I'ver waffled on far too much and enough has been said on the post for the layman to choose his own position. So like the previous posts, this is my last post before agreeing to disagree with everyones interpretation of C3 and disgracefully bowing out with old age. The thread could go on and on and round and round otherwise ......

 

[Engineer54]

I'd examine the supply characteristics, in detail lol. If TT then 0.2s maximum disconnection time for general circuits where an RCD is used for fault protection applies. If that maximum permitted disconnection time cannot be met, I'd C2 it.

I think we've all said our piece, and well I might add on both sides of the argument.

Talk about topics that split the forum! lol

Tut, tut, tut, ...what i'm saying is, if the circuit or circuits are protected with an RCD device, it wouldn't matter a jot if it was 0.2 or 0.4 sec disconnection times!! You can examine the supply characteristics etc all you like, so long as the RCD device passes the standard tests, it's a good'un!!

Now if you want a topic that we DO disagree on. Check out this thread!! lol!!

http://www.electriciansforums.co.uk...rum/88682-eal-test-inspection.html#post919002

 

[D Skelton]

Tut, tut, tut, ...what i'm saying is, if the circuit or circuits are protected with an RCD device, it wouldn't matter a jot if it was 0.2 or 0.4 sec disconnection times!! You can examine the supply characteristics etc all you like, so long as the RCD device passes the standard tests, it's a good'un!!

Now if you want a topic that we DO disagree on. Check out this thread!! lol!!

http://www.electriciansforums.co.uk...rum/88682-eal-test-inspection.html#post919002

It would matter if the RCD in question wouldn't disconnect in the required time

 

[telectrix]

never seen a RCD that didn't meet the 0.2 secs @ x1. always get < 50mSec.( unless, of course it's faulty).

 

[spark 68]

Badged mate you have a 0.2 disconnection time as your reason for a C2, fair enough, but you are still wrong.

if you have a look in the current regs (BGB) at reg 411.3.2.2 under the table in that reg it points you to 411.3.1.2 and tells you that if protective equipotential bonding as per 411.3.1.2 is present (incoming water, gas etc.), then TN values (0.4s) for your disconnection time may be used for a TT system.

This is in the current regs, not the 16th, lol

In a fully compliant 16th ed install, 411.3.1.2 in the 17th, would be met anyway, and don't forget S/Os (and showers) would be covered by a 30mA device in the 16th too which would disconnect in 40ms @ 5Idn

Edit: OK the above applies to where an OCPD is used for disconnection, but further reading relating to RCDs as a means of fault protection in 411.5.3 states the disconnection time shall be either 411.3.2.2 or 411.3.2.4 and RA X Idn <=50

it then says the requirements of this regulation are met if the ELI of the circuits protected by RCD meet the values in table 41.5 in the BGB
, which they would do even in the 16th

 

[HappyHippyDad]

Well thank you Spin for that rather patronising lesson on how to conduct myself whilst inspecting and testing an electrical installation. It might help you to know that I'm well aware how to code something that is potentially dangerous!

I couldn't care less what previous regulations state, I am inspecting the installation to current regulations and a major part of that procedure means determining whether or not the installation complies with the requirements for ADS. An overcurrent protective device not disconnecting a circuit in the required time under fault conditions IS potentially dangerous, and saying so is not tantamount to fraud, nor does it indicate a lack of knowledge?!?!?!? What a load of twoddle!

To use the quote from the current regs; "This does not necessarily mean that they unsafe for continued use or require upgrading". There you have it fella. This means that it may not in all cases be unsafe, but in some cases it could be. That is what the use of the words 'does not necessarily' indicate. If the IET would never say that earlier editions of the regulations were 'unsafe', or at least 'less safe' than the current, there'd be no need for them to keep changing them would there?!




I have read it, and nowhere does it say that in all cases a bare live conductor must be insulated whether it is within reach or not.


Finally, I couldn't help but pick out this little gem! Talk about contradiction!

First Ed of the wiring Regs (1882): section 15: "All wires used for indoor purposes should be efficiently insulated. "

http://www.electriciansforums.co.uk...m/87573-first-edition-wiring-regs-1882-a.html

 

[Engineer54]

It would matter if the RCD in question wouldn't disconnect in the required time

So what do you think i meant by this statement then??

so long as the RCD device passes the standard tests