How far to go with testing?

[flyingsparks]

If you change a main distribution board located at the origin of an installation which has submains coming off to other DB's how far would you reasonably be expected to go with the testing? In the past I have been led to believe the whole installation would need testing and bringing up to date, but surely that could be a massive job in somewhere say like a hospital!

Is it acceptable to just test the submains and note as such on the EIC?

 

[ban-all-sheds]

No - you have to be sure that every single part of the entire installation complies with all of the regulations, or you may not even replace a fuse in an FCU.

 

[securespark]

Poppycock.

 

[flyingsparks]

No - you have to be sure that every single part of the entire installation complies with all of the regulations, or you may not even replace a fuse in an FCU.

So your saying if a main switch at the origin of an install at a large factory burns out you couldn't replace it without testing and making sure the entire factory is up to current regs? Really?

 

[diyer56]

I think BAS may be making reference to the following thread:
//www.diynot.com/forums/electrics/jobsworth.409468/

I am sure he will correct me if I am wrong

 

[ban-all-sheds]

I am referring to that.

And this is why:

I don't think I would get evolved with a job like that if I wasn't reasonably confident that the rest of the installation wasn't bodged, potentially dangerous and never complied to BS7671

 

[RF Lighting]

Absolutely pathetic. Go away and stop ruining our forum.

 

[ban-all-sheds]

I'm not. No, and I'm not.

 

[ericmark]

You are permitted to enter limitations to the work you have done. So as long as you say in the paperwork what the limitations are then acceptable. So for a main distribution unit it would be common to limit testing to the next distribution unit.

So the unit with moulded breakers would have an inspection and test to the sub-unit with MCB's but no further.

There are cases where it would not even go that far. And only the cable ends would be tested. I have had this many times where the next box belongs to some one else.

I have also been required to give power to a box with MCB locks on some circuits where other electricians are working on that circuit in which case can't even use a insulation tester on the locked off circuits here we get into permission to work.

On sites with 100's of electricians clearly you don't want to be working on a cable and have some other electrician use an installation tester so there would be a permit system and the permit says what you can do.

Clearly with a hospital there will be some circuits which must not be turned off and also likely other electricians and other trades working at the same time. Also there will be locked rooms where drugs are kept and limits where one can go because of other medical considerations.

Although it may not say permit to work there will be a document which will lay down the limits and you have to work to those limits. The next distribution unit I would unless otherwise indicated in paperwork I would take as the limit.

Even in a house there are limits. Once one reaches a FCU or a socket that would be the limit after the FCU it's a different circuit on it's own overload protection. Even an isolator can be considered as a limit so with an isolator which requires a tool to switch it one then that would be your limit. Even a tie wrap which needs snips to remove it would count.

In a simple house I would test supply to cooker but I would not switch on every ring and oven option to me we test the installation not equipment connected to the installation and the cooker is equipment not the installation.

I note the ESC does not see it this way. They advise one should fail an installation if there are adaptors and extension leads plugged in which form a danger. To me to fail a new house because the builder has a load of extension leads running through door ways is daft. After the socket is beyond the remit with a EIC or an EICR. However the ESC does not see it that way.

What we have to remember is when we inspect and test we give a professional opinion. Testing our own work would be covered by public liability insurance but testing some one else's work may need professional indemnity insurance. So going beyond one remit could cause problems in the future.

 

[ericmark]

I would advise this is a DIY forum and work in a hospital is not really DIY. I would be posting a question like this on the IET forum which is more designed for trade questions.

 

[flyingsparks]

I would advise this is a DIY forum and work in a hospital is not really DIY. I would be posting a question like this on the IET forum which is more designed for trade questions.

Thanks Eric. I only used a hospital as an example. The job in question is actually a farm where the supply comes in to an out building and then submains feed off to the house, milking parlour and other farm buildings. If one was to replace the DB at the origin, could you get away with putting on the EIC limitations that only the submains were tested up to the next DB. Any other non-conformaties after that would be a limitation on the EIC. Although would be a good idea to make the customer aware that there could still be potentially dangerous situations present.

 

[ericmark]

I am sure you realise farms are rather special. I remember in my C&G2391 exam there was a farm given as an example and I was having kittens as I had never revised on special locations I felt it was a really sneaky question but I passed so clearly my guess worked out. I will admit it was a guess.

Many years ago before the supply company would connect the supply they would test the whole house. Those days are gone it was clearly easy to have a consumer unit with a single double socket then once supply was provided one connected up the rest so today there limit is the consumer unit and if that's OK they don't go any further. I stand to be corrected on this.

To me you have the same option if the consumer unit or distribution unit it feeds is OK personally I would state limitation on the installation certificate and limit my testing to the supply to the various distribution units and no further.

However the distribution unit / consumer unit question is something I am not so sure about. Is a farmer an ordinary person???

 

[OwainDIYer]

Farms are notorious for dodgy bodges and wiring unsuitable for its environment.

You shouldn't energise anything unless you're satisfied that it's reasonably safe. I'd suggest at least an insulation test of the sub-DB (with circuits connected if possible, circuits disconnected if not possible to test due to connected equipment), earth continuity, and polarity check and Zs at a sample socket. But visual inspection would guide you - if you find old iron-clad switchgear, implausible earthing etc then you need to get firm with the customer. This may mean risk losing the job, but better that than be up in court at a later date.

 

[flameport]

In a theoretical world, you should test every circuit, open every socket, switch and other accessories, examine 100% of all cables and wiring, fully test every motor and machine, open and inspect all luminaries including those mounted 30ft above the floor, and of course repair every minor defect so that it totally complies with BS7671 in every way.

In the real world, things are done rather differently.

As for EICs and other documents - they can say whatever you want to write on them, and cover as much or little of an installation as you deem necessary. It's your name on there after all.

 

[JohnW2]

In a theoretical world, you should test every circuit, open every socket, switch and other accessories, examine 100% of all cables and wiring, fully test every motor and machine, open and inspect all luminaries including those mounted 30ft above the floor, and of course repair every minor defect so that it totally complies with BS7671 in every way....

Indeed, but in that same theoretical/hypothetical world, you would not do all that just when you were doing work and completing an IEC, but routinely at least once every day!

In the real world, things are done rather differently.

Quite so. Although many aspects of the modern world unrealistically strive towards the hypothetical world you describe, there is thankfully still some scope for exercising good old-fashioned common sense - or, at least, 'pragmatism'.

Kind Regards, John