we are putting in a 3 phase board and as its a shop with no large fixtures apart from 3kw heaters, ring main, water heater, lights, and PCs now that's the one how do we make up with 17th edition regs and still make it safe with and cost efficient and conform to 17th regs RCBO's to costly as their are 12 in all RCD's to temperamental for all , with all there data on line . Giz A clue . Cheers

Which particular clue would you like?
3 phase for your situation is just 3 separate single phases and treat as such.
Your biggest problem will be controlling the heating load as experience has shown that running costs can run away.
I used to do a lot of shop installations and it's surprising how much the lighting load can be and the heat generated could be recovered with a bit of planning.

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Norman

Sorry, but your best bet would be to get an electrician to do it, cost efficient & to the regs rarely go together.

If you want to save on the cost of RCBO's, then I suggest that you fit a single phase board supplied from a 60A breaker in the 3 phase board. Fit one RCD to protect this board and that's it job done. But not very well as one earth fault will disconnect all the circuits connected to the single phase board.

Probably not the best advice, as the regs state that circuits need to be split over at least two RCD's to minimise inconvenience/ danger in the event a fault occurs.

It's a shop - its a place of work - EAWR will apply - there will be a duty holder (although they may not know it) - why the fixation with RCD's

Regards

OMS

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Failure is always an option

Is there a flat above the shop.

LoL - I guess your not asking cos you want a place to rent

Regards

OMS

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Failure is always an option

Lol

No I was just thinking that if there was a flat above. You would need one of nobels boys to sign the job off. And op didnt sound to wonderful.

You may say that - I couldn't possibly comment

Regards

OMS

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Failure is always an option

Eh? Very true, but still a requirement under BS7671. What's the chance it's all in steel conduit or run surface. Believe you me, methinks RCD's are a pain especially when the RCD autotest on my new fluke has packed in...

Regards

ABL

Oh dear - I suggest a little canter through BS 7671 particularly Reg 522.6.6 (v) - then move onto 522.6.7 in light of my comments about it being a shop (ie under the supervision of a duty holder

Regards

OMS

Say what you like - it ain't rocket science is it

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Failure is always an option

Perhaps you are confusing duty holder with skilled/ instructed person as they are two different things? Reg 522.6.6 reiterates what I said, unless you're working out the 16th edition...

Do you think so - as I said, if the installation is a workplace then it will have a duty holder - ie a skilled or instructed person who will be controlling the installation and providing information to those who need it (in this case telling anybody likley to drill holes that there may be buried cables and they should identify them before drilling

The use of zones is perfectly acceptable without resorting to RCD's on every circuit.

Regards

OMS

This message uses 100 % recycled electrons - number of polar bears saved - 5

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Failure is always an option

Fair comment and absolutely true if the installation is truly managed and maintained properly by competent skilled and/ or instructed persons.

But it being a workplace and have a duty holder does not neccesarily mean that 1) the 'duty holder' is instructed, nevermind skilled and 2) the installation is under the supervision of skilled/ instructed persons...

Surely it is - and it is - then down to the installer/ designer to make a educated desision as to who is going to use the installation and design it accordingly i.e. rcd or no rcd?

I understand your point and appreciate it. I do however come across a lot of 'duty holders' who do not know they're a*ses from their elbows, and forget trying to explain the EAWR and their responsibility.

Here's some food for thought - a 'duty holder' is a responsible person, no?

Now say a general office bod, call him bod 1, turns up at work 8am to open up & spots a dodgy socket hanging off a wall with live terminals showing (it obviously being serious and needs to be rectified ASAP). This socket came to be in its particular predicament because careless cleaners yanked the cord out on their henry the night before but they do not did not notice that they pulled the outlet out as well. Meanwhile, the office manager is not in till late due to a very important early meeting with a client. Bod 1 ignores the socket and does not say anything or report it, as it is not his resonsibility... Office bod 2 comes in and somehow, touches the exposed live terminals causing severe burns to his hand.

Now here's the predicament, who is truly the responsible person, therefore the duty holder, in this scenario?

"Now here's the predicament, who is truly the responsible person, therefore the duty holder, in this scenario?"

In the example you suggest, or any other example for that matter, an accident investigation would take place, also taking into account relevant legislation, and then relevant and appropriate actions would be taken.

Therefore:

Was there a correct company safety policy?
Were the employees correctly trained to understand their legal and company health and safety responsibilities?
Were the cleaners correctly trained in their company and legal health and safety responsibilities?
Was the socket and its mounting/fixing correctly designed?
Was the socket suitable for its use?
Was the socket correctly installed?
Was the socket correctly checked and maintained?
Were there fault and risk reporting procedures in place?
And so on......

After this we can decide who is responsible, which may be one or more people and for different reasons.

Regards.

It's not that complicated - EAWR simply states that the systems shall not kill or injure anyone (ie the duty is absolute). Regardless of who came in when and said what to who the duty is still there.

Returning to the scenario, the RCD is only intended to offer supplementay protection anyway so relying on it to protect against a direct contact shock is technically not permitted under BS 7671.

The electrical fraternity should be very cautious about shouldering duties that are legally others.

CDM is the instrument by which the designer should ensure the installation is "fit for purpose" in a workplace

Regards

OMS

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Failure is always an option

No one said the duty was not there, but the question was asked who is the 'responsible PERSON' for the scenario suggested.

Actually the overall responsibility and duty is set out by the 'Health and Safety at Work Act 1974' and rests with the employer. Note that this is an 'Act' and the EAWR is a set of 'regulations'. Particular person responsibilities will be established by an accident investigation which is why they are carried out. However should the HSE prosecute they may prosecute the company as a whole or a particular responsible person, or persons, which they will establish from an investigation and the company health and safety policy and statement and the law.

With regards to RCD, and so on, BS 7671 has NO legal status and is only a guide/standard, albeit not following its guidance would likely lead to a less safe system and thus increase the possibility of an accident and successful prosecution, and thus a designer can use whatever method they wish providing the can prove it is safe and fit for purpose. But anyway your advice and information on the use of RCD's is good and thus should be followed.

With regards to CDM there is truth in what you say but actually it is only a part of the overall picture. The responsible person with regards to let's say the construction project will of course have to ensure the right equipment is used and correctly installed but they may use a socket and fixing that is of a particular standard and yet not know that it has a design flaw.....in this situation they have exercised their responsibility correctly but yet the accident happened. Also the socket and fixing may have been installed some years later by a contractor, at the request of the particular company, and thus not subject to the CDM regulations. Fit for purpose, with regards to the socket and fixing design, starts when the product is first designed and thus may be established by FMEA, prototype testing, simulation and so on.

Of course it is simple to say, for the scenario suggested, that the accident happened and that overall responsibility rests with the employer but when we come down to particular people it is not always so simple.

Regards.

I think that was the point I was making - the responsibility rests with the duty holder - it is not an issue for the installing contractor/designer etc - that responsibility sits under CDM.

If the designer can show that he acted responsibly then he has discharged his duty.

Going back to the thrust of the OP and the requirement for RCD's I would suggest that the designer, if he chooses the option that the installation is under control of a duty holder, and hence doesn't include RCD's to protect buried cables and instead relies on "zones" would simply need to communicate this as a residual risk to the principal contractor who will then include this in the project Health and Safety file and thus inform the duty holder - ie they are now an instructed person because they know there are buried cables installed and these might pose a risk to persons drilling or nailing


You might want to check if installation of a socket some years later is actually defined as construction work - I believe that it would also fall under CDM - so the client would have a duty as would the designer and installer(although I accept that the project may not be notifiable)

Regards

OMS

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Failure is always an option

I should also have mentioned the 'duty of care' establised by/under common law but that is another matter. I think we can agree that the overall responsibility rested with the employer and thereafter particular person responsibility, if relevant, will be established by the accident investigation, the law and the company health and safety policy/statement. This is why things can get complicated if/when they get to court.

With regards to how to correctly carry out a job there is plenty of good advice, guidance and experience about, and what you suggest falls into that catagory, and the important thing is to use it rather than just make it up, or guess, as we go along.

Regards.