200amp isolator at cutout position.

[rattlehead85]

I am currently working on a contract replacing lateral main cables to a block of flats including installing a new 3 phase Ryefield with BS88 63A fuses. Is there any requirement to provide a 200amp 3 phase isolation switch between the DLO 200amp service head and my Ryefield board. If so what reg/regs from bs7671 confirm this.

 

[DHES]

Working for a local authority at the moment doing the design side for these type of jobs ie lateral mains and we have an agreement from the DNO saying no to install an isolator or switch fuse before a ryefield because it will be possible for a remnant to isolate and run a in metered supply to the flats. I think this makes sense


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[DHES]

Remnant should be tennant


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[rattlehead85]

Cant say i get that theory. The intake room is locked and not accessible by (Tenants)
and secondly both the Ryefield and Isolator are locked. How would a meter be installed by a tenant in this case without shutting the block off?

 

[DHES]

We have had loads of issues in the past the undesirable tennants who think that they should not pay for the electricity for growing herbs have shut off the isolators in the middle of the night and run there own cables to the flats then just switched back on and all other residents think it was a power cut


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[DHES]

1st post should have said un metered supply (bloody predictive text)


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[Guest55]

does the ryefield board have a main switch switch rated at 200 a ?
if yes , then no isolator required
if no , then you need a 200a isolator.
dont have a reg but single point of switching is required whether the mains room is secure or not.

 

[DHES]

As I said the local authority have approval from UKPN in this case but the authority you are working for may be different. Ask the design engineer the question and see what he comes back with


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[Guest55]

if someone with a bit of skill wants to tap off some free power they can do it regardless of whether theres an isolator fitted or not.
that is a building security issue and shouldnt impede on the requirement to have a single point of isolation for the entire installation.

 

[rattlehead85]

does the ryefield board have a main switch switch rated at 200 a ?
if yes , then no isolator required
if no , then you need a 200a isolator.
dont have a reg but single point of switching is required whether the mains room is secure or not.

The ryefield has no main switch. Tails terminate into busbars at bottom of fuses. Therefore the only point of isolation would be to pull the main service head fuses which are sealed to prevent unauthorised removal. Therefore how the hell do you turn off in case of emergency?
Also all this agreement carry on.., where does that leave me when it comes to completing an NICEIC cert.

 

[rattlehead85]

A non skilled person could still bypass their meter by pulling the associated flat fuse out of the ryefield anyway regardless of an isolator being there or not. So the theory of an isolator permitting an unskilled person to switch off to bypass a meter doesn't really stand up.

 

[Guest55]

well youve answered your own question , no its not right.
as for the cert , well i'd point out this flaw to the client before you start tbh.

thinking some more about it , i'd want it in writing no isolator is to be fitted then record the deviation on the general comments part of the EIC

 

[rattlehead85]

well youve answered your own question , no its not right.
as for the cert , well i'd point out this flaw to the client before you start tbh.

Thanks mate. The local authority say they dont want it put in so i guess when the work is completed this will be recorded as a departure on page 1 of the installation certificate. At least i assume this covers me if the departure highlights the fact the client has refused this.

 

[Engineer54]

Working for a local authority at the moment doing the design side for these type of jobs ie lateral mains and we have an agreement from the DNO saying no to install an isolator or switch fuse before a ryefield because it will be possible for a remnant to isolate and run a in metered supply to the flats. I think this makes sense 

I hope that your local Authority has this foolish waiver in black and white on official company paper!! Since when does the DNO hold sway over fundamental safety, emergency, switching arrangements??

Thanks mate. The local authority say they dont want it put in so i guess when the work is completed this will be recorded as a departure on page 1 of the installation certificate. At least i assume this covers me if the departure highlights the fact the client has refused this.

No, not unless you can provide proof!!!

Again, who is the person responsible actually instructing you to depart from BS7671?? Is he, or the authority taking the full legal and/or civil responsibility for this safety omission instruction, or are they going to pass the buck on to you, if or when that safety omission contributed say, to the loss of life and or the building??

To both of you, ....get an official written instruction my friends, and keep it in a long term safe place!!! lol!!

I still have around 12 to 14 written instructions, which i have insisted on, for work carried out against contract specifications over the years. One of which, came in very handy long before any court proceedings ensued!!!

 

[Guest55]

E54 ,

someone has stuck a tacky red e-pub sticker on your avatar !!
is this something to do with last nights' halloween ? trick or treaters ?
;-D

 

[ayjay]

i tryed clicking on it to see if i could get a free pint biff!

E54 ,

someone has stuck a tacky red e-pub sticker on your avatar !!
is this something to do with last nights' halloween ? trick or treaters ?
;-D

 

[Andyfm]

Back to topic, the ryefield board becomes part of the incoming supply once sealed so not your responsibility, is it?
Its installed before the meters or not ?

 

[rattlehead85]

I hope that your local Authority has this foolish waiver in black and white on official company paper!! Since when does the DNO hold sway over fundamental safety, emergency, switching arrangements??



No, not unless you can provide proof!!!

Again, who is the person responsible actually instructing you to depart from BS7671?? Is he, or the authority taking the full legal and/or civil responsibility for this safety omission instruction, or are they going to pass the buck on to you, if or when that safety omission contributed say, to the loss of life and or the building??

To both of you, ....get an official written instruction my friends, and keep it in a long term safe place!!! lol!!

I still have around 12 to 14 written instructions, which i have insisted on, for work carried out against contract specifications over the years. One of which, came in very handy long before any court proceedings ensued!!!

So what reg/regs in bs7671 does this 'lack of isolator' contrevene? I am firmly of the belief that this installation should and does require one but unless i can back this theory with cold hard facts i will almost certainly be accused of ramping the job up needlessly.

 

[Deleted member 26818]

To my mind the Ryefield board and it's supply are part of a 'system for the distribution of electricity to the public'.
As such they do not fall within the scoe of BS7671.

The Regulation that requires each installation to have an isolator is 537.1.4.

 

[Engineer54]

E54 ,

someone has stuck a tacky red e-pub sticker on your avatar !!
is this something to do with last nights' halloween ? trick or treaters ?
;-D

I Agree, ....It is ''tacky''!! Especially as no-one could ever call me a drinker, or a ''Pub'' man...
Didn't even realise it was Halloween yesterday, not something the locals here celebrate. They have their own Ghost festival, where they go to they're ancestors graves and leave food and paper money!!...lol!!

 

[Guest55]

So what reg/regs in bs7671 does this 'lack of isolator' contrevene?

reg 537.1.4

quote ;

"At the origin of the installation a main linked switch or circuit breaker should be provided as a means of isolation and interupting the supply on load"

edit spin beat me to it lol.

 

[Engineer54]

To my mind the Ryefield board and it's supply are part of a 'system for the distribution of electricity to the public'.
As such they do not fall within the scoe of BS7671.

The Regulation that requires each installation to have an isolator is 537.1.4.

That's fine if this part of the installation is being carried out by the DNO themselves (or their designated contractor) under the scope of their own rules. But this is clearly not the case here, as far as i can tell from the two OP's, who rightly so, are following BS7671, ....or trying too!!!

 

[Guest55]

To my mind the Ryefield board and it's supply are part of a 'system for the distribution of electricity to the public'.
As such they do not fall within the scoe of BS7671.

The Regulation that requires each installation to have an isolator is 537.1.4.

if the ryefield board is to become part of the supply / distribution equipment , then you'd think it would be fitted by the dno or its subcontractors rather than a private installer such as the OP.

and does this mean that if isolation or fuse replacement for individual units is required in the future , that the dno have agreed to undertake this task themselves ?

a strange and inconvienient set-up if so.

edit ; damn , beaten by e54 this time lol , blast this 1 finger typing.

 

[Guest55]

in my experience , the dno's dont want to even take responsibility for their own earth connection these days , nevermind a buildings fuseboard.

 

[Deleted member 26818]

It is no longer the case that the DNO or their 'designated contractor' always conduct the work required.
Even with standard new build houses, the contractor building the houses install meter cupboards and often underground cabeling.
Often all the DNO have to do is make off an underground joint in a supply cable down a hole that the contractor building the houses has dug.

 

[Guest55]

It is no longer the case that the DNO or their 'designated contractor' always conduct the work required.
Even with standard new build houses, the contractor building the houses install meter cupboards and often underground cabeling.
Often all the DNO have to do is make off an underground joint in a supply cable down a hole that the contractor building the houses has dug.

the example you discribed above concerning new build housing is a million miles away from the scenario being discussed in this thread to be honest.
and as you admit yourself , the dno will want to make the final connections themselves for any equipment under their scope , which isnt going to happen with a third party fitting the ryefield board.

 

[Guest55]

and if the work is not under the scope of bs7671 then the OP need not issue an EIC then ?

 

[Engineer54]

edit ; damn , beaten by e54 this time lol , blast this 1 finger typing.

I'm also, basically very much a one finger typing guy. Maybe i've been typing one fingered a lot longer than you, way back into the era of the desk top typewriters even...lol!!!

​

 

[Engineer54]

It is no longer the case that the DNO or their 'designated contractor' always conduct the work required.
Even with standard new build houses, the contractor building the houses install meter cupboards and often underground cabeling.
Often all the DNO have to do is make off an underground joint in a supply cable down a hole that the contractor building the houses has dug.

I can understand what your saying here Spin, all this work being undertaken by the contractor to accommodate DNO installations would be via a well documented deal, brokered between the contractor and DNO to keep costs down for the contractor. But and it's a real but too, The DNO would have issued the contractor with a work specification schedule that the DNO would have been keeping an eye on too, via regular inspections checking on adherence to those specifications. In effect the contractor has become by de-fault if you like, a limited scope designated installation contractor...

 

[Deleted member 26818]

I think a lot of this is probably down to semantics.
An installation would require an isolator, and an EIC, whereas a system would not.
As for the DNO making final connection, we don't know what has been agreed.
Obviously at some stage during the work, the system will require de-energisation.
It may be that the DNO will pull fuses, either in the intake room, or perhaps even at the sub station.
It will all depend upon what deal has been brokered with the DNO.

However at the end of the day, unless the individual meters are placed between the DNO head and the Ryfield board, this is a 'system to distribute electricity to the public', and as such the requirements of BS7671 do not apply.

 

[Engineer54]

I think a lot of this is probably down to semantics.
An installation would require an isolator, and an EIC, whereas a system would not.
As for the DNO making final connection, we don't know what has been agreed.
Obviously at some stage during the work, the system will require de-energisation.
It may be that the DNO will pull fuses, either in the intake room, or perhaps even at the sub station.
It will all depend upon what deal has been brokered with the DNO.

However at the end of the day, unless the individual meters are placed between the DNO head and the Ryfield board, this is a 'system to distribute electricity to the public', and as such the requirements of BS7671 do not apply.

If that's the case, it's as Bif stated then, No EICR is required for this work. Can't have a report based on BS7671 being applied to an installation outside of it's scope...

 

[sedgy34]

I am currently working on a contract replacing lateral main cables to a block of flats including installing a new 3 phase Ryefield with BS88 63A fuses. Is there any requirement to provide a 200amp 3 phase isolation switch between the DLO 200amp service head and my Ryefield board. If so what reg/regs from bs7671 confirm this.

As your replacing mains cables I can't see DNO being involved you should fit kmf units before the ryfield board on the outgoing side to each flat, on new builds you would have to fit your own earth cables as metering have also passed the buck on it.