New job, new problems

[CardboardUncle]

Hi all,

I've recently started a new job making the jump from domestic new build to doing minor works on commercial buildings adding lights to existing circuits etc..
Carrying out the work isn't the issue it's the regulations and paper work side of it. minor works certs etc which I have never had to do before. My understanding is when adding new lights to current circuits, what I add to that circuit is what needs to be up with current regulation? My problem is these buildings I'm working in are quite old so some of them haven't got RCD's protecting the circuits and some may not have earths in the lighting circuits at all. is there any way around these problems by declaring it on the minor works certs or not?

any help appreciated
Thanks.

 

[Octopus]

The model form doesn't include R1+R2 test.

hum, it ask for earth continuity satisfactory - which to me is a dead test, to confirm continuity, and the easiest way to do this is R1+ R2

interestingly the AMD3 version is the same!

I still don't think you should bypass the dead test and go straight for the bang test

 

[SS-2015]

hum, it ask for earth continuity satisfactory - which to me is a dead test, to confirm continuity, and the easiest way to do this is R1+ R2

interestingly the AMD3 version is the same!

I still don't think you should bypass the dead test and go straight for the bang test

ok I guess in a round about way it asks you for the results of R1+R2.

 

[Sintra]

No addition or alteration, temporary or permanent, shall be made to an existing installation, unless it has been ascertained that the rating and the condition of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate.

 

[CardboardUncle]

Having read up on a few things over the weekend am I right in the following:

Any work that I carry out obviously has to be up the 17th standard, but if your adding to a circuit you don't have to bring that entire circuit up to 17th standard only your (new) own work?

The need for an rcd is only required when the cables are in walls and buried at a depth of less than 500mm, So if i were to install a new circuit and mount the cables in plastic trunking and/or clipped direct to joists in a loft space for example this makes the lighting exempt from the use of an rcd? (again i have read this and then somewhere else read they must be regardless)

If they are to be protected regardless, is it okay to add an rcd fused spur as the first point where my work would begin on the circuit and then rcd protect the part of the installation i am going to be adding not the entire circuit.

As said previous this is a new area of work for me and I dont have no where near as much experience as most of you guys on here so any help is much appreciated

thanks.

 

[Richard Burns]

Having read up on a few things over the weekend am I right in the following:

Any work that I carry out obviously has to be up the 17th standard, but if your adding to a circuit you don't have to bring that entire circuit up to 17th standard only your (new) own work?
Yes, your work must meet the current regulations, which may involve changing something in the existing circuit in order to get your work to comply.
The rest of the existing circuit must be safe to be used, but not necessarily up to current regulations.

The need for an rcd is only required when the cables are in walls and buried at a depth of less than 500mm, So if i were to install a new circuit and mount the cables in plastic trunking and/or clipped direct to joists in a loft space for example this makes the lighting exempt from the use of an rcd? (again i have read this and then somewhere else read they must be regardless)
There are specific requirements for 30mA RCD protection as additional protection: all socket outlets <=20A, outdoor use mobile equipment <= 32A, LV circuits within a location containing a bath or shower, cables buried <50mm in a wall or partition, additional special locations of increased risk to persons or livestock. There are exclusions to the above. These would have to be complied with for your work on the circuit or any part you alter.
In your example if you were putting cable in trunking in or through a bathroom this would not exclude the 30mA RCD requirement.

If they are to be protected regardless, is it okay to add an rcd fused spur as the first point where my work would begin on the circuit and then rcd protect the part of the installation i am going to be adding not the entire circuit.
This is acceptable however good practice (and possibly convenience and cost) might indicate that protecting the entire circuit may be appropriate.
On changing a ring final circuit, unless it is only a spur, it is difficult to apply only partial RCD protection.

As said previous this is a new area of work for me and I don't have anywhere near as much experience as most of you guys on here so any help is much appreciated

thanks.

my thoughts in red above

 

[CardboardUncle]

my thoughts in red above

Thanks for the reply.

As for the socket example you are using the rcd would be required. But if it were a lighting circuit with surface mounted cables in trunking not passing through an special locations etc then my understanding would deem it okay to omit the RCD an still be with in regs?

Thanks again

 

[newtothis]

Sorry if this is a silly question - doesn't the "trunking" have to provide mechanical protection ?

 

[Richard Burns]

Lighting, with surface mounted cables, not in a special location, does not need 30mA RCD protection.

The trunking is only there to provide support, possibly visual acceptability and a modicum of protection (if required).
The level of protection required, assuming it is not a high risk area, is the cable sheath only, (think about flexes on equipment!)
Mechanical protection is a range of levels and in a domestic situation unless in the path of constant brushing against or door hitting it, etc. then the sheath should be enough, but nothing to stop you adding more.

 

[Spoon]

Apologise up front is this sounds like I'm teaching you to suck eggs but check out section 543.1.1. (page 164 BYB) if there isn't an earth and you are going to add one.

 

[marc8]

This is not an option for any new work installed.

Should the fitting not require a CPC you are not obliged to run a CPC, so therefore new work or not if you are using class 2 equipment then you don't need to run the CPC.

 

[Andy78]

Should the fitting not require a CPC you are not obliged to run a CPC, so therefore new work or not if you are using class 2 equipment then you don't need to run the CPC.

The presence of a circuit protective conductor is required at all points in a fixed wiring system.
It is not forbidden to take a protective conductor into a class 2 item of equipment.
All new work requires testing and certification, including earth fault loop impedance.

 

[CardboardUncle]

Does this still apply when changing a light to a decorative light for example? If I took down an existing pendant, found there was no earth but was going to be fitting a double insulated light fitting then would you still be required to run a cpc? A lot of people still issue minor works certs for changing light fittings don't they?

 

[Andy78]

Does this still apply when changing a light to a decorative light for example? If I took down an existing pendant, found there was no earth but was going to be fitting a double insulated light fitting then would you still be required to run a cpc? A lot of people still issue minor works certs for changing light fittings don't they?

A minor works cert can be issued for a change of accessory, but is not usually required. Changing of accessories is generally classed as maintenance which does not require certification.

The regs do require a circuit and/or system to be suitable for continued safe use before alteration or addition, so testing should be carried out to prove this, and a minor works cert to prove you have tested is not a bad idea.

 

[marc8]

The presence of a circuit protective conductor is required at all points in a fixed wiring system.
It is not forbidden to take a protective conductor into a class 2 item of equipment.
All new work requires testing and certification, including earth fault loop impedance.

can't see anywhere the regs have changed on it could you point me in the right direction ? class 2 no earth required, I have also asked Technical before that if I had a pendant light with no earth & wanted to change it could I change it yes as long as its class 2, same with adding another light as long as it's class 2 then no need for the CPC old & new.
I did not agree with no earth either but it does not matter as long as its class 2.
on Minor works you would record this as a Limitation as no earth exists for the circuit.

 

[markc123]

can't see anywhere the regs have changed on it could you point me in the right direction ? class 2 no earth required, I have also asked Technical before that if I had a pendant light with no earth & wanted to change it could I change it yes as long as its class 2, same with adding another light as long as it's class 2 then no need for the CPC old & new.
I did not agree with no earth either but it does not matter as long as its class 2.
on Minor works you would record this as a Limitation as no earth exists for the circuit.

411.3.1.1

EDITED..

You can't go failing installations for no earth at lighting points along as the fittings are class 2 as you correctly point out. This regulation is basically for new circuits being installed - and that regulation has been around for a while.