eathing

[cmossom]

hi could anyone shed some light on this for me???

I am about to do my NVQ 3 and decided to do my inspect and test bit on a board at my house.whilst looking at the board i noticed that the earthing goes under the floor and is wrapped arroud a lead pipe and doesn't even have a clamp!!

i phoned united utilitys and they only maintain the eath they don't supply it so they wont come out and i need a tt rod i suppose anyone have any thoughts on what i need to do or the easy option as im doing the board on thursday with the assesor

 

[EFLImpudence]

Can we have some pictures of the cut-out and CU please?

 

[Lectrician]

Yup, pics, including the conection you describe.

 

[cmossom]

will try not sure how i put them on here.

 

[cmossom]

the connection on the lead pipe?? thatsunder the floor and just twisted around it.. its a water pipe i now that much

 

[audi100]

As you know you have a TT system. Krimp an extension to the earth cable and run to the outside of the building and clamp onto an earth rod and then put an earth pit over the rod for inspection purposes. Then using an Earth loop tester measure the earth loop reading, You must measure with the earth cable disconnected off the earth terminal. Once tested reconnect the earth cable to the bar. An acceptable reading would be below 100 ohms. This type of earthing system must be protected by an RCD. So check it's tripping times. The earth cable from memory should be a minimum of 10mm I think. If you do not have an RCd then you must install one. If its an old voltage trip ditch that. As they are susceptible to parallel earth paths.

 

[cmossom]

i presume once i put an earth rodin it will be a tt system at the moment it does have an eath but would the be ok with a clamp to the lead water pipe??

dont think i can put an earth rod and inspection pit in b4 thursday so i guess im screwed..

I payed an electrician 3 years ago b4 i new anything about electrics to do the bonding for me when i had the boiler fitted so i guess when he did that he did the main eath aswell and had me for £100 hahaha ****ing sparkys hahaha only joking guys!!

 

[audi100]

Is Your Assessor looking to see if you understand what you are doing? or is the assesor looking to test your work? You didn't install it did you? So you need to demonstrate you know the correct way to do it. The services need to be bonded (water and gas/oil) are the common ones. The local electricity supplier nowadays supplies a means of earthing. If this is not supplied then you have to do it. Your only cost effective method is a TT system. If the main earth path in your house is the cable twisted round the lead pipe. Then you do realise that this situation is not acceptable?
Do you have an Rcd installed? If not, do not bring the assessor anywhere near this house. If he's good he will be looking for what you know is right and wrong and not give you too much of a hard time.

 

[cmossom]

cheers for that..

The plan is to install a 17th ed board n test it as im a practising operative i don't have 2391 so i cant sign it off so the guy i work with will be watching and providing the cirt.

for my portfolio he will take pictures of me installing and testing and commission so he wont be looing at the earthing just would be good to have it sorted b4 i change the board.

i have the old rewirable fuses at the moment but that would be getting taken out or so the plan was.. lol

the assessor would just be taking pictures not really testing me as i am just a practicing operative under supervision kind of a trainee so the nvq3 is not what i would call a very good qualification as experience is the best qualification you can get.. anyway is an earth rod an expensive fit with the inspection pit and can it be done quickly

 

[audi100]

I would expect an earth rod and pit to be approx £35.00. Good luck.

 

[cmossom]

is that with it fitted??/

 

[audi100]

No supply only. you could be looking at a labour cost of anything from £60 to £150.00.

 

[cmossom]

is it hard to do, i havnt ever done one b4 does the earth rod have to be outside or could it be in the crawl space under the house?

i could fit the rod and connect it and do the Zs Ze when the approved electrician iwork with helps me fit the board for nvq.

does the rod have to go very deep?

 

[audi100]

The Rod needs to be in a position where it can be easily inspected and tested. If you mount it under the floor with say carpet or even laminate flooring is that now easily tested? Anyway you should leave a label or notice on the dist board to inform its location.
I personally think its easy to do. you should try doing it, be confident, make sound electrical connections and never do it live.

 

[cmossom]

do you just pound the rodin the ground??

the rod would be very close to the cu under a hatch in a cupboard under the stairs so mechanical damage woud be very unlikely.

will have a look into it and see what i can do but cant be any harm in having a go.

it will not be carrying any current in the future i hope so i will never need it tutch wood lol