earthing rods

[shrimp]

Hi peoples,
I am thinking of installing outside power to my shed i am going to use 4.0mm 2 swa cable(should this be 2 core) also does the cable running from have to be the same size as the swa cable.
This cable will be going into a garage unit and then running a double gang socket and a light.
What i was wondering is if anybody know the going rate for a sparky to test the earthing rod .
Cheers

 

[breezer]

who says you need an earth rod?

try doing a search for power to garage etc ect

 

[shrimp]

well i put another topic on this a week ago under shed electrics and people we're saying because i had pme earthed house to use a earthing rod.
Originally i was going to go from the back of a socket because i now have had 2 eletrician say they would go from there so i'm confused now
So what do you think

 

[breezer]

it helps when posting if you link to previous questions / what your q apertaines to.

I was one of those who said you should not come from the back of an existing socket.

The reason is its dangerous and a bodge end of story.

why not get more quotes, (or say you dont want it taken from back of socket) yes it will cost more but it will be safe and correct.

 

[shrimp]

Sorry about that

will i can do all the leg work myself it just getting the rod tested and the rest of the system.
So i was wondering if anybody know what sort of price i could be looking at for testing.
also can you go from 2.5 from the cu to a box outside to the 4.0 swa or do they need to be the same

 

[andy]

Sorry about that

will i can do all the leg work myself it just getting the rod tested and the rest of the system.
So i was wondering if anybody know what sort of price i could be looking at for testing.
also can you go from 2.5 from the cu to a box outside to the 4.0 swa or do they need to be the same

since part P will apply, LABC will test/certify it.

you can use 2.5 in the house and 4mm outside, however, you will only be able to use a max of 20A because of using the 2.5 cable. use 4mm and you have have 32A. itll be best to keeo them both the same at 4mm. or better still, use the SWA to CU area instead of T&E


as already mentioned, dont make it a spur from the ring. it can be done, but its not advisable. if there is a fault in the garage, ill take the house ring main out, aswell as the fact youll have a maximum of 13A to play with, and you can easily go over that depending on what your doin

 

[shrimp]

ok nice one the only reason for trying to go for a smaller size in the home is because the cu is a the front of the house so i need to run through the house with the cable in trunking

 

[andy]

ok nice one the only reason for trying to go for a smaller size in the home is because the cu is a the front of the house so i need to run through the house with the cable in trunking

you could take the SWA around the house, fixed to a wall... and the physical size between 2.5 and 4 isnt much

 

[shrimp]

Plus that would be a bit expensive run in all swa cable.
But thank you all for the help

+++++++++++++++++++++++++++++

Oh yeah just one more thing should i use 2 or 3 core cable
_____________________________
moderator

please note 10a

 

[breezer]

Oh yeah just one more thing should i use 2 or 3 core cable

try reading as i suggested, shed electrics, etc the answer / debate is there

 

[Tommy Tank]

Take 2.5mm2 cable from back of socket to fused connection unit next to socket or on back wall of house.Drill through wall and take 2.5mm2 cable from F.C.U and run in conduit from house to garage.Then fit whatever points required knowing that all will be protected from 13A supply in house.Just limit load accordingly.This way is cheapest, easiest and complies fully with BS7671.Or do it the way suggested above for more demand if needed.

 

[andy]

Take 2.5mm2 cable from back of socket to fused connection unit next to socket or on back wall of house.Drill through wall and take 2.5mm2 cable from F.C.U and run in conduit from house to garage.Then fit whatever points required knowing that all will be protected from 13A supply in house.Just limit load accordingly.This way is cheapest, easiest and complies fully with BS7671.Or do it the way suggested above for more demand if needed.

^^above will only work if max demand is 13A. also, if there is an earth fault, it could easily take the ring main out and you could be without sockets workin. aswell as the fact doin it that way is just a bodge job to do it cheaper

 

[Tommy Tank]

Nothing bodge about that method mate.He said only 1 twin socket and 1 light so why would 13A load be exceeded without using ya nouse?Why should there be an earth fault if it's done properly ( because it could get damp in the garage )?Not if it's all IP rated.So what if it takes the house ring main out the so called faulty leg can be isolated at the F.C.U!This method was a different idea from all mentioned and fully complies with BS7671 and is most definately NOT BODGE, well unless you do it maybe!

 

[shrimp]

ok people no fighting now here what i shall be using in the shed see what you think.circular saw,router,drills,planer,lights,maybe a battery charger for cordless drills and Radio controlled batteries.and stereo and maybe a heater.there will only be a twin gang and a strip light,

 

[andy]

ok people no fighting now here what i shall be using in the shed see what you think.circular saw,router,drills,planer,lights,maybe a battery charger for cordless drills and Radio controlled batteries.and stereo and maybe a heater.there will only be a twin gang and a strip light,

hmmm.... 2KW (possibly more) heater, battery charger, circ. saw plus others.... so, even you have just admitted your total power need will be over 13A. so, it looks like youll get sick of blowing a 13A fuse and put a nail in place of the fuse. so, tommytank, this isnt a bodge job then?