earth wire size

mickward

Hi Guys,

Not sure if this is a "how long is a piece of string" question and please forgive my ignorance.

this question is in relation to some work which was carried out on my mothers house, the washing machine repair man informed mam she had no earth at the sockets, so i called out a local electircian, he came out and said there is an earth but that their was a crossed phase on the line?????

he disconnected the old earth spike, this was very old cable, but i redid concrete about 2 years ago and i went out and bought a new earth spike and clamp and replaced what looked like an old rusted broken piece of a bed frame (angle Iron) keeping the exisiting wire, put it into the green box and all, good job i thought and the man in the electrical supplies said to fill the box with grease so i did and thought all was good - this is the problem with a little knowledge i understand that.

now when the repair guy siad there was a problem i called out a qualified guy to check it out, he just went to the otherside of the house - no cncrete, drove in a new spike 1m long same as mine leaving about 250mm above ground connected a wire which looks like 4 square, about 5mm outer diameter to the spike with a clamp no box or any protection ran the cable up the side of the house into the attic and to the fuse board, disconnected the old earth and hooked up his.

now the sockets showed earth on his plug tester so everyone was happy but when i seen the earth spike it is a trip hazard and although the ret of the job was very tidy, i was concerned about the size of cable used is it large enough?

also could i drive the spike on down into the ground so no one trips over it?
he is not coming back as he said it is fine and told me to hit he spike with a sledge until i am happy with its height

brightspark

Was he a registered electrical contractor (member of RECI or ECCSA)?

mickward

Hi brightspark,

he is registered and in business along time, 3 generation and his sons are now in the business all proper and they have a great rep.

i dont not trust him and driving the earth spike further into the ground seems reasonable to me.

my question really is should the cable have been put into a conduit it is in behind a down pipe tacked to the wall and the down pipe put back up, so just green and yellow cable.

And then what size should the cable be, it looks small diameter to me.

brightspark

From your description it looks like the following regulations haven't been complied with. I haven't quoted the regs in full, just the relevant phrases.

542.2.3

"Rod...driven vertically into the ground to a depth of 1200mm"



542.3.1

Cable should be 10mm^2 minimum (external diameter would be approx 6mm, but it's the C.S.A. of the copper that matters not the insulation thickness)

"Where exposed to the likelihood of mechanical damage, the earthing conductor shall be suitably protected" (conduit or pipe either metal or heavy duty PVC)



542.3.2

"The connection...to an earth electrode....shall be protected against corrosion by means of suitable protective tape..."



542.3.3

"The connection....shall be enclosed in a suitable box..."


Does the clamp have a tag saying "earth connection do not remove"?

What sort of a tester did he use? Was it just like a plug top with a few LEDs on it, or was it a meter giving a reading of the earth impedance (resistance)

maxfresh

Doesn't sound like good workmanship to me the size cable to the earth rod should be 10 mm square. the clamp should be at the top of the rod wrapped in denzo tape enclosed in a green box with the top of this box flush with the finished ground level.