Earth continuity conductors

[ians]

How many of you still install earth conductors as we have in the old days?

I have been spending time reading the SANS book to find ways to cut costs.

6.12.1.1 An earth continuity conductor

Do you install a 6 mm wire if you run a red and black 6mm or do you use a 4 mm wire.

If you look at table 6.28 ... protective device 40 amp ... so long as the cable is not longer than 80 m a 4 mm earth wire is fine.

If you look at twin+e or armoured cable ... those little earth conductors used are a fraction of the size in comparison to the live conductors.

[GCE]

Hi Ians

I assume you looking at ED2 of Sans table 6.28 - Ed 3 is a whole lot different but there are other factors that come into play.
In Ed 3 the distance for 4sqmm earth is now 40m depending on external factors - It is no longer as str forward as sizing the earth one size down on the phase conductor and not really using greater than 70sqmm BCEW

We generally use ECC cable which has a different set of dynamics and the fault current path is calculated by the manufacturer and takes into account surface area to dissipate the heat on a fault current besides the thickness of the copper.
I am assuming that it is similar with T&E and surfix and that the earth being used is calculated based on the max current that can be drawn on the length of surfix you use.

With single cores it changes

[ians]

Too late its already installed this morning ... if it was safe enough for ed 2 ... I am sure it will be fine ... It seems I am going to have to purchase ed 3 ... anyone know if there are any changes ... upgrades or modification in the next few months ... I dont want to go waste money buying ANOTHER BOOK to add to my already full shelf of SANS books?

[GCE]

... anyone know if there are any changes ... upgrades or modification in the next few months ...?

How long is a piece of string ?

Have not heard anything that is changing shortly - Ed 2 was valid for 3 years - We not quite into the first year of ED3 yet so hopefully still 2 and a bit to go.