A G.I perforated earthing pipe is a galvanised iron pipe with holes along its length. It is the electrode in traditional pipe earthing: the holes let water poured down the pipe reach the charcoal and salt packed around it, keeping the surrounding soil moist and conductive.
Where it is used
- Earthing for homes, shops and small commercial buildings.
- Earthing of motors, pumps and small distribution boards.
- Sites where a low first cost matters and someone can water the pit regularly.
How pipe earthing is installed
- A pit is dug or bored at a spot that stays reasonably moist, clear of foundations.
- The perforated pipe is placed vertically in the centre.
- The space around it is filled with alternate layers of charcoal and salt, and then soil.
- A funnel at the top allows the pit to be watered.
- The earthing conductor is bolted to the pipe, and an inspection chamber with a pit cover is built over it.
Keeping it working
Pipe earthing needs watering, more often in dry months, and the salt gradually washes out, so the resistance rises over time. Test it every year and recharge it when needed. Corroded connections at the top of the pipe are a common cause of failure and are easy to fix during testing.
Pipe earthing or chemical earthing?
| Pipe earthing | Chemical earthing | |
|---|---|---|
| First cost | Lower | Higher |
| Watering | Regular | Not normally needed |
| Resistance over time | Rises as salt washes out | Stays steady |
| Best for | Small loads, moist soil, tight budgets | Industrial, commercial, dry or rocky soil, sensitive equipment |
Perforated pipes are also used as the outer pipe in some chemical electrode designs. If you are unsure which suits your site, ask us.
Sizes we supply
Our G.I perforated pipe is made in Howrah in 25 to 100 mm diameter, 2 m and 3 m length, with charcoal, earthing salt and pit covers to go with it. For a maintenance-free alternative, see our G.I chemical earthing electrode.