Surge Protector -- Auto Detect Wire Connection? Earth?

Elementary Dear Dr. Watson..

Electrical grounding varies from country to country, region to region. But the object is the same. Safe electrical discharge. It is always a galvanized piece of metal, but not copper or zinc or platinum

Why do they normally use a hollow pipe ? They are nearly always galvanized, and increase the surface for safe discharge of lightening should one hit your house.

Why salt ? because surrounding earth might not be a good conductor. Salinity to the soil makes a better conductor. Places that have very high ground water drainage, and low salinity requires periodic testing for salinity.

One never uses copper or other metals to connect to the Earth ground because of erosion. Typically in standalone houses, the rainwater drainage pipe substitutes for Earth Ground, provided it meets the national code. You can check whether you can use a piece of pipe outside your house if it has 0 voltage.

@Elementary Dear Dr. Watson..

In Goa the 'ground' is iron-rich laterite, I would have thought it would provide a good electrical earth even when bone-dry (and without needing salt) but I can't really think of a way to test this theory. I could drop a wire down the well and measure the potential between that and a buried wire, but I think I will get a 0v reading if they are the same potential OR if I've got an open circuit (i.e.dry ground not conducting).
Until quite recently in the UK appliances could be earthed to a nearby copper water pipe, this is no longer allowed because so many water systems are now all or part plastic. This idea of separately earthing appliances is either a hang-over from when 5-amp circuits had no earth or lack of faith in the integrity of the ring-main earth.
Outside earths were often buried in or near drains because the ground would always be damp.

what sort of pipe, and 0v compared to what?

AndyD 8-)#

Grounding pipe<-----Voltmeter--------->conducting element etc. If there is voltage then the grounding pipe has static/residual current/

With regards to laterite, you would have to check the ISI document. North American standards do not have iron-rich laterite as an acceptable ground.


In itself earth is a poor conductor, and discharge to earth recommends a degree of salinity (because it is the cheapest) and moisture. This combination reduces the resistance of the soil.

I think BIS 3043-1987 is the document that specifies Earthing specs. in India.