• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Earth

Status
Not open for further replies.

Electronman

New Member
Hi,

I am not able to understand why the Earth is a conductor for the electricity?
What's the main reason of using the earth except of nulling the electric stuffs?
Can I lighten up a 12V lamp by conducting one lead to a 12V battery and the other lead to the earth while one lead of the battery is connected to earth too??
If there is any link to light me up I would be appreciate for it!

Thanks
 

solis365

New Member
Electricity is simply a flow of electrons between potentials (voltages). "Earth" is referred to as 0V to make for convenient notation. The "earth" provides an infinite source and sink for electrons (whichever is needed). Basic electronic theory does not allow for electrons to "build up" anywhere, and they always have to be moving. Considering these two facts, you have to have a place for electrons to come from and for them to go - this is earth. A point that, for basic circuit analysis, is infinitely conductive and is thus always at the same voltage.

And yes, your idea with the light bulb and the battery will work, as long as your "earth" is an ELECTRICAL earth (this means it is very very conductive). If you just shove two wires in the dirt it may work and it may not, depending on the dryness of the soil and mineral content and such.

Earth is used in mains AC powered devices for protection (the third prong of the plug is earth). basically if a high-voltage part of the circuit touches the metal case of the device, all the current will flow into the earth connection (infinite current sink) since the metal casings are connected to this third prong. This will prevent you from getting shocked if you touch the metal case while it is malfunctioning.
 

Electronman

New Member
Thanks a bunch for your reply,

Well I think I vaguely understood you.

I think at a normal temperatures just Metals have the conductive property.
If the earth is a relative conductor depending on its minerals and the water on it so it is not a good conductor and can not provide a good protection for humans.
Besides Can you let me if we can use the earth instead of the null wire?
does the null wire comes from the earth in somewhere or it comes from the powerhouses?

While in the cities there are several step-down transformers and they seem to be isolated from the high voltage wires which come from powerhouse then why we have a closed circuit in our houses (I mean why the phase and the ground can be related to each other while there is no closed circuit..)
 

EN0

Member
Might I imply:

"Earth to Electronman!" "Earth to Electronman!"

Just couldn't resist!:rolleyes:
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top