Grounding, Earthing and Bonding

3 comments

Rate

wareagle Guru Join Date: Jun 2008 Location: Alabama Posts: 1604 Good Answers: 63	Grounding, Earthing and Bonding 11/08/2008 1:09 PM
	Previously there was a question regarding grounding limits and received the following comment: "We do earthing to provide lowest resistive path to the fault current. If the earth resistance is high ~ 5 ohms or more & fault current receives path less than 5 ohms will travel to it and might cause serious issues." My question is about terminology. Does earthing mean grounding as installing a ground rod or does it mean bonding with a conductor. In the US, the earth is never used as a return path for a fault. Equipment grounding conductors are used to bond the equipment to the main panel and grounding electrode conductor to provide a return path for fault currents.
	Register to Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!

V.I.Abraham Guru Join Date: May 2007 Location: Pune , India Posts: 875 Good Answers: 42	#1 Re: Grounding, Earthing and Bonding 11/09/2008 11:07 AM
	IEEE std 80-2000 gives clear idea of earthing of substation. Please read it for correct knowledge regarding earthing. " 3.9 Ground A conducting connection ,weather intentional or accidental by which an electric current or equipment is connected to earth or to some conducting body of relatively large extent that serves in place of earth" "3.10 Grounded A system circuit or apparatus provided with a ground return circuit and for maintaining its potential approximately the potential of earth "
	Register to Reply Score 1 for Good Answer

noshorts Power-User Join Date: Jun 2008 Location: Olive Branch, Ms. USA Posts: 124	#2 Re: Grounding, Earthing and Bonding 11/10/2008 9:19 AM
	This is true but the panel is grounded to earth either via a ground rod or occasionally a cold water pipe. When the panel is grounded the equipment grounding conductor and the grounded electrode are of the same potential. the equipment grounding conductor and the grounding electrode are essentially the same electrically. They have different nomenclature to differentiate their respective locations in the circuit. Bonding is when the neutral bus is bonded to the panel effectively giving it the same potential as the ground. The neutral conductor serves two purposes. provide a return path for the circuit. carry any unbalanced current. ie. if A and C phases are carrying 12 amps and B phase is carrying 14 amps, the unbalanced current of 2 amps is then carried by the neutral. __________________ Tell 'em what they need to hear; not what they want to hear!
	Register to Reply Off Topic (Score 5)

Chankley Power-User Join Date: Sep 2007 Location: South coast of England Posts: 411 Good Answers: 36	#3 Re: Grounding, Earthing and Bonding 11/10/2008 9:39 AM
	In general terms Earth and Ground are synonyms, the USA uses Ground and the UK Earth. Of course earthing/grounding is a large and specialist topic and there are a large number of country and industry specific terms in use.
	Register to Reply

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!

Copy to Clipboard

	Got Something to Say?
	Ask a Question Start a Discussion

	Aerospace
	BioMech & BioMed
	Chemical & Material Science
	Civil Engineering
	Communications & Electronics
	Education and Engineering Careers
	Electrical Engineering
	General Discussion
	Instrumentation
	Manufacturing
	Mechanical Engineering
	New Technologies & Research
	Software & Programming
	Sustainable Engineering
	Transportation

	Site Directories
	Forum Directory Blog Directory User Group Directory RSS Feeds CR4 Rules of Conduct CR4 FAQ Site Glossary Who's Online (52 right now) Show Members