How Do I Test Teed Protection in One and a Half Breaker Scheme.

6 comments

a_chahande Participant Join Date: Nov 2009 Posts: 3	How Do I Test Teed Protection in One and a Half Breaker Scheme. 12/17/2011 10:47 PM
	The scheme has 5 CT arrangement. I need to test both low and high impedance scheme. The scheme is of ABB make.
	Register to Reply
	Pathfinder Tags: One and half breaker protection

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

These comments received enough positive votes to make them "good answers".

TonyS Guru Join Date: Aug 2010 Location: Resting under the Major Oak Posts: 4347 Good Answers: 181	#1 Re: How do I test Teed protection in one and a half breaker scheme. 12/18/2011 12:56 AM
	What do ABB have to say about testing methods? __________________ The reports of my death are greatly exaggerated.
	Register to Reply

Tornado Guru Join Date: May 2009 Location: Richland, WA, USA Posts: 21017 Good Answers: 795	#2 Re: How do I test Teed protection in one and a half breaker scheme. 12/18/2011 2:08 AM
	What is "half a breaker"? And if so, which half? __________________ In vino veritas; in cervisia carmen; in aqua E. coli.
	Register to Reply

TonyS Guru Join Date: Aug 2010 Location: Resting under the Major Oak Posts: 4347 Good Answers: 181	#3 In reply to #2 Re: How do I test Teed protection in one and a half breaker scheme. 12/18/2011 6:25 AM
	A broken breaker? __________________ The reports of my death are greatly exaggerated.
	Register to Reply

a_chahande Participant Join Date: Nov 2009 Posts: 3	#4 In reply to #2 Re: How do I test Teed protection in one and a half breaker scheme. 12/18/2011 7:19 AM
	'one and half breaker scheme' or 'breaker and half scheme'
	Register to Reply

PWSlack Guru Join Date: Jan 2007 Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on. Posts: 32175 Good Answers: 839	#5 In reply to #4 Re: How do I test Teed protection in one and a half breaker scheme. 12/19/2011 3:40 AM
	Yep. The forum read the words the first time. Repeating them didn't add any meaning to them. __________________ "Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
	Register to Reply

pwr2thepeople Guru Join Date: Aug 2007 Location: Indiana, USA Posts: 579 Good Answers: 61	#6 Re: How Do I Test Teed Protection in One and a Half Breaker Scheme. 12/19/2011 4:34 PM
	Breaker and a half is a very reliable design for electric transmission substations, and in my experience is very common in the electric utility industry, as least in the USA. For those who don't understand, please see page 7 of this document. As for testing the protection systems, we would need more information on the type of protection. What specific types of relays? How are they connected to the CTs and the breaker controls? You say you need to test low and high impedance schemes. Would those be differential (IEEE function type 87) and distance (IEEE function type 21) systems? This type of testing is not something to be done lightly, or without extensive knowledge of protection systems. Improper testing could cause unintentional tripping of related circuit breakers, damage a CT or the test set or even injure test personnel. I know of experienced test engineers inadvertently trip something they needed to keep in service (one time dropping nearly a million customers and costing the company $25 million in fines) because they THOUGHT they knew how the system worked. __________________ Experience: The knowledge you gain just AFTER you needed it.
	Register to Reply Good Answer (Score 2)

These comments received enough positive votes to make them "good answers".

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 (66 right now) Show Members