Previous in Forum: Can Fire Hydrants Run in Floors (with False Ceilings) Above Cable Trays?   Next in Forum: Earth Drill Machine for Earth Rod
Close
Close
Close
10 comments
Associate

Join Date: Jan 2012
Location: Tema
Posts: 25

Enquiry

03/04/2015 3:57 PM

Hello fellow engineers, please can you help me with some type of tests that are conducted on current transformers.

Thank you

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

Comments rated to be "almost" Good Answers:

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

Join Date: Oct 2008
Posts: 42296
Good Answers: 1663
#1

Re: Enquiry

03/04/2015 4:12 PM

Someone here may help you.

What type of transformers are you testing, and what types of tests are you wishing to perform?

If you can't answer these questions, I'll assume this is a homework (or work related) question.

Then you will be directed to a search engine to look for "transformer tests".

We don't do homework here. Here's a hint: C57.154-2012 - The IEEE Standards Association

Register to Reply
Associate

Join Date: Jan 2012
Location: Tema
Posts: 25
#8
In reply to #1

Re: Enquiry

03/07/2015 8:37 AM

I want to test a current transformer. To confim if its turns ratio (4000/5 amps ) is okay and also a test that will help indicate the polarity of the Current transformer and grounding

Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 15187
Good Answers: 937
#10
In reply to #8

Re: Enquiry

03/07/2015 9:42 AM

Testing the current to voltage transfer of any circuit requires test equipment capable of independently measuring current and voltage. The preferred instrument for these measurements is an oscilloscope with a clamp on current probe and the typical voltage probe that comes with any oscilloscope. If you do not have access to this instrument or if you do not understand how to use it then there is very little we can do to help you.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 15187
Good Answers: 937
#2

Re: Enquiry

03/04/2015 4:24 PM

Two related tests come immediately to my mind. VSWR measurement into an ideal load and insertion loss deviation from ideal transfer.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru

Join Date: Oct 2008
Posts: 42296
Good Answers: 1663
#3

Re: Enquiry

03/04/2015 4:38 PM
Register to Reply
Associate

Join Date: Jan 2012
Location: Tema
Posts: 25
#9
In reply to #3

Re: Enquiry

03/07/2015 8:57 AM

Its not an home work.Its a problem and as a young man am tasked to solve the problem.I was told the problem has been there for 25 yrs and over.I want to solve it-i wil need your views

Register to Reply
Guru

Join Date: Aug 2014
Location: Port Macquarie N.S.W. Australia
Posts: 1071
Good Answers: 225
#4

Re: Enquiry

03/04/2015 6:26 PM

Whichever tests that you decide to do, don't open circuit the secondary while ever there is current flowing through the primary/core.

Register to Reply Score 1 for Good Answer
Guru

Join Date: May 2010
Location: Liverpool, NY
Posts: 960
Good Answers: 131
#5

Re: Enquiry

03/05/2015 10:34 AM

Typical tests on CTs used for instrumentation, control, and protective relaying are a ratio test to verify how close it is to nameplate ratio, and excitation / knee voltage test to verify its saturation point. You could also do an insulation resistance ("megger") test.

__________________
To get the right answers, first you need to ask the right questions.
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 15187
Good Answers: 937
#6

Re: Enquiry

03/05/2015 11:15 AM

The current transformers are tested for lead content and a variety of other toy safety standards.

[Sorry, but I couldn't hold back any longer.]

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Popular Science - Cosmology - New Member Technical Fields - Technical Writing - New Member Engineering Fields - Energy Engineering - New Member Engineering Fields - Electrical Engineering - New Member Engineering Fields - Control Engineering - New Member Engineering Fields - Electromechanical Engineering - Old Member, New Association

Join Date: Apr 2008
Location: Lexington, KY
Posts: 1640
Good Answers: 72
#7

Re: Enquiry

03/05/2015 11:51 AM

Perhaps you are asking how to select an appropriate CT for a given signal. Some CT's are so sensitive that they distort the signal. You may also be interested in frequency response. The problem is that you must know some things about the current you want to monitor in order to select an appropriate CT.

Would you care to elaborate?

__________________
A great troubleshooting tip...."When you eliminate the impossible, whatever remains, however improbable, must be the truth." Sir Arthur Conan Doyle
Register to Reply
Register to Reply 10 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be "almost" Good Answers:

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

Users who posted comments:

KWASI BIMPONG (2); lyn (2); NotUrOrdinaryJoe (1); PeterT (1); redfred (3); spades (1)

Previous in Forum: Can Fire Hydrants Run in Floors (with False Ceilings) Above Cable Trays?   Next in Forum: Earth Drill Machine for Earth Rod

Advertisement