What is mean CT Saturation? How to calculate?

Answers were Sorted based on User's Feedback



What is mean CT Saturation? How to calculate?..

Answer / ayub

CT saturation is a term used to describe the state wherein
a CT is no longer able to reproduce an output current in
propotional to its primary current or as per its Ratio
The basic reason for CT saturation is due to the property
of the core which goes to magnetic sturation due to number
of reasons like large primary current or high burden at
the secondary or an open circuit in the secondary

The saturation can be found out in the following way
Apply voltage to the secondary windings of CT and gradually
increase the voltage noting down the current . initially
you will find that voltage and current are following a
leniear path and as you increase the voltage you will find
a point where 10% increase in voltage results in 50%
increase in current . This point is practically taken as
saturation point

Is This Answer Correct ?    350 Yes 7 No

What is mean CT Saturation? How to calculate?..

Answer / jai sherring

CT saturates if it is not correcly rated. its ratio has to
be matched to the maximum fault current that it has to
pass. normally the ratio of fault current to rated current
should be kept within 20.
it is very relevant that the fault current is calculated as
per the upstream network fault level. furthe the X/R ratio
of the connecting network needs to be known for calculating
the DC component and its time delay. if the time constant
is small, the saturation shall occur for the first few
cycles, and delaying the actuation will solve the initial
mis-read of current signal. but if the time constant is
large, say of the order of ten cycles, proper sampling
solutions have to be resorted to, that is the current must
be sampled before the onset of saturation.

Is This Answer Correct ?    55 Yes 34 No

What is mean CT Saturation? How to calculate?..

Answer / munwar ali bhand

The CT saturates when we exceed load on CT greater than its VA burden capacity either in case of fault or during testing or normal operation. VA burden depends upon core material of CT used and depends upon B-H curve of the material. These ferromagnetic materials used have ability if they are over excited than they will loose their normal operation properties. in this why if we put more load than its VA capacity of CT than CT will saturate. means that it will not give you accurate results.

Is This Answer Correct ?    16 Yes 3 No

What is mean CT Saturation? How to calculate?..

Answer / faheem

Answer #6 is absolutely right I want to add one thing in it that when once a ct got saturated then it tends to built higher voltage on secondary side then normal due. as normally there is very less voltage on secondary side.

Is This Answer Correct ?    13 Yes 15 No

What is mean CT Saturation? How to calculate?..

Answer / nur.asidik

according to me, almost answers are correct,
in my understanding CT saturation is expressed by knee point voltage for class X, class 5P or 10P CT.

Is This Answer Correct ?    3 Yes 5 No

What is mean CT Saturation? How to calculate?..

Answer / ajit

Now if a ct of the ratio of 5 A / 10 mA and i want 1 v out
put sec voltage, above that it should saturate. Presently
voltage increase up to 3.5 volt.
shall we change the core or no. of turns?

Is This Answer Correct ?    13 Yes 17 No

What is mean CT Saturation? How to calculate?..

Answer / elec engg

#9 and #10 are absolutely confused :D
Secondary in a CT usually has a very High voltage (Primary= 1 Turn; Secondary= Many many Turns).

That`s why, if u leave Secondary open when the CT is Offline, a large voltage build up on the open Secondary causes a failure of its Insulation on Secondary, and renders the CT unoperational/BLOWN !!

Is This Answer Correct ?    2 Yes 9 No

What is mean CT Saturation? How to calculate?..

Answer / lokesh devpura

Ans 6 and 9 are combinely correct. Actually if we want to
check CT saturation that means ouput current must be
correct according to its rating.
And output current is nothing but a voltage across its
secondary which is calculated as its current(like 1V=10A)
i.e. if 1 V output vltg across secondary you find that
means instrument will read 10A current.
So if CT gets saturated then it will read more than 1V and
correspondingly we find false output current.

Is This Answer Correct ?    5 Yes 13 No

What is mean CT Saturation? How to calculate?..

Answer / sumit jha

ct saturation is a condition when the secondary gets open
circuited & so there is no provision of counter balancing
the huge mmf produced due to enormous line current in
primary & so secondary must be connected to the coil of
metering element.& never left open..............

Is This Answer Correct ?    8 Yes 26 No

What is mean CT Saturation? How to calculate?..

Answer / rishit

Sorry to say Mr Kiran Patil if CT is shorted ckted then it
will complete the ckt and save it from any further damage
and meter connected to that CT not able to read current
flowing from that CT.

There are two simple way to calculate the CT saturation
1. There is an instrument operates on 240v,50HZ known as RED
PHASE instrument it is an Australian instrument.
2. Primary injection method in this method we use an
instrument which can only provide current to both of the
primary position of the CT known as P1,P2 and secondary of
that CT are being short ckted so as to calculate the current
and with the help of tong tester we can calculate the
secondary current.

for example we are having CT ratio of 10/5 A and we are
providing primary current of 10 A and from secondary point
we are calculating 5 A current then CT are OK but if we are
getting lesser current than we must say that CT are saturated.

Is This Answer Correct ?    17 Yes 50 No

Post New Answer

More Electrical Engineering Interview Questions

Just a silly question but just to make my curious mind bac to normal - Why was not 67 and 67N relays built into a single relay as i have noticed that the R,Y,B CT wiring end up into the 67 relay while the common of the R,Y,B CT wiring end up into the 67N relay. Then it was better if a single relay was manufactured just like the distance relay (21). Another question i would like to ask is - how do we know where the 67 and 67 N relay has to be placed.why is it not placed at the transformer bay? In the substaion that i am working -i have noticed that it is placed between a breaker and a common double bus bar and this line bay is connected to another substation at a remote place which is furthur connected to a load. B U S______CT for 67 & 67N ______Breaker _____ remot s/s. B A R

1 Answers  


ANY ONE TELL ME ABOUT generator synchronization panel panel to synchronise 3 gen of 250kva both automatic and manual. 2 gen output vol 415 3ph, 1 gen output vol 400 3ph SEND THE DETAILS DIAGRAM ON THIS EMAIL ADDRESS ayazleo@hotmail.com as soon as possilble best ragrds electrical engineer ayaz mahmood SAUDI TECH

0 Answers  


Why efficiency of generator is higher than motor at a particular load?

0 Answers  


What is the required value while doing the megering

1 Answers  


how to find the voltage's of a transmission line plzz help with pictures i am not able to understand

0 Answers   Student,






Given a ckt,the max power dissipated in the load ZL ?

1 Answers  


what is the principle of generator , induction motor,d.c motor

1 Answers  


1)What will happen when 240 VDC supply is connected to 240VAC supply(DC supply +ve is connected to phase of AC supply & DC supply is to neutral of AC supply). 2)Also what will happen when 240 VDC supply is connected to 240 VAC supply in reverse polarity as of Sr. No 1.

2 Answers  


What is d diff. btw MCB & MCCB???

1 Answers   Emerson,


how to find number of run for transformer & alternator secondary side? give the example.

2 Answers   Powergear, Regen Powertech,


what is the speed of the darkness?

3 Answers   Wipro,


if a damaged 500kva transformer with %impedance 2.6 is replaced by two transformers of 250Kva with different % impedance will they be able to catter the load. what will be the ratio of load on the two transformers if the % impedance is in the ratio 1:2

2 Answers   Siemens,


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)