Answer / mondo

When the secondary of a CT is open circuited, it creates a
very large voltage across the CT. That is why if there is
no burden on the CT, it should always be shorted.

Answer / solanki

one of my frnd says rite that there produced a very high
voltage across the secondary of ct.but from where its
produced no one told.
as all of we know that
E1/E2=I2/I1
FROM THERE E2=E1*I1/I2
BUT IF WE KEEP SECONDARY OPEN THEN I2=0
E2 BECOMES INFNITY

Answer / shashi

If secondary is opened while primary wdg carrying current, then secondary MMF reduce to zero while primary MMF is same.Consequently, the resultant MMF which is equal to primary MMF(as secondary MMF is zero)is very high and it will induce very large flux in the core till core saturates and when this flux links with secondary winding a very high voltage will be induced in secondary wdg .So,
1) This high voltage can breakdown the insulation of secondary wdg.
2) High voltage may even cause fatality to operator who opened the secondary wdg.
3) High resultant flux in core will cause high eddy current loss and hystersis loss .Thus, transformer will get overheated and damage permanently.
4)The high flux will make core permanently magnetised .So, residual flux will introduce error in measuring device.

Answer / shyamsundar nayak

Because there is hevy voltage in secondary........

Answer / yasmina

CT genarally rated as x/5A,orx/1 A as x value depends upon
full load current, CT Volt amp ( rated VA)is constant on
both primary and secondary ,if you kept open the Secondary
a large value of volatge build up and it is hozordious to
equipment around it and operation people.

Answer / mit

> if the secondary of C.T. is open then the secondary mmf
will be reduced.
> this secondary mmf will reduced to primary current. so it's
will create a large flux and the heating will also increase.
> and there is possibilities of shock to user so a C.T. would
never be open circuited.

Answer / ghanshyam singh

it ceases the back emf produced by the secondary of ct
this led to heavy inrush of current through primary as
there is no opposing emf
this may harm the person performing the experiment

What range of speed can you get with the armature control method of speed control of d.c. Shunt motor?

0 Answers  

what is the current law ?

4 Answers   Aster, TCS,

How to design the earth grid for lightning protection in an industry

2 Answers  

WHAT IS DIFFERENCE BETWEEN POTENTIAL DIFFERENCE AND E.M.F?

2 Answers  

what is mean Boost voltage and what is working principle of Tube light

2 Answers   Trimax,

what is the difference between scaler and vector control in drive and where it is to be used ?

1 Answers   Essar, TCS,

if i have 5kw,9A,three phase induction motor,if i want to install it 100 meter away from its feeder,how i will culculate cable size for this load.

2 Answers  

what is ups?how its works?and what is there in static switch how it works?

2 Answers   Bhel,

hi frenz,its aswathy.i hve aplied for the hpcl test on feb,pls send the test patern & the placement papers as soon as possible. mail-id :kjaswathy@gmail.com

0 Answers  

difference between dol and rdol startors?

2 Answers   Vijai Electricals,

Why starters are using the machines???

5 Answers   Alstom,

why open-delta core of 11kv Potential Transformer is 11000v/1.732/110/3?

1 Answers