Answer / somu0507

The one pole of the CT is earthed to avoid voltages being present due to capacitive coupling between the CT secondary and the line being monitored (CT Primary). At low voltages CT Secondary is not earthed but this is always the case with 11Kv and above.

Answer / paramdeep

CT IS DESIGNED IN SUCH A WAY SO THAT IT ACT AS SET UP TRANSFORMER BUT UNLIKE COMMON TRANSFORMER its secondary current depend upon primary current actauly secondary current balances primary flux if secondary opens. means no secondary current no opposition to primary flux so results in high voltage on secondary side. Which may led core saturation insulation failure

Answer / rajesh mrss

CT SECONDARY SIDE SHORTED BECAUSE OF WHEN WE APPLY HIGH
VOLTAGE ON PRIMARY SIDE FLUX IS GENERATED IF SECONDARY IS
OPEN MEANS FLUX IS INFINITY. THIS PHEONMENON RESULTS
TEMPERATURE RISED SO CT WILL BURSTED SO WE CONNECTED
SECONDARY SIDE TO EARTH

Answer / ali aosar

n LV (low-voltage) installations it is recommended that the
current transformer secondary leads (
S2) are grounded as
protection against static voltages or insulation failure.
Only one connection to ground is necessary and it is general
practice to make this at the transformer. In HV
(high-voltage) installations the current transformers must
be grounded

Answer / d m fulzele

ACTUALLY CT SECONDARY NEVER GROUNDED, CT WHEN CHARGED IT IS LOADED WITH BURDEN OF IT`S SECONDARY SHORT CIRCUITED.
CT IS OPPOSITE TO NORMAL TRANSFORMER. THE PRIMARY CURRENT IS DEPEND ON SECONDARY LOAD CURRENT IN NORMAL TRANSFORMER WHERE AS SECONDARY CURRENT IS DEPEND ON PRIMARY LINE CURRENT. IN CASE OF CT PRIMARY CURRENT IS VERY HIGH. THIS HIGH CURRENT PRODUCES FLUX IN CORE AND THIS HIGH FLUX INDUCES EMF IN SECONDARY WINDING. SINCE THE NUMBER OF TURNS IN SECONDARY ARE MORE, EMF INDUCES IS MORE AND IF SECONDARY IS OPEN THIS HIGH VOLTAGE MAY DAMAGE INSULATION AND CAUSE CT BURST. IF CT SECONDARY IS CONNECTED WITH LOAD OF SHORT CIRCUITED, THE LOAD CURRENT WILL FLOW AND THIS LOAD CURRENT WILL PRODUCES ITS OWN FLUX. THIS FLUX IS OPPOSITE TO MAIN FLUX AND RESULTANT FLUX WILL BE LOW AND HENCE THE EMF INDUCES WILL BE LOW. HENCE IN CT SECONDARY IS ALWAYS SHORT CIRCUITED OF CONNECTED WITH LOAD.

Answer / rohit

to avoid high voltage which is induce when sec. of ct open

Answer / m p

Ct is the stepdown Former, so in primary 220 Kv means we step downing time the voltage ⚡ is infinite, and current is 1 or 5 amps. so ct secondary short means the voltage ⚡ is zero.while the ct secondary is open means the voltage ⚡ is increasing gradually. And suddenly it goes high, then the insulation of ct is failured, then the ct windings are goes to short circuit conditions. At last the ct is borne.

Answer / g.r.raviteja

Current following to low resistance path through the relay ...and corrona effects also .

Answer / anupam a h

CT is basically a step up transformer with primary
connected in series with the load circuit,so thet we can get
a low value of current in the secondary which is
instrumentally measurable.but consequently a high voltage
will be developed in the secondary if sec is left open.to
prevent the high voltage the sec of CT is shirted

Answer / jesudoss

ct secondary dropped the voltage to ground.bcoz if ct sec
short means that fields the primary flux going to oppose
the secondary flux.so the resultant flux is low. suppose
the sec open means secondary side cannot get the flux.the
resultant flux is equal to primary flux .so this flux going
to make high infinite impedence voltage on secondary side.
so this grounding going to prevent from high voltage.

its correct or not?

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