MCQ
3721. Where severe synchronising swing occur, the relay employed is
Impedance relay
Mho relay
Reactance relay
Induction relay
3722. In sheet metal blanking, shear is provided on punches and dies so that--
press load is reduced
good cut edge in obtained
warping of sheet is minimized
cut blanks are straight
3723. A thermal protection switch can protect against-
Short-circuit
Overload
Temperature
Over voltage
3724. The relay used for feeder protection --
Under voltage relay
Translay relay
Thermal relay
Buchholz relay
3725. An ideal location for the substation would be at ---the of load.
Centre of gravity
Load centre
Nearer to consumer
None of the above
3726. For ground fault we prefer-
Plain impedance relay
Directional over current relay
Mho relay
Reactance relay
3727. The relay used for phase fault protection of short transmission lines is-
Reactance relay
Mho relay
Impedance relay
IDMT relay
3728. In aluminium conductors, steel core is provided to-
compensate for skin effect
neutralise proximity effect
reduce line inductance
increases the tensile strength
3729. The operating speed of a relay depends upon the-
Rate of flux built up
Armature core air gap
Spring tension
All of these
3730. Inverse time current relays are used for the protection of-
Feeders
Transformers
Alternators
Both A and B
3731. In SF6 circuit breakers, the SF, gas-
has insulating properties
is non-inflammable
is non-poisonous
all of the above
3732. A circuit breaker is essentially-
an automatic switch
a manual switch
a high-lightning arrester
none of the above
3733. Factors on which soil resistance depends/RPCI--
depth of the electrode
moisture
Nacl
all the above
3734. Outdoor sub-station requires-space.
Less
More
Medium
Any of the above
3735. For the protection of lines against faults Involving variable fault resistance, the preferred relaying scheme is a-
Plain impedance relay
Directional over-current relay
Mho relay
Reactance relay
3736. Average resistance of human body is-
500 ohms
1000 ohms
1500 ohms
2000 ohms
3737. The main function of a fuse is to-
Protect the line
Open the circuit
Prevent excessive currents
None of the above
3738. Which of the following equipment is used to limit short circuit current level in a sub-station?
Isolator
Lightning switch
Coupling capacitor
Series reactor
3739. The most severe fault on the power system is-
there phase short circuit
line to line fault
double line to ground fault
single line to ground fault
3740. Admittance relay-
Non-directional relay
Directional relay
Differential relay
None of the above