STED COUNCIL ELECTRICAL QA\QC 2022 SCHEME 0% STED COUNCIL (QA/QC) Online Exam Your NameEmail-idPhone Number 1 / 50 1) The operating voltage of extra high-tension cables is up to 6.6kV 11kV 33kV 66kV 2 / 50 2) Pin type insulators are not used for voltages beyond 22kV 1kV 33kV 11kV 3 / 50 3) Factors on which soil resistance depends all of the above moisture salt depth of electrode 4 / 50 4) The primary winding of a transformer has a 120V ac supply. What is the value of secondary voltage if the turns ratio is 10 12000V 12V 120V 1200V 5 / 50 5) Sulphur hexafluoride is a conductor dielectric semiconductor inactive gas 6 / 50 6) Starters are used with D.C motors because These motors are not self-starting Back emf of these motors is initially zero These motors have high starting torque To restrict armature current as there is no back emf while starting test wrong answer test right answer 7 / 50 7) In a cable immediately above, metallic sheath _______ is provided none of the above armouring bedding earthing connection 8 / 50 8) In which of the following motors the stator and rotor magnetic field rotate at the same speed induction motor synchronous motor universal motor reluctance motor 9 / 50 9) Overhead system can be designed for operation up to 33kV 11kV 66kV 400kV 10 / 50 10) How much current is produced by a voltage of 18kV across a 15-kilo ohm resistance? 12A 12mA 120mA 1.2A 11 / 50 11) A series motor is best suited for driving machine tools cranes and hoists none of the above shear and punches 12 / 50 12) The operating voltage of high-tension cables is up to 11kV 6.6kV 33kV 66kV 13 / 50 13) The chemical used in breather for transformer should have the quality of cooling the transformer oil cleansing the transformer oil absorbing moisture ionizing air 14 / 50 14) The insulating material of a cable should have low-cost high mechanical strength all of the above high dielectric strength 15 / 50 15) Capacitors for power factor correction are rated in kVA kV kVAR kW 16 / 50 16) The frequency of domestic power supply in India is 60 Hz 50 Hz 100 Hz 200 Hz 17 / 50 17) 3-point starter is used to start the Both (b) and (c) compound motor shunt motor series motor 18 / 50 18) Which of the following does not change in an ordinary transformer all of the above Current Frequency Voltage 19 / 50 19) The voltage of the single-phase supply to residential consumer is 230V 400V 110V 210V 20 / 50 20) For which motors DOL starter can be used Up to 20 H.P Up to 5 H.P Up to 15 H.P Up to 10 H.P 21 / 50 21) The filament of electric bulb is made of nickel carbon tungsten aluminum 22 / 50 22) The material commonly used for sheath of underground cables is Lead Rubber Copper Iron 23 / 50 23) Relation between phase voltage and line voltage in three phase delta connected system Vline= Vphase/1.73 Vline= Vphase Vline= 1.41Vphase Vline= 1.73Vphase test wrong answer test right answer 24 / 50 24) Form factor for a sine wave is 0.637 1.414 0.707 1.11 25 / 50 25) Which type of wiring system is suitable for multistorey building Ring main system distribution board system looping out with junction box Tree system 26 / 50 26) Permissible current density of GI These motors are not self-starting These motors have high starting torque To restrict armature current as there is no back emf while starting Back emf of these motors is initially zero test wrong answer test right answer 27 / 50 27) Differential relays use the principle of Frequency domain analysis Current magnitude comparison between incoming and outgoing feeder Time domain comparison 28 / 50 28) In an induction motor, rotor slots are usually not quite parallel to the shaft but are given a slight skew To reduce the magnetic hum Both (a) and (b) To reduce the locking tendency of the rotor To increase the speed of the rotor 29 / 50 29) What is the insulation breakdown voltage of a cable 1100V 1000V 1200V 880V 30 / 50 30) Fuse protection is used for current ratings up to 50A 100A 10A 20A 31 / 50 31) The fuse rating is expressed in terms of current kVA VAR voltage 32 / 50 32) Power factor of the following circuit will be unity capacitance inductance both (a) and (b) resistance 33 / 50 33) Breaking capacity of a circuit breaker is usually expressed in terms of MW MVA volts amperes 34 / 50 34) H.R.C fuses provide best protection against open circuits reverse current short circuits overload 35 / 50 35) Transmission line insulators are made of iron porcelain P.V.C glass 36 / 50 36) A fuse is connected none of the above either in series or parallel with the circuit in series with the circuit in parallel with the circuit 37 / 50 37) The algebraic sum of voltages around any closed path in a network is equal to 0 infinity 1 negative polarity 38 / 50 38) A 3-phase 4-wire system is commonly used on Primary distribution Primary transmission Secondary distribution Secondary transmission 39 / 50 39) Transformer ratings are given in kVAR kVA KW HP 40 / 50 40) The medium employed for extinction of arc in air circuit breaker is vacuum air SF6 oil 41 / 50 41) The field coils of D.C generator are made of copper mica carbon cast iron 42 / 50 42) For 66Kv lines the number of insulator disc are used 6 8 2 10 43 / 50 43) Distribution lines in India generally use None of the above R.C.C poles Steel towers Wooden poles 44 / 50 44) Which of the following circuit element stores energy in the electromagnetic field resistance condenser inductance variable resistor 45 / 50 45) Laminated core in electrical machines are used to reduce hysteresis loss copper loss all of the above eddy current loss 46 / 50 46) What will happen if DC motor is used without starter Depends on load It will start smoothly Will not start at all Heavy sparking at brushes 47 / 50 47) The speed of a synchronous motor always remain constant none of the above increases as the load increases decreases as the load decreases 48 / 50 48) The conductors of the overhead lines are Stranded Solid None of the above Both (a) and (b) 49 / 50 49) What is the standard size of GI earth wire in domestic installation 8 SWG 12 SWG 14 SWG 10 SWG 50 / 50 50) Moisture content in the soil _______ earth soil resistance increase does not affect decrease none of the above Your score is 0%
