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