STED COUNCIL ELECTRICAL QA\QC 2022 SCHEME STED COUNCIL (QA/QC) Online Exam 1 / 50 The algebraic sum of voltages around any closed path in a network is equal to 0 infinity negative polarity 1 2 / 50 Which of the following does not change in an ordinary transformer all of the above Current Voltage Frequency 3 / 50 The frequency of domestic power supply in India is 60 Hz 200 Hz 100 Hz 50 Hz 4 / 50 The wooden poles well impregnated with creosote oil or any preservative compound have life 2 to 5 years 25 to 30 years 60 to 70 years 10 to 15 years 5 / 50 Transmission line insulators are made of P.V.C iron porcelain glass 6 / 50 How much current is produced by a voltage of 18kV across a 15-kilo ohm resistance? 120mA 12mA 1.2A 12A 7 / 50 The filament of electric bulb is made of aluminum carbon tungsten nickel 8 / 50 For which motors DOL starter can be used Up to 15 H.P Up to 10 H.P Up to 20 H.P Up to 5 H.P 9 / 50 Starters are used with D.C motors because 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 10 / 50 What will happen if DC motor is used without starter Depends on load It will start smoothly Heavy sparking at brushes Will not start at all 11 / 50 Form factor for a sine wave is 1.414 1.11 0.637 0.707 12 / 50 Laminated core in electrical machines are used to reduce all of the above hysteresis loss eddy current loss copper loss 13 / 50 H.R.C fuses provide best protection against open circuits short circuits overload reverse current 14 / 50 Sag is independent of None of the above tension in the conductor length of span line voltage 15 / 50 The fuse rating is expressed in terms of VAR voltage current kVA 16 / 50 For 66Kv lines the number of insulator disc are used 2 8 10 6 17 / 50 What is the standard size of GI earth wire in domestic installation 14 SWG 8 SWG 12 SWG 10 SWG 18 / 50 The operating voltage of high-tension cables is up to 11kV 33kV 6.6kV 66kV 19 / 50 Moisture content in the soil earth soil resistance does not affect none of the above increase decrease 20 / 50 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 1200V 120V 21 / 50 Permissible current density of GI 1.2A/mm2 118A/mm2 .28A/mm2 48A/mm2 22 / 50 Power factor of the following circuit will be unity resistance both (a) and (b) capacitance inductance 23 / 50 If the 4 bulbs having power ratings 5W,10W,25W,35W which one will have highest resistance 25W 10W 5W 35W 24 / 50 Size of wire required for a.c 1.5sqm 4sqm 1sqm 2.5sqm 25 / 50 Which type of wiring system is suitable for multistorey building looping out with junction box Tree system Ring main system distribution board system 26 / 50 Who typically performs Factory Acceptance Testing Developers Testers End- users or stakeholders Project Managers 27 / 50 Lamination of transformer core is made up of Aluminum Iron Silicon Steel Steel 28 / 50 The material commonly used for sheath of underground cables is Copper Iron Rubber Lead 29 / 50 A series motor is best suited for driving cranes and hoists none of the above machine tools shear and punches 30 / 50 Transformer ratings are given in kVA HP KW kVAR 31 / 50 A 3-phase 4-wire system is commonly used on Primary distribution Secondary distribution Primary transmission Secondary transmission 32 / 50 Earth wire or ground wire is made up of Copper Iron Al Galvanized steel 33 / 50 Differential relays use the principle of Current magnitude comparison between incoming and outgoing feeder Frequency domain analysis Time domain comparison 34 / 50 Fuse protection is used for current ratings up to 50A 100A 10A 20A 35 / 50 Currently ISO 9001 is going through which revision cycle 2014 2012 2000 2015 36 / 50 The chemical used in breather for transformer should have the quality of cooling the transformer oil absorbing moisture ionizing air cleansing the transformer oil 37 / 50 Relation between phase voltage and line voltage in three phase delta connected system Vline= Vphase Vline= 1.73Vphase Vline= Vphase/1.73 Vline= 1.41Vphase 38 / 50 Which of the following circuit element stores energy in the electromagnetic field variable resistor resistance condenser inductance 39 / 50 Capacitors for power factor correction are rated in kW kV kVAR kVA 40 / 50 A 3phase squirrel cage induction motor is started with star delta starter. What is the starting current of the motor None of the above 1/6 times the current with DOL 3 times the starting current with DOL 1/3 times the current with DOL 41 / 50 How much module box required for a single switch and socket 3m 6m 4m 1m 42 / 50 The voltage of the single-phase supply to residential consumer is 110V 230V 400V 210V 43 / 50 What is the insulation breakdown voltage of a cable 880V 1000V 1100V 1200V 44 / 50 Distribution lines in India generally use R.C.C poles Steel towers None of the above Wooden poles 45 / 50 What is QA it is the measurement of degree to which a product satisfies the need process of identifying defects any systematic process used to ensure quality in the process it is a corrective tool 46 / 50 Sulphur hexafluoride is a semiconductor inactive gas dielectric conductor 47 / 50 The operating voltage of extra high-tension cables is up to 33kV 6.6kV 66kV 11kV 48 / 50 A 3-phase induction motor runs at 1500rpm at no load and 750rpm at full load when connected to 60Hz 3 phase line. Calculate the number of poles the motor has 4 5 2 8 49 / 50 A fuse is connected in series with the circuit in parallel with the circuit either in series or parallel with the circuit none of the above 50 / 50 The speed of a synchronous motor none of the above always remain constant decreases as the load decreases increases as the load increases Your score isThe average score is 66% 0% Restart quiz
