ELECTRICIAN- Earthing MCQ

Prepare for your examinations with a set of multiple choice questions (MCQs) related to Earthing for Electrician Trade. The questions are likely designed to test a user’s knowledge or understanding of electrical concepts and may be useful for exam preparation or self-assessment. The website may be a helpful resource for individuals studying to become electricians or seeking to improve their understanding of electrical principles.

ITI Electrician 

 

EARTHING

What is the minimum size of Copper earth continuity conductor used in single phase domestic wiring as per BIS?3 Sq.mm3.5 Sq.mm2.5 Sq.mm1.5 Sq.mm

Which method is used to reduce earth resistance value in a existing earth?Increasing the length of electrodeKeeping wet condition in earth pits alwaysAdding more sand and charcoal in earth pitsIncreasing the diameter of earth electrode

Why A.C is required to measure the earth resistance by using earth resistance tester?Regulate the currentIncrease the voltage dropDecrease the voltage dropAvoid electrolytic emf interference

What is the formula to find voltage drop of a A.C single phase wiring circuit?Voltage drop = IR voltVoltage drop = I2R voltVoltage drop = I/R voltVoltage drop=IR/2 volt

What is the maximum permissible load for a power sub circuit as per l.E rules?800 Watt1500 Watt2000 Watt3000 Watt

Which location the service connection supply leads to be connected at consumer main board?IC cut outMain switchEnergy meterDistribution board

What is the type of test in domestic wiring installation?

Polarity testContinuity (or) open circuit testInsulation resistance test between conductorsInsulation resistance test between conductors and earth

What is the permissible leakage current in domestic wiring installation?1/5 x Full load current1/50 x Full load current1/500 x Full load current1/5000 x Full load current

Which formula is used to calculate the diversity factor?Diversity Factor = Maximum Load/Installed LoadDiversity Factor = Installed load/Minimum loadDiversity Factor = Minimum actual load/Installed loadDiversity Factor = Installed load/Minimum actual load

Which instrument is used to test new domestic wiring installation?MultimeterMeggerShunt type ohmmeterSeries type ohmmeter

Where system earthing is done?Generating stationElectroplating installationSmall industrial installationDomestic wiring installation

What is the test to be carried out by using megger?Polarity testInsulation resistance testEarth electrode resistance testEarth conductor continuity test

What is the reason of lamp glowing dim and motor running slow in a domestic wiring circuit?Open circuit in the neutral lineShort circuit between conductorsHigh value series resistance faultOpen circuit in the earth conductor

Which wiring installation the System earthing is to be done?SubstationsGodown wiringDomestic wiringCommercial wiring

Which method of earth resistance measurement is illustrated?

Fall of currentFall of potentialCurrent dividingPotential dividing

How to control harmonic distortions in neutral connections as per IE rule?Earthing through impedanceProviding by plate earthingIncreasing conductor sizeProviding parallel earthing

What is the function of current reverser in earth resistance tester?Converts A.C. into D.CReverses the polarity of D.CChanges D.C. supply into A.C supplyReverses the direction of rotation of the generator

What is the advantage of stranded conductor over solid conductor?Cost is lessMore flexibleLess voltage dropMore insulation resistance

How the earth resistance can be reduced?Providing double earthingReducing the pit depth for earthingIncreasing the length of the electrodesDecreasing the length of the electrodes

What is the reason for supplying AC to the electrodes for measuring earth resistance?Provide electrostatic shieldProtect the coils in the meterReduce the value of current in the meterAvoid the effect of electrolytic emf interference

Why the pointer is not stable at zero on the scale as the megger is not in use?It is not having controlling TorqueProvided with air friction dampingThe deflecting torque is directly proportional to the currentThe deflecting torque is directly proportional to the square of the current

Which is proportional for the deflection of ohmmeter needle in earth resistance tester?Current in current coilCurrent in potential coilSpeed of the handle rotationRatio of the current in two coils

Which principle the earth resistance tester works?Self inductionMutual inductionFall of potential methodFleming's left hand rule

Why system earthing is different in utilization than equipment earthing?It protects human onlyIt protects from all circuit faultsIt is associated with current carrying conductorsIt is connected to the non current carrying metal work

What is the effect if a person receives a shock current of 20 mA?No sensationPainful shockHeart convulsionsBecome unconscious

Which electrical equipment L series type MCB's are used?GeysersLocomotivesHalogen lampsAir conditioners

What is the megger reading in a dead short wiring installation?0MW1 MW500 MWInfinity

What is the advantage of crimping?Gives neat appearanceReduce load currentAvoid loose connectionsEasy to replace