Switch Gear and Protection Question & Answers February 9, 2023 By Wat Electrical This article lists 100 Switch Gear and Protection MCQs for engineering students. All the Switch Gear and Protection Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up on the fundamentals of Switch Gear and Protection. The switch gear is used for switching, isolation, protection, and control in a power system. The type test, maintenance schedule, acceptance, and commissioning test are the type of tests to be performed on protective gears. In a power system, the surge voltage is caused due to external and internal over-voltage conditions. The measuring relay, fault clearing time, auxiliary relay, relay time, and relay burden are some basic terminologies used in the protection system. The essential features of switchgear are; Complete reliability, absolutely certain discrimination, quick operation, provision for manual control, and instruments . The current transformer, potential transformer, and oil switches come under high voltage switchgear, and air break type switches, isolators come under low voltage switchgear. The switchgear is mainly used in transformer stations, industrial plant factories, distribution substations, paper mills, and so on. The safety of electrical equipment and the safety of human personnel are the operating conditions protection under abnormal. 1). Which one of the following comes under low voltage switchgears? Relays Oil switches Lightning arresters Fuses Hint Read more about Overload relays 2). What is the standard form of CLR? Current Limiting Reluctance Current Limiting Reactor Current Limiting Resistor Current Limiting Resonance Hint 3). Which one of the following comes under potential transformer? Ratio error Phase angle error Shell type Gross error Hint 4). What is the standard form of ACB? Air Circuit Breaker Air Control Breaker Air Common Breaker Armature Circuit Breaker Hint 5). What are the advantages of oil circuit breaker? Slower operation Highly inflammable Easily available Uses less quantity of oil Hint 6). The low voltage range of switch gear is up to _______________? 11 KV 66 KV 400 KV 765 KV Hint 7). Which one of the following performs both detection and interruption functions? Circuit breaker Fuse Air circuit breaker Oil switches Hint 8). Which one of the following requires replacement after every operation? Fuse Circuit breaker Oil switches Lightning arresters Hint 9). ________________ are the applications of low voltage switch gear? Motor unit protection Capacitors Both a and b None of the above Hint Read more about Capacitors 10). What is the standard form of BOCB? Bulk Oil Circuit Breaker Beaker Oil Circuit Bulk Bulk Oil Common Breaker Bulk Oil Controller Breaker Hint Read more about Switch Gear components. 11). Which one of the following arresters can be done outside of the panel board? Surge arrester Lightning arrester Regulators Fuses Hint 12). What is the standard form of TVSS? Transient Voltage Surge Suppressor Transient Voltage Single Suppressor Transient Voltage Simple Suppressor Transformer Voltage Simple Suppressor Hint 13). What are the essential features of switch gear? Complete reliability Provision for instruments Provision for manual control All of the above Hint Read more about Switchgear 14). Which one of the following comes under switching devices? Isolators Current transformers Regulators Commutators Hint 15). What are the disadvantages of oil circuit breaker? High maintenance cost Low cost Easily available All of the above Hint 16). What is the standard form of MCCB? Moulded Case Circuit Breaker Moulded Case Control Breaker Moulded Case Common Breaker Moulded Case Controller Breaker Hint 17). Which one of the following used as an ON/OFF switch? Fuse Circuit breaker Lightning arresters Oil switches Hint 18). What is the standard form of IDMT? Internal Definite Minimum Time Infinite Definite Minimum Time Inverse Definite Minimum Time Identical Definite Minimum Time Hint 19). The high voltage range of switch gear is up to _______________? 11 KV 66 KV 400 KV 765 KV Hint 20). What is the standard form of MOCB? Minimum Oil Circuit Breaker Main Oil Circuit Beaker Multi Oil Circuit Breaker Hint 21). Which one of the following is an example of principal switchgear? Fuses Circuit breakers Protection relays Regulators Hint Read more about Fuse & Types 22). What is the standard form of MDB? Main Distance Board Main Difference Board Main Distribution Board Main Displacement Board Hint Read more about Isolator 23). Which one of the following comes under symmetric fault? L-L-L-G L-G L-L None of the above Hint 24). What are the effects of electrical faults? Over current flow Loss of equipment Electrical fires All of the above Hint 25). Which one of the following comes under high voltage switchgears? Relays Fuses Current transformer Oil switches Hint Switchgear and Protection MCQ for Quiz 26). What is the standard form of MCB? Main Circuit Breaker Moulded Control Breaker Miniature Circuit Breaker Main Circuit Board Hint 27). In which one of the following the breaking capacity is very large? Circuit breaker Fuse Oil switches Relays Hint 28). Which one of the following comes under control and sensing devices? Switches Voltage transformers Regulators Commutators Hint 29). What are the causes of an electrical faults? Over current flow Loss of equipment Smoke of fires None of the above Hint 30). __________________ are the components of digital relay? Multiplexer and S/H circuits Anti-aliasing filters Event storage system All of the above Hint 31). What is the standard form of RCCB? Residual Current Circuit Breaker Residual Current Control Breaker Residual Current Common Breaker Residual Current Commutator Breaker Hint 32). Which one of the following comes under unsymmetric fault? L-L-L-G L-G LL-G None of the above Hint 33). Which one of the following is an on-load device? Isolator Circuit breaker Regulator Transformer Hint 34). Which one of the following has better capabilities? Isolator Circuit breaker Fuses Relays Hint 35). What is the standard form of HRC? High Rupturing Capacity High Rupturing Controller High Rupturing Commutator High Regulator Capacity Hint 36). Which one of the following requires tripping circuit? Isolator Circuit breaker Insulator Regulator Hint 37). In which one of the following, the periodic maintenance is very much required? Isolator Circuit breaker Insulator Regulator Hint 38). What is the standard form of SAW? Submerged Arc Welding Single Arc Welding Simple Arc Welding Structural Arc Welding Hint 39). _____________ are the qualities of protective relay? Selectivity Speed Sensitivity All of the above Hint 40). What is the standard form of VCB? Vacuum Commutator Breaker Vacuum Controller Breaker Vacuum Circuit Breaker Voltage Commutator Breaker Hint 41). In which one of the following no auxiliary contact is required? Fuse Circuit breaker Insulator Regulator Hint 42). Which one of the following comes under decision making devices? Switches Isolators Lightning Relays Hint 43). What is the standard form of SDB? Single Distribution Board Simple Distribution Board Sub Distribution Board Sectional Distribution Board Hint 44). Which one of the following has arcing contact and main contact? Isolator Circuit breaker Relays Regulators Hint 45). What is the standard form of SF6CB? Sulphur Hexafluoride Commutator Breaker Sulphur Hexafluoride Controller Breaker Sulphur Hexafluoride Circuit Breaker Sulphur Hexafluoride Commutator Board Hint 46). Which one of the following operating times is very small? Circuit breaker Fuse Relays Surge arrester Hint 47). Which one of the following is an example of auxiliary switchgear? Fuses Isolators Circuit breakers Regulators Hint 48). Which one of the following occupies more space? Isolator Circuit breaker Surge arrester Lightning arrester Hint 49). What is the standard form of GMAW? Gas Metal Arc Welding Group Main Arc Welding Gas Metal Welding Gas Metal Armature Welding Hint 50). What is the standard form of ABCB? Air Blast Commutator Breaker Air Blast Controller Breaker Air Blast Circuit Breaker Armature Blast Commutator Breaker Hint Switchgear and Protection MCQ for Interviews 51). The _____________ relay is based on actuating parameter? Static relay Mechanical relay Current relay Latching relay Hint 52). The ________________ relay is based on operation of mechanism? Current relay Voltage relay Static relay Latching relay Hint 53). What is the standard form of FACTS? Flexible AC Transmission System Flexible AC Transient System Flexible AC Transformer System Flexible Armature Transmission System Hint 54). What is the standard form of SVC? Static VAR Controller Static VAR Compensator Static VAR Commutator Simplex VAR Compensator Hint 55). Which one of the following is a type of distance relay? Reactance relay Balanced beam relay Induction disc relay Latching relay Hint 56). What is the standard form of LBS? Line Breaking Switch Load Breaking Switch Load Breaking Signal Load Board Switch Hint 57). In which one of the following operating times is from 0.1 to 0.2 sec? Circuit breaker Fuse Relay Regulator Hint 58). What is the standard form of ATS? Automatic Transformer Switch Automatic Transfer Switch Automatic Transient Switch Armature Transfer Switch Hint 59). What is the standard form of STATCOM? Static Synchronous Compensator Synchronous Static Compensator Static Synchronous Commutator Static Synchronous Controller Hint 60). Which one of the following is a type of electromagnetic relay? Reactance relay Balanced beam relay Quadrilateral relay Machine tool relay Hint 61). Which one of the following doesn’t give any indication? Fuse Circuit breaker Machine tool relay Contactor Hint 62). What is the standard form of ELCB? Earth Leakage Control Breaker Earth Leakage Commutator Breaker Earth Leakage Circuit Breaker Earth Line Control Breaker Hint 63). Which one of the following is a best modelled by magnetic breakers? Instantaneous over current relay protection Time over current relay protection Both a and b None of the above Hint 64). What is the standard form of SMAW? Shielded Metal Arc Welding Shielded Main Arc Welding Single Metal Arc Welding Hint 65). Which one of the following circuit breakers used for medium capacities? BOCB ABCB GFCI AFCI Hint 66). Which one of the following is a safety isolation device? Isolator Circuit breaker AFCI Mercury-wetted relay Hint 67). In which one of the following relays the multifunction's are possible? Microprocessor based Electro-mechanical Both a and b None of the above Hint Read more about Distance Relay 68). In which one of the following relays, the blocking feature is not available? Electro-mechanical Microprocessor based Mercury-wetted relay Mercury relay Hint 69). What is the standard form of FCAW? Flux Control Arc Welding Flux Common Arc Welding Flux Cord Arc Welding Flexible Control Arc Welding Hint 70). In which one of the following circuit breakers, the reliability is less? BOCB ABCB GFCI AFCI Hint 71). The extra high voltage range of switch gear is up to _______________? 11 KV 66 KV 400 KV 765 KV Hint 72). What is the standard form of MPCB? Motor Protection Circuit Breaker Motor Protection Control Breaker Motor Protection Commutator Breaker Main Protection Circuit Breaker Hint 73). Which one of the following is a normal circuit protector? Isolator Circuit breaker Relays Fuses Hint 74). What is the standard form of ECM? Electro Chemical Meter Electro Chemical Method Electro Chemical Machining Electro Controller Meter Hint 75). In which one of the following circuit breakers the endurance is below average? Vacuum breakers Oil breakers Air breakers Residual Current Circuit Breaker Hint Switchgear and Protection MCQ for Exams 76). What is the standard form of EBM? Electrical Beam Meter Electron Beam Motor Electron Beam Machining Electrical Board Meter Hint 77). The heat input is high per unit length in ____________ type of welding? Arc Laser Hybrid FCAW Hint 78). The welding speed is low in _______________ type of welding? Arc Laser Hybrid FCAW Hint 79). What is the standard form of GTAW? Gas Tungsten Arc Welding Gas Tungsten Aim Welding Gas Tungsten AM Welding Gas Tungsten Armature Welding Hint 80). Which one of the following circuit breakers sizes is quite large? Vacuum breakers Oil breakers Air breakers GTAW/TIG Hint 81). What is the standard form of HBC? High Breaking Control Fuse High Breaking Commutator Fuse High Breaking Current Fuse High Breaking Common Fuse Hint 82). Which one of the following has moving blades/alarm and main contact? Isolator Circuit breaker Mercury relay Multi-voltage relays Hint 83). The arc quenching techniques provided in ________________? Isolator Circuit breaker Machine tool relay Coaxial relay Hint 84). Which one of the following operated automatically or manually? Isolator Circuit breaker Coaxial relay Contactor Hint 85). What is the standard form of HVCB? High Voltage Commutator Breaker High Voltage Controller Breaker High Voltage Circuit Breaker High Voltage Common Breaker Hint 86). Which one of the following is a best modelled by thermal breakers? Instantaneous over current relay protection Time over current relay protection Both a and b None of the above Hint 87). The flags, targets are the visual indications in ______________ relays? Electro-mechanical Microprocessor based Both a and b None of the above Hint 88). In which one of the following relays the self-supervision feature is available? Electro-mechanical Numerical relays Latching relay Machine tool relay Hint 89). The speed of operation is low in ________________ relay? Electro-mechanical Numerical relays Machine tool relay Mercury relay Hint 90). What is the standard form of LVSD? Less Voltage Switch Devices Line Voltage Switch Devices Low Voltage Switchgear Devices Low Volume Switchgear Devices Hint 91). The range of settings is wide in _________________ relay? Electro-mechanical Microprocessor based Latching relay Machine tool relay Hint 92). In which one of the following relays the communication feature is not available? Electro-mechanical Microprocessor based Latching relay Machine tool relay Hint 93). The consistency of calibration is deteriorate with time in ________________ relay? Electro-mechanical Numerical relays Latching relay Machine tool relay Hint 94). Which one of the following relays is not adaptable? Numerical relays Electro-mechanical Contactor Coaxial relay Hint 95). What is the standard form of HVS? High Voltage Switches High Voltage Signals High Voltage Sample High Volt-ampere Switches Hint 96). The medium voltage range of switch gear is up to _______________? 11 KV 66 KV 400 KV 765 KV Hint 97). The LEDs, LCD are the visual indications in ______________ relays? Electro-mechanical Microprocessor based Both a and b None of the above Hint 98). What is the standard form of EDM? Electrical Discharge Meter Electro Discharge Method Electro Discharge Machining Electro Discharge Multimeter Hint 99). Which one of the following found in an electrical distribution and generation stations such as yards? Isolator Circuit breaker Fuses Regulator Hint 100). What is the standard form of HVF? High Voltage Fission High Voltage Fusion High Voltage Fuses High Volt-ampere Fuses Hint For more MCQs refer toIsolator MCQ's Time's up
