WorksheetsICIT:Quiz on Overview of Protective Devices
Total questions: 20
Worksheet time: 10mins
What is the primary function of a fuse?
To convert AC to DC
To increase current flow
To store electrical energy
To melt and break the circuit under overload
Which part of a fuse is designed to melt when the fuse operates?
Fuse carrier
Fuse base
Fuse element
Fuse link
What type of fuse is designed to protect against heavy overloads?
High Rupturing Capacity (HRC) fuse
Cartridge fuse
Rewirable fuse
Glass fuse
What does the fusing factor indicate?
The maximum current a fuse can carry
The type of material used in the fuse
The speed of operation under fault conditions
The physical size of the fuse
What is the function of an excess current circuit breaker?
To increase voltage in the circuit
To automatically interrupt the circuit under excess current
To provide a constant current
To store energy for later use
Which type of circuit breaker is used as an alternative to fuses?
Miniature Circuit Breaker (MCB)
High Rupturing Capacity Fuse
Residual Current Breaker
Rewirable Fuse
What is the purpose of thermal tripping in an MCB?
To trip the circuit instantly
To provide overload protection over time
To increase the current rating
To reduce the size of the circuit breaker
What does an RCBO combine?
MCB and RCD
Fuse and circuit breaker
HBC fuse and MCB
Fuse and transformer
What is a disadvantage of circuit breakers?
They have no moving parts
They are less reliable than fuses
They are cheaper than fuses
They need regular testing to ensure operation
What is the nominal current rating of an MCB?
The average current in the circuit
The current at which it will trip instantly
The minimum current it can carry
The maximum current it can carry continuously
What is the function of the magnetic tripping mechanism in an MCB?
To trip the circuit under normal conditions
To trip the circuit during overload or short circuit
To provide a constant current
To reduce the size of the circuit breaker
What is the purpose of a blown-out device in a cartridge fuse?
To improve thermal performance
To reduce arcing
To increase the current rating
To indicate when the fuse is blown
What is the main advantage of using circuit breakers over fuses?
They are cheaper
They can be reset after tripping
They are smaller in size
They do not require maintenance
What is the typical current rating range for MCBs?
200A to 400A
100A to 200A
1A to 100A
1A to 5A
What is a common application of residual current devices (RCDs)?
To protect against overloads
To prevent electric shock
To increase circuit capacity
To reduce energy consumption
Which type of circuit breaker is designed to protect against earth faults?
Miniature Circuit Breaker (MCB)
Residual Current Circuit Breaker (RCCB)
Hydraulic Magnetic Circuit Breaker
Air Circuit Breaker (ACB)
What is the primary difference between a fuse and a circuit breaker?
A fuse can be reset, while a circuit breaker cannot
A circuit breaker can be reset, while a fuse cannot
A fuse is more expensive than a circuit breaker
A circuit breaker is used only in residential applications
What is the main purpose of a circuit breaker in an electrical system?
To provide a constant voltage
To interrupt the circuit during overload or fault conditions
To increase the current flow
To store electrical energy
Which type of fuse is typically used in household electrical appliances?
Cartridge fuse
Rewirable fuse
Glass fuse
High Rupturing Capacity (HRC) fuse
What is the role of a surge protector in an electrical circuit?
To increase the voltage
To protect devices from voltage spikes
To reduce current flow
To provide a constant current
