Protective Devices Quiz

At what current level can ventricular fibrillation occur?

• >30mA

• 1mA

• 10-15mA

• 5mA

What color represents a 30A BS 3036 fuse?

• Red

• Blue

• Yellow

• Green

What is the maximum fault capacity of circuit breakers to BS EN 60898?

• 5kA

• 7kA

• 9kA

• 11kA

What is one advantage of BS EN 60898 circuit breakers?

• They are difficult to reset.

• They contain mechanical moving parts.

• Circuit protection is difficult to interfere with.

• They are expensive.

What was the former name for circuit breakers to BS EN 60898?

• Miniature circuit breakers (MCB)

• Large circuit breakers (LCB)

• Standard circuit breakers (SCB)

• Basic circuit breakers (BCB)

What are the two means of tripping for circuit breakers?

• Thermal trip and magnetic tripping device

• Hydraulic trip and pneumatic tripping device

• Electrical trip and mechanical tripping device

• Chemical trip and optical tripping device

What does an RCD compare to detect leakage currents?

• Voltage and resistance

• Current flowing out through the line conductor and returning through the neutral

• Temperature and pressure

• Frequency and amplitude

Which type of circuit breaker is necessary for highly inductive circuits?

• Type 1

• Type 2

• Type C

• Type D

What is an RCBO a combination of?

• A thermal-magnetic circuit breaker and a fuse

• A thermal-magnetic circuit breaker and an RCD

• An RCD and a fuse

• A fuse and a switch

What is the major advantage of using an RCBO?

• It is cheaper than other devices

• It allows earth fault protection to be restricted to a single circuit

• It is easier to install

• It requires no maintenance