Electrical Safety Quiz

Testing the RCD with the test button confirms

• Everything is correct with regards to the RCD

• Whether there are any faults in the installation

• Nothing

• Mechanical operation of the RCD

If the line and neutral short together this will result in a fault current to flow; this will be automatically stopped by

• RCD

• MCB or Fuse

• Isolator

• Double pole isolator

When 30mA RCDs are used for fault protection, what is the maximum earth fault loop impedance Zs permitted

• 100 Ω

• 167 Ω

• 1667 Ω

• 500 Ω

Which of these methods are used for establishing Ipf

• Measurement

• Calculation

• Enquiry

• All of the above

What colour BS3036 semi enclosed fuse denotes a 30Amp

• White

• Blue

• Yellow

• Red

Earth leakage current is defined as:

• Electric current appearing in a protective conductor, such as leakage current or electric current resulting from an insulation fault

• An overcurrent occurring in a circuit which is electrically sound.

• Fault of negligible Impedance (Z) between live conductors

• Short circuit or earth fault

What are BS 1362 fuses used for

• High rupturing capacity fuses

• Distributors fuse

• Plug mounted fuse to protect the flexible cord

• Used specifically in industrial applications

Type B- bs60898 Circuit breakers are designed to trip at fault currents:

• 5-10 times the rated current

• 3-5 times the rated current

• 10-20 times the rated current

• 1-3 times the rated current

Which of these best describes an MCB Circuit breaker

• It offers both overcurrent protection and earth fault protection in a single unit

• With most devices, two additional wires must be connected for this device to function

• device shall be provided to break any overcurrent in a circuit before that current could cause danger due to thermal or mechanical effects

• All of the above

What is the breaking capacity of the protective device in the photo