Electrical Exam Help Quiz

What is the adiabatic equation used to calculate?

• Size of a protective conductor

• Voltage drop

• Cable grouping

• Rating factors

What does the symbol 's' represent in the adiabatic equation?

• Fault current

• Operating time of the fuse

• Cable factor

• Size of the conductor

What is the maximum permitted voltage drop for lighting circuits at 230 volts?

• 9 volts

• 6 volts

• 3 volts

• 12 volts

What does the symbol 'vd' represent in the voltage drop formula?

• Length of the circuit

• Design current

• Millivolts drop

• Actual volts drop

Where can the rating factor tables for various cable conditions be found?

• Page 409

• Page 373

• Page 196

• Page 383

What does the symbol 'i t' represent in the cable size calculation formula?

• Tabulated current

• Breaker size

• Rating factor

• Ambient air temperature

What does the rating factor 'cg' represent in cable grouping calculations?

• Number of cables in a group

• Cable arrangement

• Ambient air temperature

• Derating factor

What is the tabulated current rating for a cable bunched in a group of four in air, protected by a 10 amp breaker?

• 12.5 amps

• 15.38 amps

• 18 amps

• 20 amps

What cable size should be chosen to carry a 20 amp load in a ceiling void, protected by a 10 amp breaker, and bunched in a group of five cables?

• 2.5 millimeter

• 4 millimeter

• 6 millimeter

• 10 millimeter

What is the purpose of the adiabatic equation?

• To determine the maximum permitted voltage drop

• To calculate voltage drop

• To choose a suitable cable size

• To calculate the size of a protective conductor