Electrical Exam Help Quiz

What is the adiabatic equation used to calculate?

• Voltage drop

• Size of a protective conductor

• Rating factors

• Cable grouping

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

• Cable factor

• Fault current

• Operating time of the fuse or breaker

• Size of the conductor

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

• 12 volts

• 9 volts

• 6 volts

• 3 volts

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

• Length of the circuit in meters

• Design current of the attached equipment

• Millivolts drop in the cable

• Voltage drop in the circuit

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

• Page 383

• Page 409

• Page 196

• Page 373

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

• Tabulated current

• Tabulated voltage drop

• Tabulated size

• Tabulated cable factor

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

• Ambient air temperature

• Derating factor

• Cable arrangement

• Number of cables grouped together

What is the tabulated current rating for a cable bunched in a group of four in air?

• 19.38 amps

• 17.38 amps

• 15.38 amps

• 13.38 amps

What cable size should be chosen to carry a 20 amp load in a ceiling void at 40 degrees centigrade?

• 10 millimeter cable

• 4 millimeter cable

• 2.5 millimeter cable

• 6 millimeter cable

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

• 3 volts

• 6 volts

• 9 volts

• 12 volts