26209 Grounding and bonding

A ground fault is described as an unintentional ____.

• connection between two or more portions of the equipment grounding conductor

• open connection between an electrical circuit or equipment and the earth

• conducting connection between any of the conductors of an electrical system

• electrically conducting connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors

Where a main bonding jumper is required by the NEC®, the jumper cannot be less than what percentage of the area of the largest phase conductor?

• 12.50%

• 14%

• 17.50%

• 20%

A ground test utilizing an auxiliary current electrode and an auxiliary potential electrode is known as the ____.

• one-point test

• three-point tes

• six-point test

• ten-point test

If Single-Gang, Nail-on, nonmetallic boxes are used with NM cable, which of the following is true?

• No connection to the box is required.

• A grounding clip connects the box to the cable.

• Electrical tape connects the box to the cable.

• A standard electrician’s staple connects the box to the cable.

The fall-of-potential method is used to measure ____.

• induced currents

• step voltage

• earth resistance

• touch voltage

Rod, pipe, and plate electrodes must have a resistance to ground of at least ____.

• 25 ohms or less

• 35 ohms or less

• 45 ohms or less

• 75 ohms or less

In a separately derived system, the equipment bonding jumper connects the ____.

• system housing to the neutral bus bar

• system housing to the feeder panel

• neutral on the supply side to the equipment housing

• neutral bus bar to the grounding electrode conductor

Which type of system is required to be grounded?

• Systems less than 50V supplied by grounded transformers

• Circuits for cranes that operate over combustible fibers in Class III locations

• AC systems over 1kV that supply mobile or portable equipment

• Circuits for electrolytic cells

The size of the equipment grounding conductor (EGC) is determined by the ____.

• size of the overcurrent device protecting the system

• length of the conduit

• size of the neutral

• size of the largest conductor

Which of the following is true when installing grounding at more than one building?

• Only the equipment grounding conductor is extended to the second building.

• The second building never requires its own grounding electrode.

• The equipment grounding conductor from the main building is terminated on a bus isolated from the rest of the cabinet.

• The grounded circuit conductor and the equipment grounding conductor must both be extended to the second building.