NCCER 209 Exam QUESTIONS AND CORRECT
ANSWERS
The fall-of-potential method is used to measure _____. - CORRECT ANSWER earth
resistance
Which of the following is TRUE when installing grounding at more than one building? -
CORRECT ANSWER The grounded circuit conductor and the equipment grounding
conductor must both be extended to the second building.
The key to successfully clearing ground fault currents is _____. - CORRECT
ANSWER electrical continuity
The bonding jumper for multiple disconnecting means is located _____. - CORRECT
ANSWER on the supply side of the service disconnect
A transformer bonding jumper is routed with the feeder conductors from the transformer to
the equipment grounding bar in the panel and is known as a(n) _____. - CORRECT
ANSWER supply-side bonding jumper
When a new grounding system has been installed, it is advisable to conduct baseline three-
point tests every _____. - CORRECT ANSWER season for the first year
A transformer-supplied system operating at less than 50V must be grounded if the supply
voltage to the transformer exceeds _____. - CORRECT ANSWER 150V to ground
A ground tester can be used to measure the value of a grounding electrode's _____. -
CORRECT ANSWER resistance
The size of the equipment grounding conductor is determined by the size of the _____. -
CORRECT ANSWER system overcurrent device
ANSWERS
The fall-of-potential method is used to measure _____. - CORRECT ANSWER earth
resistance
Which of the following is TRUE when installing grounding at more than one building? -
CORRECT ANSWER The grounded circuit conductor and the equipment grounding
conductor must both be extended to the second building.
The key to successfully clearing ground fault currents is _____. - CORRECT
ANSWER electrical continuity
The bonding jumper for multiple disconnecting means is located _____. - CORRECT
ANSWER on the supply side of the service disconnect
A transformer bonding jumper is routed with the feeder conductors from the transformer to
the equipment grounding bar in the panel and is known as a(n) _____. - CORRECT
ANSWER supply-side bonding jumper
When a new grounding system has been installed, it is advisable to conduct baseline three-
point tests every _____. - CORRECT ANSWER season for the first year
A transformer-supplied system operating at less than 50V must be grounded if the supply
voltage to the transformer exceeds _____. - CORRECT ANSWER 150V to ground
A ground tester can be used to measure the value of a grounding electrode's _____. -
CORRECT ANSWER resistance
The size of the equipment grounding conductor is determined by the size of the _____. -
CORRECT ANSWER system overcurrent device
