EEP Unit 7

Overcurrent protection for the secondary of a transformer rated 1,000V or less having a secondary current rating of 9A or more must be set at not more than _____ percent of the secondary current rating.

125

The primary overcurrent protection for a transformer rated 1,000V, nominal, or less, having a primary current rating of 9A or more must be set at not more than _____ percent of the primary current when using primary only overcurrent protection.

125

What size secondary conductor can be used for a three-phase, 480V transformer, where the secondary overcurrent protection is sized at 110A?

2 AWG

A 45 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 175A secondary overcurrent device will require at least _____ secondary conductors (the secondary conductors are 10 ft long).

2/0 AWG

What size secondary conductor can be used for a three-phase, 480V transformer, where the secondary overcurrent protection is sized at 175A?

2/0 AWG

The size of the grounding electrode conductor for a single separately derived system must not be smaller than that identified in _____, based on the area of the largest derived ungrounded supply conductor.

250.66

What's the maximum primary overcurrent device rating for a 0.50 kVA, single-phase, 240V transformer?

3 A

A 75 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 300A secondary overcurrent device will require at least _____ secondary conductors (the secondary conductors are 10 ft long).

300 kcmil

In an alternating-current system, the size of the grounding electrode conductor to a concrete-encased electrode isn't required to be larger than a(an) _____ copper conductor.

4 AWG

What's the maximum primary overcurrent device rating for a 2.50 kVA, 480V, single-phase transformer?

6 A

A 45 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 70A primary overcurrent device will require at least _____ primary conductors with terminals rated 75°C.

6 AWG

A 75 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 125A primary overcurrent device will require at least _____ primary conductors with terminals rated 75°C.

6 AWG

What size secondary conductor can be used for a three-phase, 480V transformer, where the secondary overcurrent protection is sized at 50A with terminals rated 75°C?

8 AWG

What's the maximum primary overcurrent device rating for a 25 kVA continuously loaded, three-phase, 240V transformer?

80 A

The connection of the system bonding jumper for a separately derived system must be made _____ on the separately derived system from the source to the first system disconnecting means or overcurrent device.

At any single point

The grounding electrode conductor for a single separately derived system is used to connect the grounded conductor of the derived system to the system bonding jumper.

False