Question 1

A(n) ____ minimum vertical clearance is required above finished grade for sidewalks, or from any platform or projection from which overhead conductors (of 150 volts, or less, to ground) might be reached.

Accepted Answer

According to the National Electric Code (NEC) section 225.19, a minimum vertical clearance of 10-ft (3.0-m) is required above finished grade for sidewalks or any platform or projection from which overhead conductors (of 150 volts or less to ground) might be reached. Therefore, option B is the correct choice.

Question 2

Ground-fault protection that functions to open the service disconnect will afford no protection from faults on the ____ of the protective element.

Accepted Answer

Ground-fault protection that functions to open the service disconnect will only protect against faults on the load side of the protective element. It will not offer any protection for faults occurring on the line side of the protective element.

Question 3

Where the ungrounded supply conductors are larger than 1100 kcmil copper or 1750 kcmil aluminum, the supply-side bonding jumper shall have an area not less than ____ of the area of the largest ungrounded supply conductor or equivalent area for parallel supply conductors.

Accepted Answer

According to NEC 250.102(C), for ungrounded supply conductors larger than 1100 kcmil copper or 1750 kcmil aluminum, the supply-side bonding jumper shall have an area not less than 12.5% of the area of the largest ungrounded supply conductor or equivalent area for parallel supply conductors.

Question 4

According to the NEC, live parts of electric equipment operating at 50 to 1000 volts, nominal, shall be guarded against ____ by approved enclosures.

Accepted Answer

Live parts of electric equipment operating at 50 to 1000 volts, nominal, shall be guarded against accidental contact by approved enclosures, according to the NEC.

Question 5

The alternating current phase arrangement on 3-phase busses are ____ from front to back, top to bottom, or left to right, as viewed from the front of the switchboard, switchgear, or panelboard.

Accepted Answer

The typical phase arrangement on 3-phase busses is A, B, C from left to right or top to bottom as viewed from the front of the switchboard, switchgear or panelboard. This arrangement follows the standard sequence for rotating machines and is commonly used in North America.

Question 6

Vertical wiring clearances apply to ____.

Accepted Answer

Vertical wiring clearances apply to all electrical feeder and service installations.

Question 7

No secondary overcurrent protection is required for certain transformers 1000 volts, nominal, or less with currents of at least 9 amperes and a maximum primary overcurrent protection of ____.

Accepted Answer

The answer of No secondary overcurrent protection is required for...

Question 8

The connection between the grounded circuit conductor (neutral) and the equipment grounding conductor at the service is the ____.

Accepted Answer

The connection between the grounded circuit conductor (neutral) and the equipment grounding conductor at the service is made through the main bonding jumper. This jumper must be sized according to the requirements of the National Electrical Code (NEC) to ensure proper grounding and bonding of the electrical system.

Question 9

Where rear access is required to work on nonelectrical parts at the back of enclosed equipment, a minimum working space of ____ horizontally is required.

Accepted Answer

The National Electrical Code (NEC) specifies that a minimum working space of 30 inches (762 mm) horizontally is required for rear access to work on non-electrical parts at the back of enclosed equipment.

Question 10

According to the NEC, where a panelboard is supplied through a transformer, the overcurrent protection required by 408.36 shall be located on the ____ side of the transformer.

Accepted Answer

The overcurrent protection required by 408.36 (which mandates overcurrent protection for panelboards supplied through transformers) shall be located on the secondary side of the transformer.

Question 11

Equipment rated ____ amperes (or more) and over 6 ft (1.8 m) wide requires an entrance to and egress from the required working space at least 24 in.(610 mm) wide and 6½ ft (2.0 m) high at each end of the working space.

Accepted Answer

According to the National Electrical Code (NEC), equipment rated 1200 amperes or more and over 6 ft wide requires an entrance to and egress from the working space at each end.

Question 12

Overcurrent protection for transformers over ____ volts, nominal, is required.

Accepted Answer

The answer of Overcurrent protection for transformers over ____ volts,...

Question 13

Service equipment in other than dwelling units shall be legibly marked in the field with the ____.

Accepted Answer

Service equipment in other than dwelling units must be marked with the maximum available fault current. This is an important safety consideration, as it allows electrical workers to know the maximum amount of current that could flow in the event of a fault, and to take appropriate precautions when working on the system.

Question 14

A structural ceiling may not ____.

Accepted Answer

Structural ceilings can contain wiring, lighting, and ductwork, but a structural ceiling itself is not a suspended or drop type; those are modifications or additions to the existing structure.

Question 15

A drip loop's lowest point has a minimum vertical clearance of ____.

Accepted Answer

According to the National Electrical Code (NEC), the minimum vertical clearance for a drip loop's lowest point is 10 ft (3.0 m) above grade level or any other reachable surface. This is to prevent water or other liquids from dripping onto the electrical equipment or wiring.

Question 16

The ____ phase must be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems.

Accepted Answer

In a 3-phase, 4-wire, delta-connected system, the phase with the higher voltage to ground is often referred to as the "high leg" or "wild leg" and is traditionally associated with phase B. This configuration is specifically designed to provide both high and low voltages, where phase B, due to its connection in the delta system, carries a higher voltage to ground compared to phases A and C.

Question 17

All panelboards shall have a rating not less than the ____ required for the load calculated in accordance with Part III, IV, or V of Article 220.

Accepted Answer

The rating of the panelboard should be not less than the minimum feeder capacity required for the load calculated in accordance with Part III, IV, or V of Article 220.

Question 18

One access means to a working space is permitted where the location provides ____.

Accepted Answer

Access to a working space should only be permitted where there is a continuous and unobstructed exit available so that workers can safely evacuate the area in case of an emergency. Adequate sprinkler coverage, balcony exits, and overhead clearance are important for other safety concerns but do not necessarily relate to access to a working space.

Question 19

Where ungrounded conductors are increased in size for any reason other than as required in 310.15(B) or 310.15(C), wire-type equipment grounding conductors (where installed) shall be increased in size ____, according to the circular mil area of the ungrounded conductors.

Accepted Answer

When ungrounded conductors are increased in size for any reason other than as required in 310.15(B) or 310.15(C), wire-type equipment grounding conductors (where installed) shall be increased in size proportionately, according to the circular mil area of the ungrounded conductors. This means that the size of the grounding conductor should be increased in direct proportion to the increase in the size of the ungrounded conductor.

Question 20

A ____ is a large single panel, frame, or assembly of panels with front- or rear-mounted switches, protective devices (overcurrent, etc.), buses, and, usually, instruments.

Accepted Answer

A switchboard is defined as a large single panel, frame, or assembly of panels with front- or rear-mounted switches, protective devices (overcurrent, etc.), buses, and, usually, instruments. Panelboard is a similar term, but it refers specifically to panels that distribute power to branch circuits. Circuit cabinet and panel cabinet are not commonly used terms in the electrical industry.

Quiz 14: Services Feeders and Equipment

A(n) ____ minimum vertical clearance is required above finished grade for sidewalks, or from any platform or projection from which overhead conductors (of 150 volts, or less, to ground) might be reached.

Ground-fault protection that functions to open the service disconnect will afford no protection from faults on the ____ of the protective element.

Where the ungrounded supply conductors are larger than 1100 kcmil copper or 1750 kcmil aluminum, the supply-side bonding jumper shall have an area not less than ____ of the area of the largest ungrounded supply conductor or equivalent area for parallel supply conductors.

According to the NEC, live parts of electric equipment operating at 50 to 1000 volts, nominal, shall be guarded against ____ by approved enclosures.

The alternating current phase arrangement on 3-phase busses are ____ from front to back, top to bottom, or left to right, as viewed from the front of the switchboard, switchgear, or panelboard.

Vertical wiring clearances apply to ____.

No secondary overcurrent protection is required for certain transformers 1000 volts, nominal, or less with currents of at least 9 amperes and a maximum primary overcurrent protection of ____.

The connection between the grounded circuit conductor (neutral) and the equipment grounding conductor at the service is the ____.

Where rear access is required to work on nonelectrical parts at the back of enclosed equipment, a minimum working space of ____ horizontally is required.

According to the NEC, where a panelboard is supplied through a transformer, the overcurrent protection required by 408.36 shall be located on the ____ side of the transformer.

Equipment rated ____ amperes (or more) and over 6 ft (1.8 m) wide requires an entrance to and egress from the required working space at least 24 in.(610 mm) wide and 6½ ft (2.0 m) high at each end of the working space.

Overcurrent protection for transformers over ____ volts, nominal, is required.

Service equipment in other than dwelling units shall be legibly marked in the field with the ____.

A structural ceiling may not ____.

A drip loop's lowest point has a minimum vertical clearance of ____.

The ____ phase must be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems.

All panelboards shall have a rating not less than the ____ required for the load calculated in accordance with Part III, IV, or V of Article 220.

One access means to a working space is permitted where the location provides ____.

Where ungrounded conductors are increased in size for any reason other than as required in 310.15(B) or 310.15(C) , wire-type equipment grounding conductors (where installed) shall be increased in size ____, according to the circular mil area of the ungrounded conductors.

A ____ is a large single panel, frame, or assembly of panels with front- or rear-mounted switches, protective devices (overcurrent, etc.) , buses, and, usually, instruments.

Quiz 14: Services Feeders and Equipment

A(n) ____ minimum vertical clearance is required above finished grade for sidewalks, or from any platform or projection from which overhead conductors (of 150 volts, or less, to ground) might be reached.

Ground-fault protection that functions to open the service disconnect will afford no protection from faults on the ____ of the protective element.

Where the ungrounded supply conductors are larger than 1100 kcmil copper or 1750 kcmil aluminum, the supply-side bonding jumper shall have an area not less than ____ of the area of the largest ungrounded supply conductor or equivalent area for parallel supply conductors.

According to the NEC , live parts of electric equipment operating at 50 to 1000 volts, nominal, shall be guarded against ____ by approved enclosures.

The alternating current phase arrangement on 3-phase busses are ____ from front to back, top to bottom, or left to right, as viewed from the front of the switchboard, switchgear, or panelboard.

Vertical wiring clearances apply to ____.

No secondary overcurrent protection is required for certain transformers 1000 volts, nominal, or less with currents of at least 9 amperes and a maximum primary overcurrent protection of ____.

The connection between the grounded circuit conductor (neutral) and the equipment grounding conductor at the service is the ____.

Where rear access is required to work on nonelectrical parts at the back of enclosed equipment, a minimum working space of ____ horizontally is required.

According to the NEC , where a panelboard is supplied through a transformer, the overcurrent protection required by 408.36 shall be located on the ____ side of the transformer.

Equipment rated ____ amperes (or more) and over 6 ft (1.8 m) wide requires an entrance to and egress from the required working space at least 24 in.(610 mm) wide and 6½ ft (2.0 m) high at each end of the working space.

Overcurrent protection for transformers over ____ volts, nominal, is required.

Service equipment in other than dwelling units shall be legibly marked in the field with the ____.

A structural ceiling may not ____.

A drip loop's lowest point has a minimum vertical clearance of ____.

The ____ phase must be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems.

All panelboards shall have a rating not less than the ____ required for the load calculated in accordance with Part III, IV, or V of Article 220.

One access means to a working space is permitted where the location provides ____.

Where ungrounded conductors are increased in size for any reason other than as required in 310.15(B) or 310.15(C) , wire-type equipment grounding conductors (where installed) shall be increased in size ____, according to the circular mil area of the ungrounded conductors.

A ____ is a large single panel, frame, or assembly of panels with front- or rear-mounted switches, protective devices (overcurrent, etc.) , buses, and, usually, instruments.

According to the NEC, live parts of electric equipment operating at 50 to 1000 volts, nominal, shall be guarded against ____ by approved enclosures.

According to the NEC, where a panelboard is supplied through a transformer, the overcurrent protection required by 408.36 shall be located on the ____ side of the transformer.