FREE NCCER Questions and Answers
Without the proper authorization, who is permitted to remove another electrician's tag or lock from any valve, switch, or equipment?
Explanation:
No one is allowed to remove another electrician's tag or lock from any valve, switch, or piece of equipment without proper authorization. This practice ensures safety by preventing unauthorized access to potentially hazardous electrical equipment.
The guardrails in a system can be made from any of the following, EXCEPT:
Explanation:
Rope banding is not suitable for guardrails in construction because it lacks the strength and durability needed to prevent falls. Guardrails are typically made of sturdy materials like pipe, chain, or cable to ensure safety in elevated work areas.
What should be the cable pattern for heating cables used in anti-icing systems?
Explanation:
When installing heating cables for anti-icing systems, the cable pattern should be in a serpentine layout. This layout involves laying the cable back and forth in a series of curves, which ensures even distribution of heat across the surface being heated. It's an effective method for preventing ice buildup and maintaining safe conditions in areas prone to freezing.
What is the angle at which the current leads the voltage in a circuit with pure capacitance?
Explanation:
In a circuit of pure capacitance, the current leads the voltage by an angle of 90-degrees. This phase relationship occurs because the current in a capacitive circuit reaches its maximum value before the voltage does. It's a characteristic feature of capacitive circuits in alternating current (AC) systems.
What is an electrical drawing's revision block's main purpose?
Explanation:
The main purpose of a revision block on an electrical drawing is to note any changes or revisions made to the original drawings. This helps maintain accurate documentation of modifications throughout the project's lifecycle, ensuring that all stakeholders are aware of any updates or alterations to the design.
What is the minimum length required for a UL-listed rod-type grounding electrode?
Explanation:
A UL-listed rod-type grounding electrode must have a minimum length of 8 feet according to the National Electrical Code (NEC). This length ensures proper grounding and safety in electrical systems by providing sufficient contact with the earth to dissipate electrical currents safely.
What is the outer jacket of THWN conductors made of?
Explanation:
THWN conductors have an outer jacket made of nylon. THWN stands for "Thermoplastic Heat and Water-resistant Nylon-coated," indicating that the conductors are insulated with thermoplastic material, and the outer jacket is made of nylon. This combination provides resistance to heat, water, and mechanical damage, making THWN conductors suitable for various electrical applications.
In which of the following drawing locations is the drawing scale MOST likely to be found?
Explanation:
The drawing scale is typically found in the drawing title block. The title block provides important information about the drawing, including its scale, which indicates the ratio between the size of the drawing and the actual size of the object or space being represented. This ensures accuracy and consistency in interpreting the dimensions of the drawing.
What does a sectional drawing depict?
Explanation:
A sectional drawing often depicts a cutaway view of a building, revealing its internal structure and features. It's like slicing through the building to expose its interior details, including walls, floors, and other elements. This type of drawing is useful for understanding the spatial layout and construction of the building.
What is the standard unit used to measure the cross-sectional area of wire?
Explanation:
The standard unit for measuring the cross-sectional area of wire is the circular mil. It represents the area of a circle with a diameter of one mil (1/1000 inch). This unit is commonly used in electrical engineering to specify the size of wires and cables.
How deep must the bare copper conductor in a ground ring be buried, and what is the minimum required length?
Explanation:
The length of a bare copper conductor in a ground ring must be buried no less than 2.5 feet below grade and with a minimum length of 20 feet. This ensures effective grounding and proper dissipation of electrical currents into the earth, maintaining safety in electrical systems.