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Milwaukee 49-22-4085 17 Piece Deluxe Electricians' Hole Saw Kit Since its founding in 1924, Milwaukee has focused on a single vision: to produce the best heavy-duty electric power tools and accessories available to professional user. Today, the Milwaukee name stands for the highest quality, durable and reliable professional tools money can buy. This deluxe 17 piece Electricians' Hole Saw Kit has the ultimate range of diameters available. The 12 diameters include: 5/8 inch, 3/4 inch, 7/8 inch, 1 inch, 1-1/8 inch, 1-1/4 inch, 1-3/8 inch, 1-1/2 inch, 1-3/4 inch, 2 inch, 2-1/2 inch, and 3 inch. The kit also includes arbor 49-56-7000 for hole saws up to 1-3/16 inch and arbor 49-56-7140 for hole saws 1-1/4 inch and larger. Additionally the kit has three pilot bits 49-56-8000 and an impact resistant plastic carrying case. The case is also sold separately as 48-55-0784. The hole saws in this kit are of the 6 teeth per inch design. Milwaukee 49-22-4085 17 Piece Deluxe Electricians' Hole Saw Kit Features: • Deluxe assortment of 12 hole saws, two arbors, and three pilot bits • Hole Saws: 5/8 in., 3/4 in., 7/8 in., 1 in., 1-1/8 in., 1-1/4 in., 1-3/8 in., 1-1/2 in., 1-3/4 in., 2 in., 2-1/2 in., 3 in.




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This article originally appeared in Cabling Business Magazine--

NEC Exam Practice Questions-1


By David Herres


National Electrical Code practice exam questions and answers--
National Electrical Code Questions and Answers: Part 1 By David Herres

The National Electrical Code was born in 1896 in response to a rapid increase in the number of electrical fires resulting from new installations like the world's first electrical distribution system in lower Manhattan. Today the National Fire Protection Association creates a new edition every three years. As published, it has no legal standing, but is offered so that states, municipalities and other entities may enact it into law or give it whatever status they wish.

Generally, the Code applies to new building. It is not mandated that existing installations will be upgraded to meet the provisions of each new edition of the Code, but if any renovation is done, that new work must be in compliance in jurisdictions that have enacted the Code.

The Code covers low voltage cabling as well as power and light wiring. Even wiring that does not involve potentially dangerous voltages or power levels is addressed since it can contribute to the spread of fire and toxic smoke generation.

In creating low voltage cabling installations, you should be aware of the on site electrical environments, particularly in regard to grounding and over-current protection, and a good way to start is by becoming familiar with the current edition of the National Electrical Code.

The following Code questions are approximately the same level of difficulty as found on many state electricians’ licensing exams –

1.The purpose of the National Electrical Code is:

A) To provide design specifications for electrical installations.

B) To instruct workers with no previous knowledge in the field.

C) The practical safeguarding of persons and property from hazards arising from the use of electricity.

D) All of the above.

Answer: C) The practical safeguarding of persons and property from hazards arising from the use of electricity.

The Code is concerned with safety and does not address efficiency, convenience or adequacy for future expansion.

2. The NEC covers the installation of electrical conductors, equipment and raceways, signaling and communications conductors, equipment and raceways and optical fiber cables and raceways for the following:

A) Public and private premises, including buildings, structures, mobile homes, recreational vehicles, floating buildings, yards, lots, parking lots, carnivals and industrial substations.

B) Installations of conductors and equipment that connect to the supply of electricity.

C) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops and recreational buildings, that are not an integral part of a generating plant, substation, or control center.

D) All of the above.

Answer: D) All of the above.

Code coverage is spelled out in Article 90.2, Scope.

3. The Code does not cover:

A) Low voltage lighting.

B) Control wiring incapable of giving humans a dangerous shock.

C) Telephone jacks and line cords.

D) Installations underground in mines.

Answer: D) Installations underground in mines.

Underground wiring that is not part of a mine such as lighting in the Lincoln Tunnel is covered.

4. Also not covered in the NEC are installations under the exclusive control of an electric utility where such installations

A) Consist of service drops or service laterals and associated metering.

B) Are located in legally established easements or rights-of-way designated by or recognized by public service commissions, utility commissions or other regulatory agencies having jurisdiction for such installations.

C) Are on property owned or leased by the electric utility for the purpose of communications, metering, generation, control, transformation or distribution of electric energy.

D) All of the above.

Answer: D) All of the above.

Electric utilities are exempt from the NEC but they are governed by the National Life Safety Code plus their own published specifications and procedures.

5. Article 110, Requirements for Electrical Installations, covers:

A) Ampacity of various size and type conductors.

B) General requirements for the examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations.

C) Clearance for overhead conductors and cables.

D) Grounding of motor-operated pumps.

Answer: B) General requirements for the examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations.

Conductors and equipment required or permitted by the NEC are acceptable only if approved. It is up to the Authority Having Jurisdiction, generally an electrical inspector, to make that judgment.

6. In judging equipment, the following considerations are to be evaluated:

A) Cost of the equipment.

B) Electrical insulation.

C) Whether it is copper or aluminum.

D) Place of manufacture.

Answer: B) Electrical insulation.

Suitability of equipment may be evidenced by listing or labeling by Underwriters Laboratory or by one of several similar organizations.

7. Conductor sizes are expressed in:

A) American Wire Gage (AWG) or circular mils.

B) Decimal fractions of an inch.

C) Ounces per foot.

D) Any of these.

Answer: A) American Wire Gage (AWG) or circular mils.

Circular mils measurement is used for sizes larger than 0000.

8. Completed wiring installations must be free of:

A) Short circuits.

B) Ground faults.

C) Any connections to ground other than required or permitted.

D) All of the above.

Answer: D) All of the above.

A short circuit or ground fault may result in very heavy current flow but if the circuit is wired correctly the over-current device will shut it down before damage occurs.

9. Equipment intended to interrupt current at fault levels must have an interrupting rating sufficient for the nominal circuit voltage and current that is available at the line terminals of the equipment.

A) True.

B) False.

Answer: True.

An examination of Ohm’s Law shows that as resistance approaches zero, current approaches infinity. Therefore equipment must be capable of withstanding whatever currents may be available at its input based on source internal impedance.

10. Unless identified for use in the operating environment, no conductors or equipment are to be located in:

A) Damp or wet locations.

B) Where exposed to gases, fumes, vapors, liquids or other agents that have a deteriorating effect on the conductors or equipment.

C) Where exposed to excessive temperatures.

D) All of the above.

Answer: D) All of the above.

During building construction these conditions must be considered and protective measures taken.

11. Where metallic plugs or plates are used to enclose unused openings in nonmetallic enclosures, they are to be:

A) Sealed with silicone.

B) Recessed at least ¼ inch from the outer surface.

C) Flush with the outer surface.

D) None of the above.

Answer: B) Recessed at least ¼ inch from the outer surface.

Closure hardware is available for various sized knockouts, unused breaker positions in entrance panels, and the like, and should always be used where called for.

12. To mount electrical equipment on a concrete wall, the best method is to drive wooden pugs into drilled holes appropriately positioned.

A) True.

B) False.

Answer: B) False.

That method is prohibited by the NEC.

13. Copper to aluminum connections may be made if the device is identified for the purpose and conditions of use.

A) True.

B) False.

Answer: A) True.

When dissimilar metals are in contact and voltage is applied, an electrochemical reaction occurs which results in buildup of oxidized material, a poor conductor, so that heat is generated, sometimes resulting in ignition of any nearby combustible material.

14. Connections of conductors to terminal parts must ensure a thoroughly good connection without damaging the conductors and shall be made by means of:

A) Pressure connectors (including set-screw type).

B) Solder lugs.

C) Splices to flexible leads.

D) Any of the above.

Answer: D) Any of the above.

Connection by means of wire-binding screws or studs and nuts that have upturned lugs or the equivalent is permitted for 10 AWG or smaller conductors.

15. Soldering is _____ an acceptable means of joining conductors.

A) Always.

B) Never.

C) Where specifically permitted.

D) Except where prohibited.

Answer: D) Except where prohibited.

Soldered splices are to be first spliced or joined so as to be mechanically and electrically secure without solder, and then be soldered. All splices and joints and the free ends of conductors are to be covered with an insulation equivalent to that of the conductors or with an insulating device identified for the purpose.

16. The temperature rating associated with the ampacity of a conductor must be selected and coordinated so as not to exceed the lowest temperature rating of any connected termination, conductor or device.

A) True.

B) False.

Answer: A) True.

This requirement is of great importance when designing circuits and choosing conductors.

17. Termination provisions of equipment for circuits rated 100 amperes or less, or marked for 14 AWG through 1 AWG conductors, may be used for:

A) Conductors rated 60 degrees C.

B) Conductors with higher temperature ratings, provided the ampacity of such conductors is determined based on the 60 degree C. Ampacity of the conductor size used.

C) Conductors with higher temperature ratings if the equipment is listed and identified for use with such conductors.

D) Any of the above.

Answer: D) Any of the above.

This requirement should be carefully followed since any misapplication could cause equipment damage or fire hazard.

18. On a four-wire, delta-connected system where the midpoint of one phase winding is grounded, only the conductor or busbar having the higher phase voltage to ground must be durably and permanently marked by an outer finish that is _____ in color or by other effective means.

A) Blue

B) Yellow

C) Orange

D) Black

Answer: C) Orange

This identification is to be placed at each point on the system where a connection is made if the grounded conductor is also present.

19. Field markings warning of arc-flash danger are not required:

A) For other than service equipment.

B) For motor control centers.

C) In dwelling occupancies.

D) For meter sockets.

Answer: C) In dwelling occupancies.

When fed by a source with low internal impedance, arc flash can cause serious injury or death even when the individual does not receive an electric shock.

20. Parts of electrical equipment that in ordinary operation produce arcs, sparks, flames or molten metal must be enclosed or separated and isolated from all combustible material.

A) True.

B) False.

Answer: True.

A metal enclosure used to satisfy this requirement must be grounded to prevent it from becoming energized should an interior fault occur.

21. Where the nominal voltage to ground is 0-150, minimum depth clear working space to the front of an enclosure is:

A) 2 feet.

B) 3 feet.

C) 4 feet.

D) 5 feet.

Answer: B) 3 feet.

Where the voltage is over 150, minimum depths vary depending on presence of live parts or grounded surfaces on one or both sides.

22. The width of working space is _____ inches or the width of the equipment, whichever is greater.

A) 20

B) 24

C) 30

D) 32

Answer: C) 30

It is not necessary for the working space to be centered on the equipment.

23. The minimum headroom of working space about service equipment, switchboards, panelboards or motor control centers is _____ feet or the height of the equipment, whichever is greater.

A) 6

B) 6 ½

C) 7

D 7 ½

Answer: B) 6 ½

In existing dwellings, this rule does not apply to service equipment or panelboards that do not exceed 200 amps.

24. Switchboards, panelboards, distribution boards and motor control centers must have dedicated space equal to the width and height of the equipment and extending from the floor to a height of _____ feet above the equipment or to the structural ceiling, whichever is lower.

A) 4

B) 5

C) 6

D) 8

Answer: C) 6

No piping, ducts, leak protection apparatus, or other equipment foreign to the electrical system may be located in this zone.

25 Electrical equipment rooms in commercial and industrial facilities _____ .

A) May be kept locked.

B) Must not be kept locked.

C) Must have at least one window.

D) Must have unswitched lighting.

Answer: A) May be kept locked.

Electrical equipment rooms or enclosures housing electrical apparatus that are controlled by locks are considered accessible to qualified persons.

-- END --

Next:More NEC practice questions and answers -- NEC Exam 2

Books for electricians --

Here is a selection of the most significant electricians' books available online today, at the best prices around. Clicking on any logo provides access to reviews and ratings by electricians. A good place to start is with the 2008 NEC Handbook, which contains the complete text of the current code plus extensive commentary, diagrams and illustrations. Other books of interest for the electrician are available as well.

Low Voltage, Telecom, Fire Alarm Books --


This site is created and conducted By David Herres, NH Master Electrician License #11335M

E-mail: electriciansparadise@hughes.net


HOME | Best Web Host | Question of the Week | Archived Questions | More Archived NEC Questions | Still More Archived Questions | Still More Archived Questions-2 | Still More Archived Questions-3 | Articles | Electrical Deficiencies | More Electrical Deficiencies | Electricians Tools | Online computers | Cybercorner | Electrician's License | Electronics Tutorials | Electricians' worksaving ideas | Electronic Theorems | Satellite Dish | Digital Cameras and Equipment | HTML Color Chart | Electronic Acronyms | Electronic Definitions | Electrician's Soldering Tutorial | Photovoltaic Power | Wind Power | Fire Alarm Basics | More Fire Alarm Info | Working with MC and EMT | Electricians' Color Code | Wiring Commercial Garages | Managing Your Emergency Lights | Lighting Design | Industrial Wiring | Wiring Ethernet | Residential Wiring | Low Voltage Wiring | PLC Overview | Electrical Troubleshooting Techniques | Using Loop Impedance Meter | Ten Common Grounding Errors |NEC and Low-Voltage Wiring | Raceway Protection and NEC | Working with Metal Raceway | Inductance and Characteristic Impedance | Understanding Capacitance | History of the Ethernet | Twisting Data Conductors | NEC Article 800, Communications Circuits | NEC Article 810, Radio and Television Equipment | NEC Article 820, Community Antenna and Radio Distribution Equipment | NEC Article 830, Network-Powered Broadband | Troubleshooting Submersible Well Pumps | Wiring Healthcare Facilities | First Edition National Electrical Code 1897 | Books for Electricians | Links


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