Term
| What insulating materials are best suited for use with high voltage? |
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Definition
| Varnished Cambric and Oil impregnated paper |
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Term
| When a wire is insulated with glass braid or asbestos and requires stripping, what tool should NOT be used? |
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Definition
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Term
| What is the definition of specific resistance? |
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Definition
| The resistance of a unit volume of a substance to the flow of current expressed in Ohms |
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Term
| Why would you use a crimped terminal instead of a wire terminal? |
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Definition
| Connections can be made more rapidly, Less operator skill is required, connections are more uniform in construction |
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Term
| What is an advantage of using preinsulated splices and terminal lugs? |
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Definition
| The offer extra supporting strength to the wire insulation |
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Term
| If a fluorescent light is to be attached to a branch circuit, what type of splice should normally be used? |
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Definition
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Term
| When heat-shrinkable tubing is used, what is the maximum temperature to which the wire should be subjected? |
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Definition
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Term
| When a Western Union splice is used to connect two wires, why should the twisted ends of the wires be pressed down as close as possible to the straight portion of the wire? |
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Definition
| To prevent the wires from puncturing the tape covering |
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Term
| What types of insulation are best suited for use in a high temperature environments? |
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Definition
| FEP, Silicone-rubber, and extruded polytetrafluoroethylene |
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Term
| Plastic insulation is normally used for what level of voltage? |
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Definition
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Term
| When is a rattail joint normally used? |
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Definition
| When a branch circuit is required and a junction box is used to join conduit |
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Term
| When aluminum terminals, lugs, or splices are installed, what tool is generally recommended for use? |
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Definition
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Term
| When a large aluminum terminal or splice is installed, why is it not necessary to clean the aluminum wire? |
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Definition
| Oxide film does not form on aluminum |
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Term
| Why had "unit size" for conductors been established? |
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Definition
| To compare the size and resistance of one conductor to that of another |
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Term
| What is the NEC for a rubber heat resistance compound? |
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Definition
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Term
| What definition best describes an insulating material? |
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Definition
| A material that has a very high resistance |
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Term
| What nonmetallic material is most commonly used to protect wires and cables? |
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Definition
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Term
| Why is friction tape used over a splice? |
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Definition
| To provide a protective covering over the rubber tape |
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Term
| When you work on synthetic insulated wiring, what safety precaution must be observed? |
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Definition
| Avoid breathing in the vapors when the insulation is heated |
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Term
| Why is the use of asbestos being discontinued as an insulating material in the U.S. Navy? |
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Definition
| It poses a health hazard to personnel |
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Term
| What types of conductor protection are normally used for shipboard wiring? |
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Definition
| Wire braid armor and nonmagnetic steel tape |
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Term
| What types of conductor protection are normally used for shipboard wiring? |
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Definition
| Wire braid armor and nonmagnetic steel tape |
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Term
| What is the common name for enamel insulated wire? |
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Definition
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Term
| What are the basic requirements for a splice or terminal connection? |
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Definition
| To be mechanically and electrically effective |
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Term
| What percentage of tin is used in alloy lead sheathing? |
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Definition
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Term
| The most common method of terminating and splicing wires is by using preinsulated terminal lugs and splices. True or False? |
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Definition
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Term
| What is the common name for woven covers? |
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Definition
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Term
| When dealing with NEC type designators for thermoplastics, the letter "W" stands for what type of insulation? |
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Definition
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Term
| When is a knotted tap joint normally used? |
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Definition
| When a branch circuit is joined to a continuous wire (main wire) |
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Term
| Because it's resistance changes very little with temperature changes, what conductor is best suited for use in measuring instruments? |
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Definition
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Term
| When multiconductor cables are spliced, why are the splices staggered? |
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Definition
| To reduce the overall size of the joint |
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Term
| Insulation resistance can best be defined as the ability of an insulating material to resist what action? |
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Definition
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Term
| Latex-rubber is a high grade compound consisting of what percentage of unmilled grainless rubber? |
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Definition
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Term
| When noninsulated terminal lugs and splices are insulated, what types of insulation are most commonly used? |
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Definition
| Spaghetti and heat shrinkable tubing |
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Term
| What type of splice is not butted? |
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Definition
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Term
| Why is a lock washer not used with an aluminum terminal? |
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Definition
| The washer will gouge the lug and cause deterioration |
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Term
| Which metal is a better conductor of current: Copper or Silver? |
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Definition
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Term
| The preferred method for removing insulation from most types of insulated wire is by using what tool? |
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Definition
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Term
| What happens to asbestos insulation when it gets wet? |
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Definition
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Term
| Color codes are used on preinsulated terminal lugs and splices to indicate what information? |
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Definition
| The wire sizes on which they are to be used |
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Term
| The dielectric strength of an insulating material is a measurement of the material's ability to resist electrostatic stress caused by what factor? |
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Definition
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Term
| When a wire gauge is used to determine the size of a wire, the measurement should be made in what part of the gauge? |
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Definition
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Term
| When rubber is used as the insulating material over a copper conductor, why is a thin coating of tin used between the two materials? |
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Definition
| To prevent a chemical action from taking place between the copper and the rubber |
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Term
| What is the preferred tool used to strip aluminum wire? |
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Definition
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