PDX_22_Electrical Part 2

Question 0

Tubes that house, protect, support, and provide grounding for wiring

Answer 0

Conduit

Question 1

Means by which a current is conducted

Answer 1

Conductor

Question 2

Safeguards that allows a current to find an easy path of the earth, eliminating electrical load and protecting people from shock.

Answer 2

Grounding

Question 3

Accidental low resistance connection between two components of an electrical circuit that are meant to be a different voltages.

Answer 3

Short circuit

Question 4

A material of very low conductivity used to separate electrical conductors and prevent leakage of electrical currents

Answer 4

Insulation

Question 5

A device which converts power and one kind of system to power in another form, such as loudspeaker which converts electric power to acoustic power

Answer 5

Transducer

Question 6

Conductor sizes are based onthese two designation systems

Answer 6

American wire gauge (AWG)

And

thousand circular mill (MCM)

Question 7

In the American wire gauge system increasing gauge numbers indicate:

Answer 7

Decreasing wire diameters.

Number 0000 AWG,
Aka 4/0, is largest. Above that MCM Cable sizes of 250, 400, and 500 are used.

Question 8

Circular mill uses this minimum gauge in buildings

Answer 8

Minimum 14 gauge

Question 9

This why are typically requires a special installer. Oxide can form when joints loosen and or overheat. Must be larger than copper to carry amperage. Limited to primary circuits because of overheating. Primarily commercial application.

Answer 9

Aluminum

Question 10

This wire type has the same caring capacity as aluminum but smaller and cheaper. Most cost-effective for small and medium size wire and cable. Primary use is residential and small construction.

Answer 10

Copper wire

Question 11

This cable type requires no conduit. Must be protected from damage within walls. Two or more plastic insulated conductors and ground surrounded by a moisture resistant sleeve. Typically used in residential wood framed buildings less than three stories.

Answer 11

Romex

Question 12

This cable type is flexible metal clad. It has two or more plastic insulated conductors in case in the spiral wound strip of steel tape. No conduit is required and it can easily be pulled. Hence its use in remodels and residential.

Answer 12

Flex metalclad cable (BX)

Question 13

This conductor is a rectangular bar of copper that carries high-voltage. It’s used in place of very large cables and high currents.

Answer 13

Busbar

Question 14

Multiple busbars in a metal housing.

Answer 14

Bus away

Question 15

Primary conduit functions:

Answer 15

Support and protect wiring.
Serves as ground.
Protects surrounding construction from fire in case of overheating.

Question 16

This type of conduit is the safest type. After pipe was installed (indoor/outdoor) wires are pulled through. Connections are rigid and threaded like plumbing pipes. Connect to j-boxes and devices.

Answer 16

Rigid steel

Question 17

This type of steel conduit with Center walls but same outside diameter as rigid. It’s more economical and also used with threaded fittings.

Answer 17

Intermediate metallic conduit

Question 18

This conduit pipe is used everywhere except underground. It reduces vibration transmission from equipment we’re not possible to install rigid.

Answer 18

Flexible metal conduit

Question 19

This conduit type is the thinnest metal. It’s too thin to thread so connections are made with clamps. It’s easy and fast to install but not allowed in hazardous areas.

Answer 19

Electric metallic tubing

Question 20

These are channels for holding electrical wires

Answer 20

Raceways

Question 21

These proprietary steel raceways her cast into concrete floor at regular spacing of 4, 5 or 6 feet.

Answer 21

Underfloor ducts

Question 22

These raceways are part of the structural floor, essentially metal decking used for cable raceways

Answer 22

Cellular metal floors.

Question 23

This thin flat wiring can be laid under carpet without protruding, must be used with carpet tile for ease of access

Answer 23

Under carpet wiring

Question 24

The ratio of average power used to the maximum power demand

Answer 24

Load factor

Question 25

The buildings electrical system is designed to avoid peak electricity use

Answer 25

Load control

Question 26

Switch that is usually magnetically operated used to open and close an electric current

Answer 26

Contactor

Question 27

Set of electrical conductors which extends from the source of energy to a distribution center

Answer 27

Feeder

Question 28

The portion of the buildings electrical system extending from the utility companies wires to and including the main switch and meter

Answer 28

Service

Question 29

Central electrical distribution center that consists of an assembly of switches, circuit breakers and cables or bus ducts that distribute power to the building

Answer 29

Switchgear

Question 30

It component of an electrical supply system which divides and electrical power feed into subsidiary circuit 12 providing a protective fuse or circuit breaker for each circuit, in a common enclosure

Answer 30

Panelboard (breaker box)

Question 31

The insulated wires that run between the outlet and the panel board

Answer 31

Branch circuit

Question 32

Devices used to protect from overload and short-circuiting

Answer 32

Circuit protection

Question 33

Switching device that can make, carry, and break current under normal circuit conditions

Answer 33

Circuit breaker

Question 34

A thin strip of metal that melts and breaks and electrical circuit if the current exceeds the safe level

Answer 34

Fuse

Question 35

Detect small currently and disconnect the hot wire, typically used in kitchens, bathrooms, and outdoor outlets

Answer 35

Ground fault interrupter (GFI)

Question 36

Type of system which mean clued lighting, generators to provide back up our resources in a crisis or when regular systems fail

Answer 36

Emergency power system

Question 37

And electrical apparatus that provides emergency power to a load when the input source fails. Typically used to protect computers, data centers, telecom equipment, or whatever power outage can disrupt business.

Answer 37

Uninterruptible power supply (UPS)

Question 38

Circuit breakers for main disconnects are ____ amps

Answer 38

100 A for main disconnect

Question 39

To account for future expansion, systems should be oversized __%

Answer 39

25%

Question 40

Every circuit has these three wires:

Answer 40

Hot, neutral, and ground wire

Question 41

To avoid the risk of electric shock, it's recommended that appliance housings be grounded to :

Answer 41

A cold water pipe

Question 42

This is typically used on any 15 or 20 amp circuit where water is or might be present. Always within 6 feet of water source.

Answer 42

Ground fault interrupter

Question 43

NEC requires that for single motor installation, the current used in the wire size calculation must be__times the load current from the applicable single phase or three phase tables.

Answer 43

1.25 x the load current

Question 44

Low-voltage switching operates on a__V circuit

Answer 44

24 V circuit

Question 45

And electrically controlled switch used for switching a power circuit, similar to relay but with higher current ratings. Can be remote controlled.

Answer 45

Contactors

Question 46

Raceway as of now become a major architectural consideration that must be addressed early in the design process because of

Answer 46

Computers and networking equipment

Question 47

An outlet where one is always energized, and the other is controlled by switch

Answer 47

Split wire receptacle

Question 48

Typical outlet mounting height above finished floor:

Answer 48

12-18 inches above finish floor 15 inches for ADA

Question 49

Maximum distance between outlets: No point should be further from an outlet then:

Answer 49

12'0" maximum between outlets. no point should be further than 6 feet from an outlet

Question 50

To count as a required power receptacle, floor receptacles must be no further from an exterior wall than

Answer 50

18 inches

Question 51

Minimum circuits required for kitchen counter: Maximum number of outlets per 20 amp circuit in the kitchen:

Answer 51

Minimum of two circuits in the kitchen, No more than four outlets per 20 amp circuit in the kitchen

Question 52

Maximum distance any point on the wall above a counter can be from an outlet:

Answer 52

No greater distance than 24 inches

Question 53

If the building is emergency power supply consist of batteries, they must have a full load capacity of __mins.

Answer 53

90 minutes

Question 54

For the purpose of protecting overall building electrical load, continuous loads should be calculated at__% of their actual value

Answer 54

125% of their actual continuous load value