PROPERTY & BUILDING INSPECTION MODULE 2

Question 1

Ampacity

Answer 1

the maximum current that a conductor or device may carry continuously without exceeding its temperature rating.

Question 2

AWG

Answer 2

the abbreviation for American Wire Gauge, a system for identifying the diameter of electrical wires; larger numbers identify smaller diameter wires; #14 (pronounced number 14 or 14 gauge) is the smallest wire used in house wiring, and 4/0 (pronounced four-oh) is usually the largest.

Question 3

Bonding

Answer 3

the process of connecting, both physically and electrically, metal components of the electrical system that are not intended to carry electrical current to provide a low resistance return path to the circuit breaker or fuse to clear ground faults; bonding is an electrical safety system.

Question 4

Branch circuit

Answer 4

conductors that begin at a circuit breaker or fuse and serve one or more outlets.

Question 5

Branch circuit, multi-wire

Answer 5

a branch circuit in which two energized conductors share one neutral conductor; examples can include clothes dryers, ranges and other cooking appliances, and split-wire receptacle circuits; 240 volt water heaters and condensers for air conditioners and heat pumps are not usually multi-wire branch circuits.

Question 6

Bus

Answer 6

the heavy, rigid metal part of a panelboard on which circuit breakers or fuses are mounted; sometimes used to describe metal terminals to which the neutral and equipment grounding conductors (EGCs) are connected.

Question 7

Cable

Answer 7

two or more conductors encased in sheathing; examples include non-metallic sheathed cable (often referred to by the brand name Romex) and armored cable (often referred to by the brand name BX).

Question 8

Conductor

Answer 8

a material, such as copper or aluminum, that permits electricity to flow with low resistance; wires are conductors.

Question 9

Current

Answer 9

the amount of electricity in a circuit; (similar to water gallons per minute; water flow in a pipe); unit of measure is the Ampere (Amp); expressed as I in Ohm’s Law and Watt’s Law equations

Question 10

Dead front cover

Answer 10

a panel that is removed to gain access to the energized components inside an enclosure; the dead front cover is usually behind a door that must be swung or lifted to gain access to the dead front cover.

Question 11

Enclosure (electrical)

Answer 11

a case or cabinet intended to prevent accidental contact with energized parts; a panelboard is housed inside an enclosure.

Question 12

Feeder conductors

Answer 12

conductors from the service equipment or from a panelboard that supply electricity to another panelboard such as a subpanel.

Question 13

Grounded

Answer 13

a conductor that is intentionally connected to the earth; this describes what is often called the neutral conductor.

Question 14

Grounding

Answer 14

providing an intentional connection to the earth; grounding provides an alternate path for current to return to its source; in an electrical power system, the source is the utility’s transformer and ultimately the power plant. See Grounding electrode and Grounding electrode conductor (GEC).

Question 15

Grounding conductor, equipment (EGC)

Answer 15

a bare or green insulated conductor that provides a ground fault current path (a bonding connection) for equipment with metal cases and parts; these have been installed in most house branch circuit wiring since around 1960.

Question 16

Grounding electrode

Answer 16

metal that is in direct contact with the earth and serves as the electrical system grounding connection; examples include copper-coated steel rods, galvanized steel pipes, water service and well pipes, and reinforcing steel encased in the footings.

Question 17

Grounding electrode conductor (GEC)

Answer 17

a conductor that runs between the grounding electrode and an accessible point downstream from where the grounded service entrance conductor connects to the service drop or lateral; the GEC connection is usually at the service equipment.

Question 18

Ground fault

Answer 18

an event that occurs when metal that should not conduct electricity (such as a metal water pipe) becomes energized; if the metal is properly bonded, current flow should increase in the circuit and trip the circuit breaker or fuse.

Question 18

Knockouts

Answer 18

stamped openings in an enclosure where conduit or cable clamps are installed to secure conductors or cables. See Tabs (twistouts)

Question 19

Ohm’s Law and Watt’s Law

Answer 19

expressions of the relationship between current, volt-age, power, and resistance; expressed as Power = Volts X Amps and Resistance = Volts/ Amps.

Question 19

Joules Law

Answer 19

a formula for calculating heat in an electrical circuit expressed as Heat = Current2 X Resistance X Time

Question 19

Lug

Answer 19

a connection point where conductors are inserted and secured; examples include the connection points on panelboards for service entrance and feeder conductors, on terminal bars for neutral and EGCs, and on circuit breakers for branch circuit conductors.

Question 19

Ground fault circuit interrupter (GFCI)

Answer 19

a circuit breaker or receptacle that detects a ground fault by monitoring the imbalance in current flow between the energized and neutral conductors and stops current flow (opens the circuit) when a ground fault is detected.