chapter 24 Flashcards
What do electrical prints include?
Electrical prints include pictorial drawing, electrical layouts, schematic diagrams, and line diagrams.
A drawing that shows the length, height, and depth of an object in one view. These drawings indicate details such as holes and shoulders of an object as seen by the eye.
Pictorial drawings
A drawing that indicates the connections of all devices and components in a residential electrical system.
electrical layout
An electrical layout typically indicates the devices and components of a system with _______.
rectangles or circles
An assembly of conductors (wires), electrical devices (switches and receptacles), and components (lights and motors) through which current flows.
electrical circuit
What stops current from following in a circuit?
a broken wire, a loose connection, or a switch in the OFF position stops current from flowing in a circuit.
What are the five basic parts of a residential and electrical circuit?
- A component (load) that converts electrical energy into some other usable form of energy such as light heat, motion.
- a source of electricity.
- Conductors to connect the individual devices and components.
- a method of controlling the flow of electricity (switch)5. Protection devices (fuses or circuit breakers) to ensure that the circuit operates safely within electrical limits.
All residential circuits use the ___ as the power source for the dwelling.
service panel
the wires pulled through conduit or metallic and nonmetallic cables.
Conductors
What are some examples of control devices?
Single pole switches, three-way switches, motion detectors, timers, or thermostats.
What are typical loads found in a residence?
lamps, motors, televisions, radios, and appliances
What is the typical overcurrent device used to protect a residential electrical circuit?
Circuit breaker
Flipping a single-pole switch to the ON position allows current to pass from the ________, through the closed contacts of the wall switch, through the lamp, and on through the _________, forming a complete (path) or ____.
hot conductor
common conductor
circuit
What is used to control a sump pump?
A float or pressure switch
Current must flow from the power source, through the load, and ___________, making a complete circuit.
back to the power source
These automatically detect the absence of light and respond by sending commands to loads (lights). A ____ responds to the absence of light by turning lights inside and outside a dwelling on and off.
Photo cell
How is a photocell controller mounted?
to standard octagon electrical boxes or directly to controlled lighting.
is a drawing and list that indicates the devices to be used, the location of the electrical devices, and wiring methods.
electrical plan
Electrical plans indicate the use of switches, lights, and receptacle with ______.
Symbols
Understanding _____ is the key to understanding electrical plans.
electrical device symbols
What does a good electrical plan include?
the location of all major electrical devices and connections
These are also used to determine the number of openings in walls and ceilings and to estimate the amount of wire and conduit that is required for the job.
Electrical plans
A complete electrical plan or set of plans is developed into two main parts:
Component plans and wiring plans
Is a group of schedules that state the required locations for receptacles, lights, and switches according to the NEC and local codes.
Component plan
Is a list of electrical equipment indicating manufacturer, specifications, and the number of room or area.
component list
A partial component list is a _____.
component schedule
a drawing that indicates the placement of all electrical devices and components and the wiring required to connect all the equipment into circuits.
Wiring plan
What is the purpose of a wiring plan?
The purpose of a wiring plan is to group individual electrical devices into specific circuits.
Are the basis for all electrical work performed at a residence.
electrical plan
A wiring plan is essential when determining the number of components per circuit (load) and the best route for ___.
wire
Time spent studying a wiring plan aids in anticipating problems and reducing__________.
The amount of materials required.
What do slash marks indicate?
Slash marks indicate the number of conducting wires in cables or conduit.
What does an arrow symbolize?
The circuit connection to the service panel
Indicate the size of wire that must be used and the amount of overload protection that must be provided. The specifications set by manufacturers must agree with or surpass the standards of NEC.
Manufacturer specs