CIRCUITS
An electrical circuit in which current can flow to and from the power source along more than one path.
WHAT IS A PARALLEL CIRCUIT?
is the voltage measured between any two conductors in a three‑phase system
WHAT IS LINE VOLTAGE?
states that electrical power (P, in watts) equals voltage (V, in volts) multiplied by current (I, in amps): P = V × I. This relationship defines how much energy a circuit uses or delivers and is fundamental in electrical design and troubleshooting.
WHAT IS WATTS LAW?
a German physicist and mathematician best known for formulating Ohm's law
WHO IS GEORG OHM?
Each individual path that makes up a circuit.
WHAT IS A BRANCH?
An electrical circuit that includes a combination of series and parallel circuits.
WHAT IS A SERIES-PARALLEL CIRCIUT?
COMBINATION OR COMPLEX
DBL PTS
how strongly a material resists the movement of electric charges.
WHAT IS RESISTANCE?
THEY certify that equipment/component standards are met.
WHO IS THE UL?
UNDERWRITERS LABORTORIES
Scottish inventor and engineer whose improvements to the steam engine were pivotal to the Industrial Revolution.
WHO IS JAMES WATTS?
the unit of measure for current
WHAT IS AMPERE?
a closed loop that allows electricity to flow from a power source, through a device, and back again.
WHAT IS A SIMPLE CIRCUIT?
the rate at which electric charge flows through a conductor or space, measured in amperes (A), and is defined as the net movement of charged particles such as electrons or ions
WHAT IS A CURRENT?
DBL PTS
the maximum electric field an insulating material can withstand without breaking down and becoming electrically conductive
WHAT IS DIELECTRIC STRENGTH?
invented the first modern air‑conditioning system in 1902 and later founded the Carrier Corporation in 1915, establishing the HVAC industry.
WHO IS WILLIS CARRIER?
WHAT ARE OHM'S?
an electric path where parts are connected in one single line
WHAT IS A SERIES CIRCUIT?
An electric current that periodically reverses direction and changes its magnitude continuously with time, unlike direct current (DC), which flows in a single direction
WHAT IS ALTERNATING CURRENT?
a safety device that monitors electrical current and instantly shuts off power when it detects a ground fault, helping prevent shock or electrocution.
WHAT IS A GFCI?
patented one of the earliest modern gas‑powered central heating furnace designs in 1919, laying the foundation for today’s forced‑air heating systems.
WHO IS ALICE H PARKER?
TRIPLE PTS
An electrical device that reduces the voltage from a higher level (primary side) to a lower level (secondary side) while proportionally increasing the current, in accordance with the law of conservation of energy
WHAT IS A STEP-DOWN TRANSFORMER?
the intentional connection of non-current-carrying metal parts—like equipment frames, enclosures, and pipes—to create a low-resistance path
WHAT IS BONDING?
TRIPLE PTS
an electric current flowing in one direction only
WHAT IS A DIRECT CURRENT?
A material that has an atomic structure that does not readily release electrons, thus restricts the flow of electrons through it.
WHAT IS AN INSULATOR?
was an Italian chemist and physicist renowned for pioneering work in electricity, including inventing the electric battery
WHO IS ALESANDRO VOLTA?
an electrical device that increases voltage from its primary to secondary winding while proportionally decreasing current, enabling efficient power transmission and voltage boosting for various applications.
WHAT IS A STEP-UP TRANSFORMER?
TRIPLE PTS
the conductor that provides the normal return path for current from the load back to the power source, completing the circuit and enabling devices to operate
WHAT IS NEUTRAL?
In a zoned system, this is the thermostat that governs system operation and receives temperature input and calls for operation from slave thermostats.
What is a master thermostat?
The force behind the movement of electrons. Also known as electromotive force (EMF)
WHAT IS ALSO KNOWN AS VOLTAGE?
TRIPLE PTS
as an American inventor, businessman, and innovator who held a record 1,093 patents and pioneered technologies such as the phonograph, incandescent light bulb, and modern electric power systems
WHO IS THOMAS EDISON?
In basic terms, a sensing device that reacts to temperature change. More broadly, a temperature control that starts and stops an HVAC system when preset temperature conditions are reached
What is a thermostat?
procedure is an essential electrical safety check. Performed after locking out and tagging out (LOTO) a system, it ensures a circuit is completely de-energized and proves your voltage meter is working correctly before and after the test
WHAT IS THE LIVE-DEAD-LIVE METHOD?
WHAT IS A WIFI-ENABLED TSTAT?
TRIPLE PTS
The electric charges interact: like charges repel, opposite charges attract, and the force between them follows Coulomb’s Law, which depends on the charges’ magnitudes and the distance between them
WHAT ARE THE LAWS OF CHARGES?
DBL PTS
The National Electrical Manufacturers Association, the largest U.S. trade association for electrical equipment manufacturers, setting industry standards and advocating for safety, efficiency, and innovation.
WHO IS NEMA?
diagram represents the functional relationships between components using simplified, symbolic graphics. It focuses on how a system works rather than how it looks.
WHAT IS A SCHEMATIC?
a safety connection between an electrical system and the earth itself.
WHAT IS GROUND?
an OSHA‑required safety procedure (29 CFR 1910.147) that isolates machinery from hazardous energy using locks and warning tags to prevent accidental startup during maintenance.
WHAT IS LOTO?
The push or pull between electrically charged particles, governed by Coulomb’s law, where like charges repel and opposite charges attract
WHAT IS ELECTRICAL FORCE?
The Occupational Safety and Health Administration, a U.S. federal agency responsible for ensuring safe and healthy working conditions for employees.
WHO IS OSHA?
An electrically operated high‑power switch used to control heavy loads such as motors, heaters, lighting, and industrial machinery. It uses an electromagnetic coil to open or close its contacts, allowing a low‑power control circuit to safely switch a high‑power circuit.
WHAT IS A CONTACTOR?