RV Electrical Systems Level 2 Practice Flashcards

A comprehensive set of vocabulary flashcards covering DC and AC fundamentals, component troubleshooting, and logic control systems based on the RV Technical Institute Level 2 Electrical Systems curriculum.

Ampere ($I$)

The basic unit of measure for electric current, representing the flow when one volt of potential difference is applied across one ohm of resistance.

Aluminum Wire Restriction

Aluminum wire is not allowed in the DC system of an RV because of potential galvanic corrosion; stranded copper must be used instead.

Listed Conductors

Conductors of sizes $6$ through $18$ AWG or SAE used in RV low-voltage systems that must be evaluated by a third-party listing agency such as UL or CSA.

Type I Circuit Breaker

A cycling or self-resetting unit typically used on loads controlled by momentary switches or self-limiting circuits.

Type II Circuit Breaker

An internal-reset breaker that remains open as long as the overload exists and until the power is completely removed.

Type III Circuit Breaker

A manual-reset breaker identifiable by a reset switch or button on its exterior.

Pictorial Wiring Diagram

An actual sketch of unit components showing all physical connections between them.

Ladder Diagram

A diagram used for sequential circuits that indicates processes and parts using symbols, but does not indicate physical location.

Ohm's Law Triangle

A tool used to determine values where $E$ (Voltage) is at the top, and $I$ (Current/Amps) and $R$ (Resistance/Ohms) are at the bottom: $E = I \times R$.

Watt's Law

A mathematical relationship used to determine power where $P$ (Power/Watts) equals $I$ (Current/Amps) multiplied by $E$ (Voltage): $P = I \times E$.

Specific Gravity

A ratio comparing the weight of a substance with the weight of water, used to check the state of charge for a lead-acid battery cell.

Hydrometer

A float-type instrument used to determine the state of charge of a battery by measuring the specific gravity of the electrolyte.

Battery Charging Standard

A fully charged cell results in a specific gravity of $1.265$ at a room temperature of $80^{\circ}\text{F}$ ($27^{\circ}\text{C}$).

Converter

An electrical component used to change $120\,\text{VAC}$ shore power into $12\,\text{VDC}$ for the coach.

Inverter

A solid-state device used to change direct current ($DC$) into alternating current ($AC$).

Photovoltaic Cell

A single solar cell component that has the capacity to produce approximately $0.5\,\text{V}$.

Hot Skin Test

A test using a Non-Contact Proximity Voltage (NCVT) tester or voltmeter to check for electrical shorts on the metallic exterior components of an RV.

GFCI (Ground Fault Circuit Interrupter)

A safety device required on any outlet near a water source or outdoors that trips the circuit if it senses a current imbalance between hot and neutral.

Neutral Isolation

The requirement in RV distribution panels that the neutral circuit remains separate from the ground to prevent reverse polarity from energizing the RV's skin.

Energy Management System (EMS)

A system, also known as a shed system, that automatically removes electrical loads in a preset priority to prevent overloading a generator or shore power.

Can Bus Data

A daisy-chained communication system used in logic control systems to connect multiple RV component controllers.

Omega Board

A multifunction board used by manufacturers like Jayco that includes various latching relays and configurable fuses for logic control.