Electrician Terms Glossary
Welcome to the Electrician’s Glossary, your comprehensive resource for understanding the essential terms and concepts in the electrical field. Whether you’re a seasoned professional, an apprentice, or someone passionate about electrical work, this glossary is designed to enhance your knowledge and streamline your work processes. From fundamental units like amperes and volts to specialized components such as circuit breakers and transformers, each entry provides clear and concise explanations tailored to the practical needs of electricians. By familiarizing yourself with these terms, you can improve communication, ensure safety, and boost efficiency on the job. Use this glossary as a handy reference tool to navigate the complex language of electricity and empower your expertise in every electrical project you undertake.
A
Actuator Solenoid: A coil-based device within an actuator housing that converts electrical signals into mechanical movement, often used in fuel injection systems to control components.
Alternating Current (AC): An electric current that periodically reverses direction, commonly used for power distribution in homes and industries.
Alternator: A machine that transforms mechanical energy into electrical energy, typically used in vehicles to charge the battery and power electrical systems.
Ampacity: The maximum current a conductor or device can safely carry without exceeding its temperature rating.
Ampere (Amp): The fundamental unit of electric current, representing the flow of one coulomb of charge per second.
Ampere-Hour (Ah): A measure of electrical charge, indicating the capacity of a battery to provide a certain current over a specific time period (e.g., one ampere for one hour).
Ammeter: An instrument used to measure the current flowing through a circuit, typically connected in series.
Analog Gauge: A display device that uses a moving needle to indicate measurements such as voltage, current, or pressure in real-time.
Analog IC: Integrated circuits designed to process continuous signals, commonly used in audio and sensor applications.
Amplifier: An electronic device that increases the power, voltage, or current of a signal, making it stronger for further processing or transmission.
Amplitude: The maximum value or height of a wave or pulse, indicating the strength or intensity of the signal.
Analog Integrated Circuit: (See "Analog IC")
Armature: The rotating component in electric machines like motors and generators, responsible for converting electrical energy to mechanical energy or vice versa.
Artificial Magnets: Magnets created through manufacturing processes, exhibiting magnetic properties similar to natural magnets.
Atom: The smallest unit of a chemical element, consisting of a nucleus surrounded by electrons, fundamental to electrical conductivity.
Auxiliary Speed Sensor: A secondary sensor that monitors engine speed, providing redundancy and accuracy in engine control systems.
Apparent Power: The product of the current and voltage in an electrical circuit, measured in volt-amperes (VA), representing the total power without considering phase angle.
Arc: A continuous electrical discharge between two conductors, which can generate significant heat and potentially cause fires if uncontrolled.
Arc Fault Circuit Interrupter (AFCI): A safety device that detects unintended electrical arcs and interrupts the circuit to prevent electrical fires.
B
Bendix Drive: A mechanism in starter motors that engages the flywheel to initiate engine cranking, allowing the motor to turn the engine.
Brush: A component that maintains electrical contact with rotating parts like slip rings or commutators, enabling current flow in motors and generators.
Break: (See "Open Circuit")
C
Calibration: The process of adjusting and verifying the accuracy of measuring instruments to ensure they provide correct readings.
Capacitor: An electronic component that stores electrical energy in an electric field, used for filtering, energy storage, and signal processing.
Capacitance: The ability of a component to store an electric charge, measured in farads.
Charge: The process of restoring energy to a battery by applying direct current, reversing the chemical reactions that occur during discharge.
Circuit: A closed loop through which electric current flows, comprising various components like wires, switches, and devices.
Circuit Breaker: A protective device that automatically interrupts electrical flow in a circuit when excessive current is detected, preventing damage or fires.
Conductor: A material that allows electric current to flow easily, such as copper or aluminum wires.
Conduit: A protective tubing or piping used to route and shield electrical wires and cables from physical damage and environmental factors.
Corona: A discharge of electricity from a conductor due to high voltage, leading to ionization of the surrounding air and potential energy loss.
Current: The flow of electric charge through a conductor, measured in amperes, representing the rate of charge movement.
Current Flow: The movement of electrons through a conductor, analogous to water flowing through a pipe.
Cycle: One complete oscillation of an alternating current, encompassing both positive and negative phases.
Cycling: The repeated process of discharging and recharging a battery, essential for maintaining its capacity and longevity.
D
Diagnostic Code: A code generated by a vehicle’s electronic control unit (ECU) that identifies specific faults or issues within the system, aiding in troubleshooting.
Diode: A semiconductor device that allows current to flow in only one direction, commonly used for rectifying alternating current to direct current.
Differentiator Circuit: An electronic circuit that produces an output proportional to the rate of change of the input signal, typically utilizing resistors and capacitors.
Digital IC: Integrated circuits that process discrete signals, representing binary states (0 and 1), used in digital electronics and computing.
Direct Current (DC): An electric current that flows in one constant direction, commonly used in batteries and electronic devices.
Direct Burial: Electrical cables designed to be installed directly underground without additional protection, capable of withstanding soil and moisture exposure.
Discharge: The release of stored electrical energy from a component like a battery or capacitor.
Distributor (Ignition): A device in internal combustion engines that routes high voltage from the ignition coil to the appropriate spark plugs in the correct firing order.
Distributor Lead Connector: The plug connecting wires from the distributor to the vehicle’s electronic control unit, ensuring proper ignition timing and signal transmission.
Dyer Drive: (Assuming a typo for "Bendix Drive"; same description as Bendix Drive)
E
Electrical Field: The region around an electric charge where electric forces are exerted on other charges, influencing their movement.
Electricity: The flow of electrons through a conductor, enabling the operation of electrical devices and systems.
Electrochemical: Pertaining to the chemical processes that produce electrical energy, such as those occurring in batteries and fuel cells.
Electro-Hydraulic Valve: A valve operated by electrical signals to control the flow of hydraulic fluid in a system, combining electrical and hydraulic functionalities.
Electrolyte: A liquid or gel containing ions that facilitates the flow of electric current in batteries and other electrochemical cells.
Electromagnet: A magnet created by passing electric current through a coil of wire surrounding a magnetic core, which can be turned on or off as needed.
Electromagnetic Clutch: A clutch mechanism that uses an electromagnet to engage or disengage power transmission between shafts, allowing for controlled operation.
Electromagnetic Field: The combined electric and magnetic fields generated by moving electric charges, influencing the behavior of other charges and magnetic materials.
Electromagnetic Induction: The process of generating an electric current in a conductor by changing the magnetic field around it, fundamental to the operation of generators and transformers.
Electron: A negatively charged subatomic particle that orbits the nucleus of an atom, responsible for conducting electricity in materials.
Electron Theory: The theory that explains electric current as the flow of free electrons through a conductor, forming the basis for understanding electrical conduction.
Electronics: The branch of science and technology concerned with the behavior and control of electrons in devices and circuits.
Electronic Control Unit (ECU): A computerized system in vehicles that manages engine functions, diagnostics, and other electronic systems based on sensor inputs.
Electronic Governor: A component within the engine controller that regulates fuel delivery and engine speed based on various inputs like throttle position and temperature.
Electronic Ignition System: An ignition system that uses electronic components to control the timing and delivery of spark to engine cylinders, replacing traditional mechanical systems.
Element:
A fundamental substance that cannot be broken down by chemical means.
In batteries, the assembly of negative and positive plates separated by a separator within a cell compartment.
Engine Controller: The electronic module that oversees engine operations, including fuel injection, diagnostics, and communication with other vehicle systems.
F
Field Effect Transistor (FET): A type of transistor that controls current flow using an electric field, featuring terminals called source, drain, and gate.
Fixed Resistor: A resistor with a constant resistance value, used to control current and voltage in electrical circuits.
Frequency: The number of cycles per second in an alternating current, measured in Hertz (Hz), indicating how rapidly the current changes direction.
Fundamental Law of Magnetism: The principle that opposite magnetic poles attract each other, while like poles repel, governing the behavior of magnetic fields.
Fuse: A protective device consisting of a metal wire that melts when excessive current flows through it, thereby interrupting the circuit to prevent damage or fires.
G
Gate: A component in digital logic circuits that performs logical operations based on input signals, producing binary outputs (0 or 1).
Generator: A machine that converts mechanical energy into electrical energy, supplying power to electrical systems and devices.
Grid: The network of wires forming the structural framework of a battery, to which the active materials are attached for conducting electricity.
Ground: A reference point in an electrical circuit from which voltages are measured and a common return path for electric current, enhancing safety by preventing unwanted voltage build-up.
Grounded Circuit: A circuit connected to the ground to provide a safe path for excess current, preventing electrical hazards and ensuring system stability.
Growler: A testing device used to check the functionality and performance of a generator or motor's armature by simulating load conditions.
Ground Fault: An unintended electrical path between a power source and the ground, which can cause electric shocks or fires if not properly protected against.
Grounded Conductor: A conductor intentionally connected to the ground, providing a reference potential and a safety pathway for electrical current.
H
Hydrometer: An instrument used to measure the specific gravity of liquids, such as the electrolyte concentration in batteries.
Henry: The unit of inductance in the International System of Units (SI), representing the inductance that induces one volt when the current changes at one ampere per second.
Hertz: The unit of frequency, equal to one cycle per second, used to quantify the rate of oscillations in alternating current.
I
Ignition Control Unit: The module that houses transistors and resistors to manage the timing and operation of the ignition system, ensuring proper spark delivery to engine cylinders.
Impedance: The total opposition a circuit presents to alternating current, encompassing both resistance and reactance, measured in ohms.
Inductance: The property of a conductor by which a change in current induces a voltage in itself and nearby conductors, measured in henries.
Inductor: A passive electrical component consisting of a coil of wire that creates a magnetic field when current flows through it, used for energy storage and filtering.
Insulator: A material that resists the flow of electric current, used to protect and separate conductive parts in electrical systems.
Insulated Gate Field Effect Transistor (IGFET): A transistor with an insulated gate, offering high input impedance and efficient control of current flow in electronic circuits.
Integrated Circuit (IC): A miniaturized electronic circuit containing multiple interconnected components like transistors, resistors, and capacitors on a single chip.
Integrator Circuit: An electronic circuit that produces an output proportional to the integral of its input signal, commonly used in signal processing and control systems.
Inverter: A device that converts direct current (DC) into alternating current (AC), enabling the use of AC-powered devices with DC sources like batteries.
Ion: An atom or molecule with an electric charge due to the loss or gain of electrons, essential for conducting electricity in electrolytes and plasmas.
Isolation Diode: A diode placed in a circuit to prevent current from flowing back into a power source, ensuring proper directionality of current flow and protecting components.
L
Light Emitting Diode (LED): A semiconductor device that emits light when an electric current passes through it, used for efficient and long-lasting lighting and displays.
Lines of Force: Imaginary lines used to represent the direction and strength of electric or magnetic fields around charges and magnets.
Liquid Crystal Display (LCD): A flat-panel display technology that uses liquid crystals to modulate light, commonly found in screens and monitors.
M
Magnet: An object that produces a magnetic field, capable of attracting ferromagnetic materials like iron and influencing other magnets.
Magnetic Field: The area around a magnet where magnetic forces are exerted, affecting the movement of charged particles and other magnets within the field.
Magnetic Flux: The measure of the total magnetic field passing through a given area, indicating the strength and extent of the magnetic field.
Magnetic Induction: The process of generating a magnetic field in a material by exposing it to an external magnetic field, fundamental to transformer and motor operation.
Magnetic Lines of Force: Imaginary lines that depict the direction and strength of a magnetic field, showing how magnetic forces interact around a magnet.
Magnetic Material: Materials that can be magnetized, such as iron, nickel, and cobalt, which respond to magnetic fields and retain magnetism.
Magnetic North: The direction that the north end of a compass needle points, aligned with Earth's magnetic north pole, used for navigation.
Magnetic Pickup Assembly: A component in ignition systems containing magnets and coils that detect engine speed and position, aiding in spark timing control.
Magnetic South: The opposite end of a magnet to the magnetic north, where magnetic field lines converge, influencing nearby magnetic materials.
Magnetic Switch: A switch operated by a magnetic field, often used in security systems and automated controls to open or close electrical circuits.
Magnetism: The physical phenomenon produced by the motion of electric charges, resulting in attractive or repulsive forces between materials.
Microprocessor: A compact integrated circuit designed to perform computational tasks in electronic devices, serving as the brain of many systems.
Milliampere: One-thousandth of an ampere, a unit of electric current used for measuring small currents in circuits.
Molecule: A group of atoms bonded together, representing the smallest unit of a chemical compound that retains its chemical properties.
Motor: A device that converts electrical energy into mechanical energy, used to drive machinery, vehicles, and other equipment.
Multimeter: A versatile instrument that can measure multiple electrical properties, including voltage, current, and resistance, essential for troubleshooting.
Mutual Induction: The phenomenon where a change in current in one coil induces a voltage in a nearby coil through the magnetic field, used in transformers and inductive sensors.
N
Natural Magnet: A magnet found in nature, such as lodestone, that exhibits persistent magnetic properties without artificial processing.
Negative: The electrical charge carried by electrons, indicating a surplus of electrons in an atom or object.
Neutron: An uncharged subatomic particle found in the nucleus of an atom, contributing to its mass and stability.
Non-Magnetic Material: Materials that do not exhibit magnetism and are not attracted to magnets, such as plastic, glass, or wood.
Normally Open: A switch configuration where the contacts remain open (disconnected) when no external action is applied, requiring activation to close.
Normally Closed: A switch configuration where the contacts remain closed (connected) when no external action is applied, requiring activation to open.
O
Ohm: The unit of electrical resistance, representing the resistance between two points when one volt of potential difference causes one ampere of current to flow.
Ohmmeter: An instrument used to measure electrical resistance in a circuit, typically part of a multimeter.
Ohm's Law: A fundamental principle stating that current equals voltage divided by resistance (I = V/R), describing the relationship between these electrical quantities.
Open Circuit: A circuit in which the path for current flow is interrupted, preventing electrical current from flowing.
Operational Amplifier: An integrated circuit used to amplify voltage signals in various electronic applications, offering high gain and versatility.
Overload: A condition where excessive current flows through a circuit, potentially causing overheating and damage to components.
Open or Open Circuit: An interruption in a circuit that stops current flow, similar to a closed valve stopping water flow.
P
Parallel Circuit: An electrical circuit arrangement where components are connected alongside each other, providing multiple paths for current to flow.
Permanent Magnet: A magnet that retains its magnetic properties indefinitely without external power, used in various applications like motors and sensors.
Piezo Electric Device: A device that generates an electric charge in response to mechanical stress, commonly used in sensors and actuators.
Plate: In batteries, the conductive surfaces where chemical reactions occur to store and release electrical energy.
Polarity: The orientation of the positive and negative terminals in an electrical device, determining the direction of current flow.
Pole: The distinct ends of a magnet where its magnetic force is concentrated, such as north and south poles.
Pole Shoes: Components in motors and generators that guide magnetic fields and support the windings around the poles.
Positive: The electrical charge carried by protons, indicating a deficiency of electrons in an atom or object.
Potentiometer: A variable resistor used to adjust voltage levels in circuits, often serving as a control knob in devices.
Power: The rate at which electrical energy is consumed or generated, measured in watts.
Power Factor: The ratio of real power used to perform work to apparent power in an AC circuit, indicating efficiency.
Power Switch Transistor: A transistor used to control the flow of large currents in response to smaller input signals, acting as a switch.
Primary Speed Sensor: The main sensor that monitors engine speed, providing data to the engine controller for operation adjustments.
Principle of Turning Force: The concept that magnetic forces acting on current-carrying conductors create mechanical movement, as seen in electric motors.
Printed Circuit Board: A board with etched pathways that connect electronic components, forming the backbone of electronic devices.
Proton: A positively charged subatomic particle found in the nucleus of an atom, determining the element’s identity.
Pulse: A temporary change in voltage or current, often used in digital signaling and control systems.
Pulse-Width-Modulated (PWM): A technique for controlling power delivery by varying the width of voltage pulses, commonly used in motor control and power regulation.
R
Rectifier: A device that converts alternating current (AC) to direct current (DC), typically using diodes.
Regulator: A component that maintains a constant voltage or current level in an electrical circuit, ensuring stable operation.
Relay: An electrically operated switch that uses a low-power signal to control a higher-power circuit, providing isolation and control.
Reluctance: The opposition to the formation of a magnetic field in a magnetic circuit, similar to electrical resistance in an electric circuit.
Reluctor: A component in ignition systems that interacts with sensors to provide signals based on rotational position, aiding in timing control.
Resistance: The opposition to electric current flow within a material, measured in ohms, affecting how much current flows for a given voltage.
Resistor: An electronic component that limits or regulates the flow of electrical current in a circuit, having a specific resistance value.
Rheostat: A variable resistor used to adjust current levels in a circuit, allowing for fine control of electrical parameters.
Right-Hand Rule: A mnemonic used to determine the direction of magnetic fields relative to current flow, essential in electromagnetism and motor design.
Rotor: The rotating part of an electric machine, such as a motor or generator, where electromagnetic induction occurs to produce motion or electricity.
S
Self-Induction: The phenomenon where a changing current in a coil induces a voltage in the same coil, opposing the change in current.
Semiconductor: A material with electrical conductivity between that of a conductor and an insulator, fundamental to electronic components like diodes and transistors.
Sending Unit: A component that transmits data or signals from a remote location to a display or control unit, often used in instrumentation.
Separator: A material used in batteries to keep positive and negative plates apart, preventing short circuits while allowing ion flow.
Sensor: A device that detects and responds to physical or electrical stimuli, providing data for control systems.
Series Circuit: An electrical circuit where components are connected end-to-end, providing a single path for current flow.
Series-Parallel Circuit: A hybrid circuit arrangement combining elements of both series and parallel connections, allowing multiple paths and consistent current.
Short Circuit: An unintended connection between two points in a circuit, allowing current to bypass intended paths, often causing excessive current and potential damage.
Shunt: A low-resistance path added to a circuit to allow current to bypass certain components or to enable current measurement.
Slip Ring: A continuous electrical connection that allows current to flow between a rotating and a stationary part, used in generators and motors.
Solenoid: A coil of wire that generates a magnetic field when current flows through it, often used to actuate mechanical devices.
Solid-State Circuit: An electronic circuit that uses semiconductor devices like transistors and diodes, with no moving parts.
Spark Plugs: Devices in internal combustion engines that create a spark to ignite the fuel-air mixture, essential for engine operation.
Specific Gravity: The ratio of the density of a substance to the density of a reference substance, commonly used to assess battery electrolyte concentration.
Sprag Clutch Drive: A type of mechanical clutch used in starter motors to engage the flywheel without slipping.
Starter Motor: A motor that turns the engine to initiate the combustion process, using electrical energy from the battery to produce mechanical motion.
Stator: The stationary part of an electric machine, containing windings or permanent magnets to create a magnetic field interacting with the rotor.
Storage Battery: A battery designed to store electrical energy chemically and release it as needed, consisting of multiple electrochemical cells.
Sulfation: The buildup of lead sulfate crystals on battery plates, reducing battery performance and capacity over time.
Switch: A device that opens or closes electrical circuits, controlling the flow of current to turn devices on or off.
Synchrograph: A device used to test and analyze the synchronization of generators or motors, ensuring proper phase alignment.
T
Tachometer: An instrument that measures the rotational speed of a shaft or motor, usually displayed in revolutions per minute (RPM).
Temporary Magnet: A magnet that exhibits magnetic properties only when an external magnetic field is applied, losing magnetism when the field is removed.
Thermistor: A resistor whose resistance varies significantly with temperature, used for temperature sensing and control in circuits.
Transformer: A device that transfers electrical energy between circuits through electromagnetic induction, used to increase or decrease voltage levels.
Transient Voltage Protection Module (TVP): A device that safeguards electronic components by diverting or blocking sudden voltage spikes, preventing damage.
Transistor: A semiconductor device used to amplify or switch electronic signals and electrical power, fundamental to modern electronics.
Trimmer Resistor: A variable resistor designed for fine-tuning circuit parameters during calibration or adjustment.
V
Vacuum Fluorescent Display (VFD): A display technology that uses vacuum tubes and phosphors to emit bright, clear images, commonly seen in appliances and instruments.
Variable Resistor: A resistor with an adjustable resistance value, allowing for control over current or voltage in a circuit.
Viscosity: A measure of a fluid's resistance to flow, relevant in applications involving lubrication and hydraulic systems.
Volt: The unit of electrical potential difference or electromotive force, indicating the energy per unit charge driving current through a circuit.
Voltage: The electrical force that pushes current through a conductor, measured in volts and representing the potential energy difference between two points.
Voltage Regulator: A device that maintains a constant voltage level in a circuit, ensuring stable operation of electrical components.
Voltmeter: An instrument used to measure the electrical potential difference between two points in a circuit, typically connected in parallel.
Volt-Ampere (VA): A unit of apparent power in an electrical circuit, representing the product of voltage and current without considering phase angle.
W
Watt: The unit of power in the International System of Units (SI), equal to one joule per second, indicating the rate of energy transfer.
Watt-hour (Wh): A unit of energy representing the amount of power consumed or generated over one hour, commonly used to measure electrical energy usage.
Wave: A disturbance that travels through space and matter, transferring energy without transporting matter, as seen in electrical signals.
Waveform: A graphical representation of the shape of a signal's voltage or current over time, illustrating characteristics like amplitude and frequency.
Winding: The coils of wire wrapped around a core in transformers, motors, and inductors, essential for creating magnetic fields and inducing voltages.
Wiring Harness: An assembly of wires and connectors bundled together to transmit electrical power and signals throughout a system, commonly used in vehicles and machinery.
Z
Zener Diode (Reverse Bias Direction Diode): A type of diode designed to operate in reverse bias, allowing current to flow when a specific breakdown voltage is reached, used for voltage regulation.