This page contains an introductory list and definitions for common terms related to industrial diesel engines, generators, electricity, and power generation:
American Public Power Association (APPA): A national service organization that represents 2000 municipal and other state or local publicly owned electric utilities spread across the United States.

Blackout: Sudden disruption of electrical power.

Contactor: It is used in control circuits.

Current: The flow of particles charged by electricity.

Alternating Current (AC): Current flowing from zero to a positive maximum and then back to zero, flows down again to a negative maximum to return back to zero.

Direct Current (DC): Current produced by storage battery or electromagnetic induction, with a unidirectional flow.

Diesel Engine: An internal combustion engine in which fuel oil is burnt by heat produced from air compression. The most commonly bought Industrial Diesel Engines are either Rebuilt Diesel Engine or Used Diesel Engine.

Distribution: Supply of lower voltage electric power from a centralized substation to the point of end use.

Generator: A utility device that converts mechanical energy into electrical energy, available either in the form of direct or alternating current.

Backup Generators: Used for fulfilling emergency load requirement during sudden shortage of power.

Diesel Generator: Starts up and generates power automatically during power cut.

Dynamo: A mechanical device that converts mechanical energy into electrical energy through electromagnetic induction process.

Electric Generator: Generates electricity from a source of mechanical energy.

Engine Generator: Generates electric power with the help of natural gas or diesel reciprocating engine.

Gensets: A handy power generator, converting fuel into electrical power through mechanical ways. Clip-on gensets and Underslung gensets are most popular.

Motor Generator: Normally used either to regulate or condition power from a raw power source like electric utility grid.

Non-Utility Generator: Connected to an electric utility system, Non-utility Generator generates electricity specifically for those not owned by an electric utility.

Standby Generator: Used for power backup in home, Standby Generator is driven by gasoline or LP gas.

Turbine Generator: Running on gas or steam turbine, turbine generator generates electricity through electromagnetic forces caused by steam, water or wind etc.
Generator Parts and Internal Components
Alternator: This device converts mechanical energy into electrical energy.
Battery Charge Rectifier: This component changes AC voltage from the battery charge windings to DC voltage for charging a battery.

Brush: This graphite or copper made conducting element maintains sliding electrical contact between static and moving element.

Core: Core is the magnetic structure built lamination in the generator.

Cradle: Covering a generator or engine, this metal frame provides extra protection from outer disturbances.

Flywheel: Storing energy in a rotating mass form, Flywheel is a very active substitution of chemical batteries.

Ignition Coil: Ignition coil supplies DC voltage to the spark plugs.

Magneto: Built with permanent magnets, Magneto is a special kind of alternator that generates current for ignition in an internal combustion engine.

Rectifier: Rectifier is used for converting alternating current (AC) to direct current (DC).

Relay: Normally used in control circuits, relay is a switch driven by electricity and rules over contactor by virtue of low amperage contacts.

Rotor: Rotor is the element that on, which the rotating of a generator depends.

Stator: Stator is the static or unmovable element of a generator.

Voltage Regulator: By modulating the flow of DC to the rotor, Voltage regulator maintains optimum generator voltage, automatically.

Winding: Winding comprises all the coils of a generator.

Stator winding: Comprises of stator coils with their interconnections.

Rotor winding: Comprises of all the rotor pole windings and connections.
Generator system related terms
Grid: In order to meet the power needs at the grids in different points, a system of power lines and generators, interconnected is used. This is a grid.
Load: Load is that the amount of electric power used by devices associated to electricity generating system.

Off-Peak: A specific period when power demand of a system is comparatively low. Counted from 10 p.m. until 6 a.m., from Monday through Saturday and during the whole day on Sunday by NERC.

Off-Peak Rate: This is the rate of cost for power used during Off-Peak periods.

Peak: Measurement of the maximum load that is consumed within a specified time period.

Phase: Phase measures the uniform periodic change in amplitude or magnitude of an alternating current.

Rated Voltage: The specific voltage measurement at which an engine generator set can start functioning.

Single Point of Failure: Single point of failure is a location in a redundant system where a single powers failure results in loss of electrical power to the critical load.

Standby (Backup) Service: 1. Service through a permanent connection not normally used but available in lieu of, or as a supplement to, the usual source of supply.

Standby Power: This is the backup source of electrical energy that remains dormant and starts functioning as soon as a control device instructs it to.

UPS (Uninterruptible Power Supply): Supplies power automatically and instantly during shortage of power supply. UPS operation is dependent on a primary power source such as the electric utility grid, as it does generate power itself.
Electric Power Units
Amperage: Measurement of the strength or intensity of an electric current in ampere.
Hertz (Hz): unit of frequency that is equal to one cycle per second.

Joule: Measurement of electrical energy equivalent to the work done when a current of one ampere passes through a resistance of one ohm for one second.

Kilowatt (KW): Kilowatt is power needed to do work at the rate of 1000 joules per second.

Kilowatt-hour (KWhr): Total number of kilowatts used per hour. Or 3,600,000 joules.

KVA: KVA is kilovolt-ampere and is the unit of apparent power. KVA is used for measuring the power consumption of non-resistive equipments such as motors, computers, and most non-incandescent lighting.

Volt: Potential difference between two points.

Voltage: Measurement of electrical potential difference expressed in volts.

Watt: Measurement of electrical power. One watt is equal to 1 joule of energy per second.