Generator Glossary

Ammeter - an instrument that measures electric current in amperes.

Amperage (Amps) - the strength of an electrical current measured in amperes.

Armature - the part of an electric motor or generator that consists of wire wound around an iron core and carries an electric current. In motors and generators using direct current, the armature rotates within a magnetic field; in motors and generators using alternating current a magnetic field is rotated about the armature.

Automatic Voltage Regulator (AVR) - a device that regulates (i.e., increases or decreases) the output of a generator by controlling the current and voltage and providing a more linear voltage and frequency. 

Brushless Design - the purpose of the generator brush is to absorb power from the rotating armature of a generator and supply it to the stationary part of the generator. These brushes are known to have a short lifespan. The brushless design extends generator life, calls for lower maintenance, provides a cleaner operation and minimal heat build-up during continuous use.

Circuit Breaker - connects or disconnects the generator output from the output terminals. It also protects the generator from short circuits or overloads.

Dies el Generator – a generator that is powered by diesel fuel. These generators

Exciter Armature - the exciter armature or just the "exciter", generates electricity, which is used for excitation of the field coil. The field coil makes the magnetic field required to generate electricity, which is used for the generators main power output.

Frequency - is the number of complete cycles per second in alternating current direction. The standard unit of frequency is the hertz, abbreviated Hz. If a current completes one cycle per second, then the frequency is 1 Hz; 60 cycles per second equals 60 Hz

Gasoline Generator - a generator that is powered by gasoline. These are the most commonly used generators in the home and at jobsites.

Gro und Fault Interrupters (GFI's) - a safety device that disconnects power from a circuit when a potentially dangerous electrical condition exists. A GFI protects people while fuses or circuit breakers protect equipment.

Heat Rise – when current is put through a conductor, the amps cause resistance and the result is heat; that temperature increase due to resistance is the Heat Rise.

KVA - kilovolt amp which sizes three phase loads.  Can be converted to Kilowatts by multiplying the KVA by the power factor 0.8.

National Electrical Manufacturers Association ( NEMA) – NEMA is the leading trade association in the US representing the interests of electroindustry manufacturers of products used in the generation

Natural Gas Generator – is a generator powered by natural gas.

Ohm - a unit of electrical resistance equal to that of a conductor in which a current of one ampere is produced by a potential of one volt across its terminals.

Phase (Single Phase Power) –  in electrical engineering, single-phase electric power, depending on the country, typically refers to 120V AC or 230V AC. It is carried between two wires: live and a neutral and in many scenarios, a third ground wire for safety. The frequency of single phase is 50 or 60 Hz depending on the country. Typically, single-phase electricity powers most homes.

Phase (Three Phase Power) – with three phase power, voltage is carried through three conductors.  Three-phase power provides a more efficient means of supplying large electrical loads such as, industrial plants and areas, large motors, stadiums and skyscrapers.

Permanent Magnetic Generator (PMG) - PMGs give a lower temperature rise in a generator.

Propane Generator – a generator powered by propane

Rheostat - a continuously variable electrical resistor used to regulate current.

Sizing – generator sizing determines the size of the generator that is needed.

Voltage - the rate at which energy is drawn from a source that produces a flow of electricity in a circuit. Expressed in volts (V)

Voltmeter – an instrument used for measuring the difference in voltage between two points in an electric circuit. Voltmeters typically make use of an ammeter that measures current flow across a known resistance inside the voltmeter; direct-current voltages can then be determined by Ohm's law. Digital voltmeters employ A/D converters to provide the numerical value of the voltage displayed. Generators with this feature allow the operator to quickly tell if the generator is generating the correct voltage, which prevents equipment failure and generator overheating.  

Watt – A unit of power equal to one joule per second; the power dissipated by a current of 1 ampere flowing across a resistance of 1 ohm. An example would be; a generator rated at 6 kW or 6 Kilowatts. If you attempted to use a combination of devices with a total wattage of 10.5 kW, you would most likely cause the generator to overheat, blow a fuse and possibly even the harm the generator.