The lead-acid battery is a type of rechargeable battery first invented in 1859 by French physicist Gaston Planté. It is the first type of rechargeable battery ever created. Compared to modern rechargeable batteries, lead-acid batteries have relatively low energy density. Despite this, they are able to supply high surge currents. These features, along with their low cost, make them attractive for use in motor vehicles to provide the high current required by starter motors. Lead-acid batteries suffer from relatively short cycle lifespan and overall lifespan, as well as long charging times.
Cathodic protection is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell. A simple method of protection connects the metal to be protected to a more easily corroded "sacrificial metal" to act as the anode. The sacrificial metal then corrodes instead of the protected metal. For structures such as long pipelines, where passive galvanic cathodic protection is not adequate, an external DC electrical power source is used to provide sufficient current.
A diesel locomotive is a type of railway locomotive in which the power source is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conveyed to the driving wheels. The most common are diesel-electric locomotives and diesel-hydraulic.
Dynamic braking is the use of an electric traction motor as a generator when slowing a vehicle such as an electric or diesel-electric locomotive. It is termed "rheostatic" if the generated electrical power is dissipated as heat in brake grid resistors, and "regenerative" if the power is returned to the supply line. Dynamic braking reduces wear on friction-based braking components, and regeneration lowers net energy consumption. Dynamic braking may also be used on railcars with multiple units, light rail vehicles, electric trams, trolleybuses, and electric and hybrid electric automobiles.
Joule heating is the process by which the passage of an electric current through a conductor produces heat.
A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, or electric multiple unit trains.
Capacitors are manufactured in many styles, forms, dimensions, and from a large variety of materials. They all contain at least two electrical conductors, called plates, separated by an insulating layer (dielectric). Capacitors are widely used as parts of electrical circuits in many common electrical devices.
Electric heating is a process in which electrical energy is converted directly to heat energy. Common applications include space heating, cooking, water heating and industrial processes. An electric heater is an electrical device that converts an electric current into heat. The heating element inside every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor will convert that electrical energy into heat energy. Most modern electric heating devices use nichrome wire as the active element; the heating element, depicted on the right, uses nichrome wire supported by ceramic insulators.
A retarder is a device used to augment or replace some of the functions of primary friction-based braking systems, usually on heavy vehicles. Retarders serve to slow vehicles, or maintain a steady speed while traveling down a hill, and help prevent the vehicle from unintentional or uncontrolled acceleration when travelling on a road surface with an uneven grade. They are not usually capable of bringing vehicles to a standstill, as their effectiveness diminishes as a vehicle's speed lowers. Instead, they are typically used as an additional aid to slow vehicles, with the final braking done by a conventional friction braking system. An additional benefit retarders are capable of providing is an increase in the service life of the friction brake, as it is subsequently used less frequently, particularly at higher speeds. Additionally, air actuated brakes serve a dual role in conserving air pressure.
Storage tanks are containers that hold liquids or compressed gases. The term can be used for reservoirs, and for manufactured containers. The usage of the word "tank" for reservoirs is uncommon in American English but is moderately common in British English. In other countries, the term tends to refer only to artificial containers. In the U.S., storage tanks operate under no pressure, distinguishing them from pressure vessels.
A load bank is a piece of electrical test equipment used to simulate an electrical load, to test an electric power source without connecting it to its normal operating load. During testing, adjustment, calibration, or verification procedures, a load bank is connected to the output of a power source, such as an electric generator, battery, servoamplifier or photovoltaic system, in place of its usual load. The load bank presents the source with electrical characteristics similar to its standard operating load, while dissipating the power output that would normally be consumed by it. The power is usually converted to heat by a heavy duty resistor or bank of resistive heating elements in the device, and the heat removed by a forced air or water cooling system. The device usually also includes instruments for metering, load control, and overload protection. Load banks can either be permanently installed at a facility to be connected to a power source when needed, or portable versions can be used for testing power sources such as standby generators and batteries. They are necessary adjuncts to replicate, prove, and verify the real-life demands on critical power systems. They are also used during operation of intermittent renewable power sources such as wind turbines to shed excess power that the electric power grid cannot absorb.
A brushed DC electric motor is an internally commutated electric motor designed to be run from a direct current power source and utilizing an electric brush for contact.
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices. When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that will flow through an external electric circuit to the positive terminal. When a battery is connected to an external electric load, a redox reaction converts high-energy reactants to lower-energy products, and the free-energy difference is delivered to the external circuit as electrical energy. Historically the term "battery" specifically referred to a device composed of multiple cells; however, the usage has evolved to include devices composed of a single cell.
A liquid resistor is an electrical resistor in which the resistive element is a solution. Fixed-value liquid resistors are typically used where very high power dissipation is required. They are used in the rotor circuits of large slip ring induction motors to control starting current, torque and to limit large electrical fault currents. They typically have electrodes made of welded steel plate, suspended by insulated connections in a conductive chemical solution held in a tank - which may be open or enclosed. The tank body is normally solidly grounded or earthed. A typical unit can be rated for continuous use, or for short periods when used for current limitation in protection systems.
A supercapacitor (SC), also called an ultracapacitor, is a high-capacity capacitor, with a capacitance value much higher than solid-state capacitors but with lower voltage limits. It bridges the gap between electrolytic capacitors and rechargeable batteries. It typically stores 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerates many more charge and discharge cycles than rechargeable batteries.
Teledeltos paper is an electrically conductive paper. It is formed by a coating of carbon on one side of a sheet of paper, giving one black and one white side. Western Union developed Teledeltos paper in the late 1940s for use in spark printer based fax machines and chart recorders.
An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to.
Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another, in the presence of an electrolyte. A similar galvanic reaction is exploited in primary cells to generate a useful electrical voltage to power portable devices. This phenomenon is named after Italian physician Luigi Galvani (1737–1798).
Aluminum electrolytic capacitors are polarized electrolytic capacitors whose anode electrode (+) is made of a pure aluminum foil with an etched surface. The aluminum forms a very thin insulating layer of aluminum oxide by anodization that acts as the dielectric of the capacitor. A non-solid electrolyte covers the rough surface of the oxide layer, serving in principle as the second electrode (cathode) (-) of the capacitor. A second aluminum foil called "cathode foil" contacts the electrolyte and serves as the electrical connection to the negative terminal of the capacitor.
The 1001 class were a class of ten diesel-electric locomotive built by English Electric and Vulcan Foundry in 1955 for Nigerian Railways along with fourteen for the Gold Coast Railways as their 1000 class. Construction and layout was a very similar to the earlier NZR De class.
