Look for the number on the alternator. If you can't see the entire number, remove the adjustable bracket with a wrench. Take off the alternator and find the part number on it. Once you have the number, you have the identification of your alternator.
Early 20th-century alternator made by in 1909 in, in the power generating hall of the biggest station of the (photograph by, 1911) An alternator is an that converts mechanical energy to electrical energy in the form of. For reasons of cost and simplicity, most alternators use a rotating with a stationary.
Occasionally, a or a rotating armature with a stationary magnetic field is used. In principle, any can be called an alternator, but usually the term refers to small rotating machines driven by automotive and other internal combustion engines. An alternator that uses a for its is called a. Alternators in driven by are called turbo-alternators. Large 50 or 60 Hz alternators in power plants generate most of the world's electric power, which is distributed. In what is considered the first industrial use of alternating current in 1891, workmen pose with a Westinghouse alternator at the.
This machine was used as a generator producing 3000 volt, 133 hertz, single-phase AC, and an identical machine 3 miles away was used as an AC motor. Alternating current generating systems were known in simple forms from the discovery of the in the 1830s.
Rotating generators naturally produced alternating current but, since there was little use for it, it was normally converted into via the addition of a in the generator. The early machines were developed by pioneers such as. Faraday developed the 'rotating rectangle', whose operation was heteropolar – each active conductor passed successively through regions where the magnetic field was in opposite directions.
And also developed early alternators, producing frequencies between 100 and 300. The late 1870s saw the introduction of first large scale electrical systems with central generation stations to power, used to light whole streets, factory yards, or the interior of large warehouses.
Some, such as introduced in 1878, ran better on alternating current, and the development of these early AC generating systems was accompanied by the first use of the word 'alternator'. Supplying the proper amount of voltage from generating stations in these early systems was left up to the engineer's skill in 'riding the load'.
In 1883 the invented the constant voltage generator that could produce a stated output voltage, regardless of the value of the actual load. The introduction of in the mid-1880s led to the widespread use of alternating current and the use of alternators needed to produce it. After 1891, alternators were introduced to supply currents of multiple differing phases. Later alternators were designed for various alternating current frequencies between sixteen and about one hundred hertz, for use with arc lighting, incandescent lighting and electric motors. Specialized radio frequency alternators like the were developed as around World War 1 and used in a few high power stations before vacuum tube transmitters replaced them. Principle of operation.
Main articles: and Another way to classify alternators is by the number of phases of their output voltage. The output can be single phase, or polyphase.
Three-phase alternators are the most common, but polyphase alternators can be two phase, six phase, or more. By rotating part The revolving part of alternators can be the or the magnetic field. The revolving armature type has the armature wound on the rotor, where the winding moves through a stationary magnetic field.
The revolving armature type is not often used. The revolving field type has magnetic field on the rotor to rotate through a stationary armature winding. The advantage is that then the rotor circuit carries much less power than the armature circuit, making the connections smaller and less costly; only two contacts are needed for the direct-current rotor, whereas often a rotor winding has three phases and multiple sections which would each require a slip-ring connection.
The stationary armature can be wound for any convenient medium voltage level, up to tens of thousands of volts; manufacture of slip ring connections for more than a few thousand volts is costly and inconvenient. Cooling methods Many alternators are cooled by ambient air, forced through the enclosure by an attached fan on the same shaft that drives the alternator. In vehicles such as transit buses, a heavy demand on the electrical system may require a large alternator to be oil-cooled. In marine applications water-cooling is also used. Expensive automobiles may use water-cooled alternators to meet high electrical system demands. Specific applications Electric generators.
Alternator mounted on an automobile engine with a pulley (belt not present.) Alternators are used in modern to charge the and to power the electrical system when its is running. Until the 1960s, automobiles used DC generators with.
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With the availability of affordable rectifiers, alternators were used instead. Diesel electric locomotive alternators In later and, the turns an alternator which provides electricity for the (AC or DC). The traction alternator usually incorporates integral silicon diode rectifiers to provide the traction motors with up to 1200 volts DC (DC traction, which is used directly) or the common inverter bus (AC traction, which is first inverted from dc to three-phase ac). The first diesel electric locomotives, and many of those still in service, use DC generators as, before silicon power electronics, it was easier to control the speed of DC traction motors. Most of these had two generators: one to generate the excitation current for a larger main generator. Optionally, the generator also supplies (HEP) or power for. The HEP option requires a constant engine speed, typically 900 RPM for a 480 V 60 Hz HEP application, even when the locomotive is not moving.
Marine alternators Marine alternators used in yachts are similar to automotive alternators, with appropriate adaptations to the salt-water environment. Marine alternators are designed to be so that brush sparking will not ignite explosive gas mixtures in an engine room environment. They may be 12 or 24 volt depending on the type of system installed. Larger marine diesels may have two or more alternators to cope with the heavy electrical demand of a modern yacht. On single alternator circuits, the power may be split between the engine starting battery and the domestic or house battery (or batteries) by use of a or a voltage-sensitive relay. Radio alternators High frequency alternators of the variable-reluctance type were applied commercially to radio transmission in the low-frequency radio bands.
These were used for transmission of and, experimentally, for transmission of voice and music. In the, both the field winding and armature winding are stationary, and current is induced in the armature by virtue of the changing magnetic reluctance of the rotor (which has no windings or current carrying parts). Such machines were made to produce radio frequency current for radio transmissions, although the efficiency was low.
See also.
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