Of an output exceeding 750 kVA

85.01 - Electric motors and generators (excluding generating sets). 8501.10 - Motors of an output not exceeding 37.5 W 8501.20 - Universal AC/DC motors of an output exceeding 37.5 W - Other DC motors; DC generators : 8501.31 - - Of an output not exceeding 750 W 8501.32 - - Of an output exceeding 750 W but not exceeding 75 k W 8501.33 - - Of an output exceeding 75 kW but not exceeding 375 kW 8501.34 - - Of an output exceeding 375 kW 8501.40 - Other AC motors, single-phase - Other AC motors, multi-phase : 8501.51 - - Of an output not exceeding 750 W 8501.52 - - Of an output exceeding 750 W but not exceeding 75 kW 8501.53 - - Of an output exceeding 75 kW - AC generators (alternators) : 8501.61 - - Of an output not exceeding 75 kVA 8501.62 - - Of an output exceeding 75 kVA but not exceeding 375 kVA 8501.63 - - Of an output exceeding 375 kVA but not exceeding 750 kVA 8501.64 - - Of an output exceeding 750 kVA (I) ELECTRIC MOTORS Electric motors are machines for transforming electrical energy into mechanical power. This group includes rotary motors and linear motors. (A) Rotary motors produce mechanical power in the form many types and sizes according to whether they operate use or purpose for which they are designed. The motor circumstances in which the motor will operate (e.g., dust motors; non-ri 'd mountings for belt driven motors, or for much vibratios. Many motors may incorporate a fan or other device for keeping the motor cool during running. With the exception of starter motors for internal combustion engines (heading 85.11), the heading covers electric motors of all types from low power motors for use in instruments, clocks, time switches, sewing machines, toys, etc., up to Iarge powerful motors for rolling mills, etc. Motors remain classified here even when they are e uipped with pulleys, with gears or gear boxes, or with a flexible shaft for operating hand too s. The heading includes " outboard motors ",for the pro ulsion of boats, in the form of a unit comprising an electric motor, shaft, propeller and a J d e r . Synchronous motors for clock movements are classified here even if equipped with ears; however such synchronous motors also associated with a clock train are exc uded (heading 91.09). f (B) Linear motors produce mechanical power in the form of a linear motion. Linear induction motors consist essentially of one or more primary members composed of magnetic circuits, generally laminated (stack of magnetic laminahom), on which coils are arranged and of a secondary member, usually in the form of a plate or profile of copper or alum~nium. member is ener ised by These motors generate a propulsive force when the pri applying an alternating current in the presence of the secon ary. The two mem ers are se mated b an airgap, and the translational motion (one member remaining stationary wI ! . ile the o er moves) is produced without mechanical contact. -7 The characteristic features of linear induction motors vary according to the purpose for which they are desi ed : driving hovertrains (the rimary members are carried in the secured to the track); powering vehicles and strad e a rail (secondary (a secondary plate a wheeled trolley travels coils located between the rails); operating overhead conveyors members travel underneath a secondary profile); positioning (secondary pallets are displaced by primary members set into the floor); controlling, e.g., piston purn s and valves (this function may be performed by " polysolenoid " linear motors in whic the shaft (secondary member) moves to and fio inside an annular primary member); positioning on machine-tools; etc. #' g DC linear motors, whose operation uses the interaction of electro-magnets or of electro-magnets and permanent magnets, can be used as alternating or oscillating motors (e.g., for reciprocating pumps, weaving shuttle drives), stepper motors (e.g., small conveyors), etc. This group also includes : (1) Servomotors, presented separately, consisting essentially of an electric motor with speed-reducing gears and equipped with a power transmission device (e.g., lever, ulley) designed to adjust the variable position of a regulating control in a boiler, in a !&mace or in other plant (and possibly provided with an emergency hand-wheel). (2) Self-synchronising units, with a stator carrying three windings angled at 120° and a rotor carrying a single winding connected to two slip rmgs, for use in pairs (synchrotransmitter and synchroreceiver), e.g., in telemetering or remote control systems. (3) Valve actuators, electrical, consisting of an electric motor with reducing gear and drive shaft and, in some cases, with various devices (electric starter, transformer, hand-wheel, etc.) to operate the valve plug. (11) ELECTRIC GENERATORS Machines that produce electrical power from various energy sources (mechanical, solar, etc.) are classified here, provided they are not more specifically covered by any other heading of the Nomenclature. There are two main classes, direct current @C) generators {dynamos), and alternating current (AC) generators (alternators). In general, both consist essentially of a stator mounted in a housing, and a rotating member (the rotor) mounted inside the stator on a shaft driven by the prime mover. In the case of DC generators a commutator with segments is mounted on the rotorshaft. The current produced is collected by a system of carbon brushes which rub the commutator se ents, and is transferred to the external circuit. AC enerators are in most cases brushless and t e current which they roduce is led off directly to e external circuit. In other AC generators the current is collected y slip rings mounted on a rotorshafi and is transferred by a system of carbon brushes which rub the slip rings. f? L t The stator usually consists of a system of electromagnets, but for certain DC enerators (magneto-eIectric generators) a system of permanent mapets is used. The rotor usual y consists of a system of coils of wire mounted on a laminated Iron core; this system is known as the armature. In some AC generators the revolving portion is the field system. f Electric generators may be hand- or pee-operated, but usually they have prime movers (e-g., hydraulic turbines, steam turbines, wlnd engines, reciprocating steam engines, internal combustion piston engines). However, this heading only covers generators when presented without prime movers. The heading also covers photovoltaic generators consisting of panels of photocells combined with other apparatus, e ., storage batteries and electronic controls (voltage regulator, inverter, etc.) and panels or mo ules equip ed with elements, however .sim le (for example, diodes to control the direction of the currentr, which supply the power direct y to, for example, a motor, an electrolyser. f f In these devices, electricity is roduced by means of solar cells which convert solar energy directly into electricity (photovo taic conversion). P The heading covers all electric generators including large generators for power stations; small auxiliary generators used for exciting the windings of other generators; generators of various sizes and types used for supplying current for a variety of urposes e.g., on ships, on farms not connected to an external supply, in chemical industries or electro ysis, and in diesel-electric trains). The heading also excludes : P \ (a) Drums or rollers incorporating an electric motor for belt or roller conveyors (heading 84.31). (b) Vibrator motors and electro-magnetic vibrators of heading 84.79 (see the Explanatory Note to that heading). (c) Electric generators combined with prime movers (heading 85.02). (d) High tension generators (heading 85.04). (e) Primary cells and primary batteries (heading 85.06). ( f ) Generators (d amos am! alterpators) uped in con'unction with internal combustion engines, or for electrical liGg or ~gnallmg e ulpment (headings 85.11 and 85.12, respective y). 02 a kind used for cycles or motor vehicles (g) Solar cells whether or not assembled in modules or made up into panels but not equi ped with elements, however simple, which supply the power directly to, for example, a motor, an e ectrolyser (heading 85.41). P (h) Certain electrical apparatus sometimes known as generators which do not in fact produce electric energy, e.g., signal generators (heading 85.43). (ij) The generators of Chapter 90, for exam le, X-ray generators (heading 90.22); generators designed for demonstrational purposes and unsuita le for other uses (heading 90.23). K PARTS Sub'ect to the general provisions regarding the classification of parts (see the General Note to Section XVT), parts of the machines of this heading are classified in E E G t ~ Y .