ARMATURE VOLTAGE LOSSES (NEGLECTING ARMATURE REACTION) All alternator armatures have coils and generate ac voltages. Thus, the equivalent diagrams of such alternators must show a resistor and an inductor (Figure 12–18A). The equivalent diagram in this case is a series RL circuit. This means that a series circuit analysis can be made to solve for […]
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Alternating current fundamentals
Alternating-Current Generators : Armature voltage losses (neglecting armature reaction).
ARMATURE VOLTAGE LOSSES (NEGLECTING ARMATURE REACTION) All alternator armatures have coils and generate ac voltages. Thus, the equivalent diagrams of such alternators must show a resistor and an inductor (Figure 12–18A). The equivalent diagram in this case is a series RL circuit. This means that a series circuit analysis can be made to solve for […]
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Alternating-Current Generators : The stator windings , Ventilation and Operation of a rotating field .
THE STATOR WINDINGS It was stated earlier that the dc armature generates alternating current. If properly connected slip rings are used, instead of a commutator, both alternating voltage and current can be obtained. For a revolving armature type of single-phase alternator having a small capacity and low voltage, the armature winding generally used is the […]
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Alternating-Current Generators : The stator windings , Ventilation and Operation of a rotating field .
THE STATOR WINDINGS It was stated earlier that the dc armature generates alternating current. If properly connected slip rings are used, instead of a commutator, both alternating voltage and current can be obtained. For a revolving armature type of single-phase alternator having a small capacity and low voltage, the armature winding generally used is the […]
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Alternating-Current Generators : Introduction Revolving armature-type alternator and Revolving field-type alternator.
Alternating-Current Generators INTRODUCTION It was shown in Unit 1 that an alternating voltage having a sine-wave pattern is induced in a single conductor, or armature coil, rotating in a uniform magnetic field with station- ary field poles. Similarly, an emf is generated in stationary armature conductors when the field poles rotate past the conductors. A […]
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Alternating-Current Generators : Introduction Revolving armature-type alternator and Revolving field-type alternator.
Alternating-Current Generators INTRODUCTION It was shown in Unit 1 that an alternating voltage having a sine-wave pattern is induced in a single conductor, or armature coil, rotating in a uniform magnetic field with station- ary field poles. Similarly, an emf is generated in stationary armature conductors when the field poles rotate past the conductors. A […]
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AC Instruments and Meters : Clamp-on ammeters and The oscilloscope.
CLAMP-ON AMMETERS Another meter frequently used is the clamp-on ammeter (Figure 11–38). Most of these meters operate on the current transformer principle. The movable jaw is the core of a cur- rent transformer. The range selection switch connects the meter to different taps on the transformer (Figure 11–39). The conductor around which the movable jaw […]
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AC Instruments and Meters : Clamp-on ammeters and The oscilloscope.
CLAMP-ON AMMETERS Another meter frequently used is the clamp-on ammeter (Figure 11–38). Most of these meters operate on the current transformer principle. The movable jaw is the core of a cur- rent transformer. The range selection switch connects the meter to different taps on the transformer (Figure 11–39). The conductor around which the movable jaw […]
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AC Instruments and Meters : Thermal converters , The watt-hour meter and Digital multimeters .
THERMAL CONVERTERS Thermal converters change ac voltage and current signals into a dc signal in millivolts. This signal is proportional to the product of VI cos 8. AC watts can be measured using a thermal converter with a dc recording or indicating device. Figure 11–32 is a schematic diagram of a single-phase thermal converter. The […]
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AC Instruments and Meters : Thermal converters , The watt-hour meter and Digital multimeters .
THERMAL CONVERTERS Thermal converters change ac voltage and current signals into a dc signal in millivolts. This signal is proportional to the product of VI cos 8. AC watts can be measured using a thermal converter with a dc recording or indicating device. Figure 11–32 is a schematic diagram of a single-phase thermal converter. The […]
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