SYNCHROSCOPES The synchroscope is an instrument that shows the relative phase angle and the frequency difference between two alternating voltages. This instrument indicates when alternators are in phase. It also indicates whether the frequency of the incoming generator is higher or lower than that of the generator already connected to the line. There are a […]
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Alternating current fundamentals
AC Instruments and Meters : Synchroscopes, Frequency meters and Recording instruments .
SYNCHROSCOPES The synchroscope is an instrument that shows the relative phase angle and the frequency difference between two alternating voltages. This instrument indicates when alternators are in phase. It also indicates whether the frequency of the incoming generator is higher or lower than that of the generator already connected to the line. There are a […]
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AC Instruments and Meters : Two element wattmeter for three-phase system , Varmeters and Power factor meters.
TWO-ELEMENT WATTMETER FOR THREE-PHASE SYSTEM Unit 10 described power measurement in three-phase circuit systems. Recall that two single-phase wattmeters were used to measure the power in a three-phase, three-wire sys- tem. The two single-phase wattmeters can be combined into a single instrument. The scale of this instrument indicates the sum or difference of the power […]
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AC Instruments and Meters : Two element wattmeter for three-phase system , Varmeters and Power factor meters.
TWO-ELEMENT WATTMETER FOR THREE-PHASE SYSTEM Unit 10 described power measurement in three-phase circuit systems. Recall that two single-phase wattmeters were used to measure the power in a three-phase, three-wire sys- tem. The two single-phase wattmeters can be combined into a single instrument. The scale of this instrument indicates the sum or difference of the power […]
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AC Instruments and Meters : Ammeters and voltmeters , Practical ranges for moving iron instruments and The dynamometer wattmeter.
AMMETERS AND VOLTMETERS Ammeters and voltmeters of the same type operate on the same basic principle. The main difference is that ammeter movements have a few turns of heavy wire and voltmeter movements have many turns of fine wire. Voltmeters also have resistors connected in series with the movement to obtain the desired ranges. PRACTICAL […]
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AC Instruments and Meters : Ammeters and voltmeters , Practical ranges for moving iron instruments and The dynamometer wattmeter.
AMMETERS AND VOLTMETERS Ammeters and voltmeters of the same type operate on the same basic principle. The main difference is that ammeter movements have a few turns of heavy wire and voltmeter movements have many turns of fine wire. Voltmeters also have resistors connected in series with the movement to obtain the desired ranges. PRACTICAL […]
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AC Instruments and Meters : Measurements of AC quantities , Measurement of voltage and current , Rectifier instruments with d’Arsonval movement and Other types of AC voltmeter and ammeter movements.
AC Instruments and Meters MEASUREMENT OF AC QUANTITIES The equipment used to measure ac quantities differs somewhat from the equipment used in dc measurements. This unit will describe the instruments generally used to mea- sure voltage, power factor, VARs, current, watts, frequency, and phase angle. In addition, meters will be described for measuring watt-hours, Watt-hour […]
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AC Instruments and Meters : Measurements of AC quantities , Measurement of voltage and current , Rectifier instruments with d’Arsonval movement and Other types of AC voltmeter and ammeter movements.
AC Instruments and Meters MEASUREMENT OF AC QUANTITIES The equipment used to measure ac quantities differs somewhat from the equipment used in dc measurements. This unit will describe the instruments generally used to mea- sure voltage, power factor, VARs, current, watts, frequency, and phase angle. In addition, meters will be described for measuring watt-hours, Watt-hour […]
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Three-Phase Systems : The three-wattmeter method and Two-phase system
THE THREE-WATTMETER METHOD Many wye-connected systems have a neutral wire in addition to the three line wires. Such a system is called a three-phase, four-wire, wye-connected circuit (Figure 10–18). The neutral wire connects at the common point where the three coil windings terminate in the alternator. The neutral then runs directly to the common point […]
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Three-Phase Systems : The three-wattmeter method and Two-phase system
THE THREE-WATTMETER METHOD Many wye-connected systems have a neutral wire in addition to the three line wires. Such a system is called a three-phase, four-wire, wye-connected circuit (Figure 10–18). The neutral wire connects at the common point where the three coil windings terminate in the alternator. The neutral then runs directly to the common point […]
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