Cycloconverter and inverter

Cycloconvertor Cycloconvertor converts AC signal of a particular frequency to another AC signal with different frequency, without using an intermediate DC stage. It is also called single stage frequency converter. it is classified into two. Step up cycloconverter – output frequency is greater than input frequency Step down cycloconverter – output frequency is lesser than …

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Battery, Dual converter and Phase controlled rectifier

Sulphation in a lead acid battery occurs due to incomplete charging. Capacity of a cell is measured in ampere hour. Lead acid battery is used in electric power station. Nickel cadmium battery is used in aeroplanes. Common impurity in battery electrolyte is iron. The indication of the state of charge of a battery is best …

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Chopper, Servomotor and Stepper motor

Chopper Chopper is a high speed on/off semiconductor switch. It is used to control speed of DC series motor and switch mode power supply. Average output voltage of a chopper can be controlled by constant frequency system and variable frequency system. In constant frequency system chopping frequency is fixed and on time of chopper is …

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Air conditioner and refrigerator

Working of Air conditioner / Refrigerator – condenser take high temperature, high pressure vapor from compressor and condensation takes place in the condenser as a result high temperature high pressure liquid come out and it is passed through expansion valve, liquid come out of the valve low temperature low pressure, it is then passed to …

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Various types of electrical measuring instruments

Ammeter and voltmeter Ammeter is always connected in series with circuits, Resistance of ammeter should be low, for that number of turns in operating coil is low. Voltmeter is connected parallel with circuit. Resistance of voltmeter should be high, for that high resistance is placed series with the operating coil. To enhance the measuring capacity …

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