181:(μF) and voltages from 180 to 330 volts for flash units built into small disposable and compact cameras, increasing for units delivering higher light energy. A typical manufacturer's range includes capacitors operating at 330–380V, with capacitance from 80 to 1,500 μF While normal electrolytic capacitors are often operated at not more than half their nominal voltage due to their high derating, photoflash capacitors are typically operated at their nominal working voltage (labelled as "WV" or "W.V." rather than just "V").
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rate of typically 55 °C, compared to 85 °C–105 °C or more for capacitors for continuous use in electronic equipment. In most electronic applications an electrolytic capacitor can have a capacitance much larger than its nominal value without detracting from circuit performance;
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general-purpose electrolytics are often specified to have capacitance between 20% below and 80% above rated value, although tighter tolerances are available. The light energy of a flash is proportional to the capacitance and large variations are not acceptable, typical tolerance is -10+20%.
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Photoflash capacitors are not subject to the high temperatures of cased electronic equipment in continuous operation, with nearby components and sometimes the capacitors themselves dissipating heat; they are often rated at a maximum
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The light energy emitted by a flash is supplied by the capacitor, and is proportional to the product of the capacitance and the voltage squared; photoflash capacitors may have capacitance in the range 80-240
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Photoflash capacitors are designed to deliver a brief pulse of very high current, and are consequently sometimes used in
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Compared with electrolytic capacitors usually used for power supply filtering at
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The principal properties of a capacitor are capacitance, working voltage,
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power supplies. Their usual purpose is to briefly power a
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Hitachi Photo Flash
Aluminum Electrolytic Capacitors
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