摘要 |
A starting circuit for a single-phase induction motor includes a motor starting positive characteristic thermistor and a triac arranged in a series connection, and a triac control positive characteristic thermistor connected in parallel with the motor starting positive characteristic thermistor, and including one terminal thereof connected to a gate of the triac. The triac control positive characteristic thermistor has a volume in the range of about 4.5 mm<SUP>3 </SUP>to about 30 mm<SUP>3</SUP>. The relationship of (√2xVxsin 45°)/R>=I is maintained with the triac control positive characteristic thermistor within an operating temperature range, where V represents a root-mean-square value of a power source voltage, R represents a resistance of the triac control positive characteristic thermistor, and I represents a gate turn-on current of the triac. The gate turn-on current I at an operating temperature of about 25° C. is about 20 mA or less.
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