摘要 |
Disclosed is a circuit for controlling the load of an asynchronous motor (11), the circuit comprising two capacitors (19, 20), one of which (20) can be connected, by means of a switch (70), in parallel with the other (19). Control is provided by a current sensor (30) and a voltage sensor (40), whose signals (S1, S2) are compared by a comparator (25). Depending on the relative size of the signals (S1, S2) a switch control unit (60) with relaxation hysteresis characteristics switches the switch (70) on or off. The circuit is simple, operates independently of the mains voltage (U) being used and its switch point can be adjusted by means of the current sensor (30).
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