| 摘要 |
PURPOSE:To keep the acuracy of humidity control without replacing a humidity sensor, by correcting the fluctuation of characteristics due to time aging change of the humidity sensor through the changeover of a correction switch at each prescribed time. CONSTITUTION:When an AC voltage from an oscillator 3 is applied to a series circuit consisting of a humidity sensor 1 and a resistor 2, an AC voltage in response to the resistance value of the sensor 1 is produced and this is converted 4 into a DC and applied to a + terminal of a comparator 5. A reference voltage produced at resistors 7, 81-8n is inputted to a - terminal of the comparator 5 and compared with a voltage from the converter 4. When a voltage from the converter 4 is high, a transistor (TR)9 is turned on, a relay 10 is operated and its contact 10a operates an air conditioner 11. When the temperature in the room is decreasd and the output of the converter 4 is reduced, the TR9 is turned off and the unit 11 is stopped. According to the fluctuation of characteristics due to the time aging change of the sensor 1, a changeover switch 6 is switched and the resistors 81-8n are selected to correct the fluctuation of characteristics in the sensor 1. |
