10. Sequence timing chart
11. Description of circuit operation
(1) Precautions for turning ON/OFF the power switch
1When the power switch is turned ON, the power indicator lamp (LED1) and lighting lamps (LED3 to LED6) are lit after one second, and the hand dryer can then be operated.
•If the power switch is turned OFF (or if power failure occurs) while the blower motor is rotating, in order to protect the circuitry, the hand dryer will not operate for five seconds the next time the power switch is turned ON (or power failure is recovered) when the hands are inserted.
•The hand dryer does not operate when the hands are inserted while the power indicator lamp and lighting indicator lamps are unlit. The microcomputer (IC1) performs initial settings such as determining the power supply frequency and setting the hand detection sensor's sensitivity.
2When the power switch is turned OFF, the power indicator lamp and lighting lamps are unlit, and the operation of the hand dryer is disabled.
•It requires approximately 60 seconds for the voltage in the circuitry to discharge. Therefore, wait at least 60 seconds before plugging/unplugging the connector or replacing the circuitry.
•If an abnormality occurs, the hand dryer continues to show error display until electric power in the circuitry finishes discharging (i.e., until the microcomputer resets) even after the power switch is turned OFF.
3In regions where the power supply voltage is either 220 VAC or 230 VAC, the air volume and power consumption in the initial operation after the power switch is turned ON may be lower than those in the second and succeeding operations, although it is within the normal ranges.
•The hand dryer detects the power supply voltage and sets the blower motor output so that the rated air volume and power consumption are used with each power supply voltage of 220 VAC, 230 VAC or 240 VAC.
•The hand dryer determines the power supply voltage and sets the blower motor output in the following cases:
-When 15 seconds have elapsed after the power switch is turned ON
-When the blower motor has stopped in the event the hand dryer was operated within 15 seconds
•Immediately after the power switch is turned ON, the hand dryer cannot detect an accurate power supply voltage because of the effect of the rush current. Therefore, the blower motor output is temporarily set at 240 VAC.
•When the hand dryer is operated within 15 seconds of turning ON the power switch, it is operated at either 220 VAC or 230 VAC with a setting of 240 VAC in regions where the power supply voltage is either 220 VAC or 230 VAC. Therefore, the air volume and power consumption will slightly decrease.
—21—