| 摘要 |
PURPOSE:To prevent the danger which may happen at the start of operation by a system wherein relay circuit is put together so that the output signal of a temperature setter becomes below the definite value when the device is brought to a standstill. CONSTITUTION:A relay 30 and a parallel circuit comprising a snap switch 31 and a normally open contact 32 are connected in series. The temperature setter 22 consisting of a series circuit comprising fixed resistors R1-R3 is connected in parallel with a normally closed contact 33. A main operating unit 20 consists of the relay 30 connected in series with the above-mentioned parallel circuit and the normally closed contact 33 installed between an operating switch 24 and the temperature setter 22. A relay 30, a snap switch 31 and normally open contact 32 is arranged between a priority switch 28 and a temperature setter 23 in subsidiary operating unit 21. A normally closed contact 33, which is to short fixed resistors R2 and R3 for setting high temperature, is provided in the temperature setter 23. Accordingly, when the operating switch is turned on, without reference to the change-over position of a change-over switch 29 in the temperature setter 22, the hot water supply under the condition, that the change-over switch 29 in the temperature setter 22 is connected to a contact A, is performed or the hot water with the lowermost temperature is supplied outside, resulting in preventing the danger of boiling water supply. |
