| 摘要 |
<p>PURPOSE:To heat water to a desired temperature within a prescribed time zone even when a fault of a central processing unit and a circuit fault take place, by a system wherein a self-control instruction generating means gives a self-control instruction necessary for electrifying a heater to an electrification control device on the basis of the result of computation of a necessary electrification time computing means. CONSTITUTION:In the case when a control instruction is not transmitted by a limit time due to a fault of a central processing unit 13 or a fault of a communication circuit, a control instruction determining means 102 outputs a start signal to a self-control instruction generating means 104. When the start signal is inputted, the self-control instruction generating means 104 outputs a self-control instruction necessary for electrifying a heater 4 to an electrification control device 103 on the basis of the result of computation of a necessary electrification time computing means 101. Moreover, a residual time computing function of computing a residual time for a midnight service power and a function of judging whether a necessary electrification time computed by the necessary electrification time computing means 101 is equal to or longer than the residual time for the midnight service power are provided. The self-control instruction is output when the necessary electrification time is equal to or longer than the residual time for the midnight discount power.</p> |
