| 摘要 |
PURPOSE:To obtain the stabilized output for a long period by using a CPU based on the data of a span drift which has been empirically obtained beforehand, operating the compensating amount for the drift with respect to the elapsed time by a program, and compensating the span drift. CONSTITUTION:The detected signal of an A/D converter circuit 9 is inputted from an I/O 10a in a CPU 10d. Then, a span coefficient and parameters which are stored in a RAM 10c and used in operation are automatically changed with the elapse of time by a program stored in a ROM 10b with respect to the signal from time to time. The rate of the change is changed. Thus, the concentration of residual chlorine at this time is operated. Namely, the detected signal is changed from time to time with the elapse of time based on the span coefficient, the parameters and the program, and the rate of change is changed. Thus, the compensating amount of a drift is operated with respect to the elapsed time. The operation for compensating the span drift can be performed. Thus, the stabilized output for a long period can be obtained. |
