| 摘要 |
PURPOSE:To enable not only highly accurate measurement but also the display of concn., by directly measuring the concn. of oxygen in air by using an oxygen sensor and applying A/D conversion to the output of said sensor. CONSTITUTION:The output voltage from the oxygen sensor of petroleum burning heating machinery generating the voltage corresponding to the concn. of oxygen in air is amplified by an operational amplifier 14 and converted to a digital valve by an A/D converter 15 to be stored in a memory 17 through the input circuit 16 in a post-processing apparatus 22. It is judged whether an oxygen concn. display switch 12 is turned ON or OFF and, if ON, the data stored in the memory 17 in the apparatus 22 is converted to concn. display output by CPU18 to be displayed on a display device 20 from an output circuit 19. When the switch 12 is not turned ON, CPU18 in the apparatus judges whether the measured oxygen concn. value is a prescribe one or less. When said value is the prescribed value or less, alarm output is outputted from the circuit 19 to be informed by an alarm 21. By this method, highly accurate measurement and the display of concn. can be performed. |
