CORRECTING METHOD OF OUTPUT VALUE OF PRESSURE SENSOR

PURPOSE:To correct an output value of a pressure sensor automatically on the basis of an output signal of a temperature sensor, by providing the pressure sensor and the temperature sensor in a pressure vessel and by checking up beforehand the specific relationship between temperature and pressure inside the pressure vessel. CONSTITUTION:A temperature sensor 3 is attached to an upper tube gathering 4 of a boiler body 1, and it detects an inside steam temperature and delivers an output signal thereof to a temperature detecting circuit 9 in a control unit 8. Meanwhile, a pressure sensor 2 provided in a communication tube 7 detects an inner-boiler pressure, which is converted into an output signal by a pressure detecting circuit 10 and delivered to a comparing operation circuit 11. As the result, an inner-boiler temperature signal and an inner-boiler pressure signal are subjected to a comparing operation 11. While a boiler works, a judgement on whether the sensor 2 shows an accurate output value or not can be made on the basis of the temperature signal, since the temperature and the pressure have a specific relationship between them. In the case when the output value of the sensor 2 deviates from the allowable limits set beforehand for some cause, the pressure value is corrected on the basis of the temperature signal and a pressure value after correction is displayed 12. An alarm is issued when the deviation is large enough to be included in a range of faults.