SOUND PRESSURE LEVEL MEASURING TYPE FLUID LEAK DETECTOR

摘要

PURPOSE:To enable the calibration of a microphone for detection through remote control, by transmitting different levels of calibration signals to a speaker added to the microphone for detection as the calibration sound source. CONSTITUTION:Different levels of calibration signal 9 outputted from a signal generation circuit 10 set on a cooling material leak instrumentation panel 5 are transmitted to a speaker 8 added to the microphone 3 arranged in an inlet tube insulating box 2 of a nuclear reactor container 1 to transmit a reference sound pressure to the microphone 3. The microphone 3 receiving the reference sound pressure transmits a sound pressure signal 4 of an electrical signal to a signal amplification circuit 6 to be indicated on a voltmeter 7. An operator checks the indication of the voltmeter 7 for coincidence with a prescribed value. When it differs from the value, a resistance attenuator 26 added to the signal amplification circuit 6 is adjusted to eliminate said difference and thus the output value of the signal amplifier 6 is calibrated.