PURPOSE: To eliminate a measurement error originating from an operator, to reduce measurement errors originating from a measuring instrument, and to improve measurement precision and operativity, by constituting a device of a level discriminating circuit, delay start commanding circuit, calibration start commanding circuit, salecting circuit, converting circuit, arithmetic processing part, and control part.
CONSTITUTION: The level discriminating circuit 4 does not recognize a small pulse, so it compares the set voltage VM fed from a level setter 4a with a conversion pulse 3 all the time to generate a discrimination signal 5 when the conversion pulse exceeds the set voltage VM. The delay start commanding circuit 6 counts time-series pulses 10 by an oscillator 9 under the command of the discrimination signal 5 up to the value of a delay time setter 7, thereby generating a measurement conversion signal 8. The selecting circuit 14 receives the measurement conversion signal 8 and a calibration conversion signal 12 and also receives a conversion permit signal 19 from the control part 18 and a signal from a changeover switch 13. The control part 18 sends out the conversion permit signal 19 and the selecting circuit 14 selects the measurement conversion signal 8, and sends a conversion signal to the converting circuit 16.
HAMAMOTO TETSUHISA
OKA FUMITAKA
