| 摘要 |
PURPOSE:To easily make a correction or inspection without interrupting the measurement of a flow rate by correcting the zero point and span of a flow rate signal converting circuit part and confirming a set initial value through intermittent sampling processing with simple circuit constitution. CONSTITUTION:When a correction or test command is inputted from an input setter 16, an MPU 12 reads it and adds interruption processing by a test signal to a normal routine. The flow rate measurement processing in this period is the 1st intermittent sampling processing and a comparison with the last result is made; when specific variation width is obtained, an output is sent out directly and when the width is exceeded, the output is sent out after movement mean processing. The timing signal of this processing is sent as S4 from the MPU 12 to semiconductor switches 19a and 19b and connected to an incorporated correcting signal generating circuit 18. A signal equivalent to a flow rate signal is sent out of the circuit 18 to a circuit part of a converter to be corrected in synchronism with an exciting current direction control signal S1. A correction result is outputted to a display device 15'. Thus, a correction or inspection is easily made without turning off the power supply.
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