| 摘要 |
A thermal type flowmeter (101) is provided with a sensor element (10), an output circuit (11), a storage unit (20), and an abnormality determination unit (22). The sensor element (10) has an upstream-side thermopile (1), a heater (2), and a downstream-side thermopile (3). The output circuit (11) outputs a signal representing the flow rate of a fluid on the basis of the differential voltage between the output voltage (Vu) of the upstream-side thermopile (1) and the output voltage (Vd) of the downstream-side thermopile (3). The storage unit (20) stores in advance a referential relationship in which the reference of the relationship between the voltages (Vu, Vd) is established. The abnormality determination unit (22) compares the referential relationship with the relationship between the voltage (Vu) outputted from the upstream-side thermopile (1) and the voltage (Vd) outputted from the downstream-side thermopile (3), and determines the existence of an abnormality related to the upstream-side thermopile (1) and the downstream-side thermopile (3) |
