Abstract: Embodiments of the present application provide a status detection method and apparatus for a filter. The filter filters a fluid in a sealed channel. At least a pressure sensor is further provided downstream of the filter in the sealed channel. The method includes: if a fluid flowing through a filter in a sealed channel is controlled to have a first flow rate, then acquiring a first pressure value measured by a pressure sensor; if the fluid flowing through the filter in the sealed channel is controlled to have a second flow rate, then acquiring a second pressure value measured by the pressure sensor; and determining a status of the filter according to a difference between the first pressure value and the second pressure value. Therefore, detection of the status of the filter is achieved, and an operator is prompted to maintain/replace the filter in time. In addition, an existing component can be used, so that applicability is high and detection costs are low.

Abstract: A sensor for redundantly measuring gas flow has a housing suitable for being interposed in a gas flow conduit. The housing has an orifice through which the gas to be measured flows. A gas flow measuring, hot wire anemometer is positioned in the housing proximate to the orifice for providing a first measurement of the gas flow in the conduit. A first absolute pressure sensor measures gas pressure downstream of the orifice. The first pressure sensor may provide pressure compensation to the anemometer. A second absolute pressure sensor measures gas pressure upstream of the orifice. The first pressure sensor may be further used with the second pressure sensor to obtain a differential pressure measurement providing a further measurement of the gas flow in the conduit that is redundant to that of the anemometer.