Mass flow controllers and methods for controlling mass flow controllers are disclosed. A method includes providing a gas through a thermal mass flow sensor of the mass flow controller and processing a flow sensor signal from the thermal mass flow sensor of the mass flow controller to produce a measured flow signal. The measured flow signal is corrected to produce a corrected flow signal by gradually changing non-linearity correction to the measured flow signal when a flow rate of the gas changes. A valve of the mass flow controller is controlled using the corrected flow signal and a setpoint signal.

Provided is a physical quantity measurement device capable of reducing a frequency analysis error of a gas flow rate as compared with the related art. A physical quantity measurement device 20 includes a flow rate sensor 205 and a signal processing unit 260. The signal processing unit 260 has a buffer 261, an offset adjustment unit 262, a gain calculation unit 263, a correction calculation unit 264, and a frequency analysis unit 265. The buffer 261 stores a flow rate data based on an output signal of the flow rate sensor 205 for a predetermined period. The offset adjustment unit 262 adjusts the zero point of the flow rate waveform. The gain calculation unit 263 calculates a correction gain of the flow rate waveform whose zero point has been adjusted. The correction calculation unit 264 performs the correction by multiplying the flow rate waveform whose zero point has been adjusted by the correction gain. The frequency analysis unit 265 performs a frequency analysis calculation of the corrected flow rate waveform and stores the data obtained by the calculation in the buffer 261. The gain calculation unit 263 calculates the correction gain at which the overflow does not occur in the frequency analysis unit 265.

Techniques detect a low gas-pressure condition within a region without the use of pressure sensors. In an example, gas usage at a service site is disaggregated to show use by individual appliances. A flowrate of gas at an appliance (e.g., a gas hot water tank) having a generally fixed-rate of gas-consumption is determined. Based at least in part on the flowrate of gas at the appliance, and an historical gas flowrate at that appliance, it is determined if gas pressure at the service site is lower than expected. In an example, failure of the appliance to use its typical fixed-flowrate may indicate low gas pressure at the service site. Information is obtained from a second gas meter at a second service site. Based on the gas pressure at the first and second service sites being lower than expected, a low gas pressure situation may exist in a regional area.

Techniques for using data indicating if a gas regulator supplying gas at a regulated pressure to a gas meter (e.g., the gas meter of a house or business) within a gas distribution system has one or more lock-up failure events or venting events, wherein gas is vented to the atmosphere. The data may identify the identity of gas regulators at which the lock-up failure events or venting events occurred. Based at least in part on the identified gas regulators, a number of gas regulators having at least one of lock-up failure events or venting events that are connected to a same gas supply line may be identified. If the number of gas regulators having at least one of lock-up failure events or venting events on the identified gas supply line exceeds a threshold number this may indicate the presence of debris in the gas supply. Remedial steps may be taken, and the situation may be monitored and reassessed.

Techniques determine if an appliance having a fixed-rate of gas-consumption is degrading over time. In one example, a flowrate of gas at a service site is obtained. The flowrate of gas is disaggregated to obtain a flowrate of gas corresponding to an appliance having a generally fixed-rate of gas-consumption. The flowrate of gas of the appliance is compared to historical gas consumption by the appliance. Based at least in part on the comparing, it may be determined that performance of the appliance has changed over time. For example, the gas consumption of a hot water tank may increase due to mineral build-up in the bottom of the tank. Responsive to the determined degradation of the appliance, warnings may be sent, repairs may be made, and/or appliance(s) may be replaced.

Aspects generally relate to methods, systems, and apparatus for conducting a calibration operation for a plurality of mass flow controllers (MFCs) of a substrate processing system. In one aspect, a corrected flow curve is created for a range of target flow rates across a plurality of setpoints. In one implementation, a method of conducting a calibration operation for a plurality of mass flow controllers (MFCs) of a substrate processing system includes prioritizing the plurality of MFCs for the calibration operation. The prioritizing includes determining an operation time for each MFC of the plurality of MFCs, and ranking the plurality of MFCs in a rank list according to the operation time for each MFC. The method includes conducting the calibration operation for the plurality of MFCs according to the rank list and during an idle time for the substrate processing system.

An ageing and dust detection system, comprising: a data collection unit configured to collect a plurality of parameters of a gas meter; and a processing unit, configured to: receive the plurality of the parameters of the gas meter; calculate a numerical value of the plurality of the parameters; compare the calculated numerical value of the plurality of the parameters with a corresponding predefined higher range of values and a predefined lower range of values for the plurality of parameters; determine a reason of a fault in the gas meter based on the compared values, wherein the reason of the fault in the gas meter is at least one of, a presence of a dust, an ageing of the gas meter, or a combination thereof.

Embodiments of a portable verification system (5) can move from one in-field gas flow meter location to another and temporarily connect downstream of a main pipeline's meter run or station. A control valve (19) of the portable verification system (5) allows volume measurement at different flow velocities to be verified. In some embodiments, the portable verification system (5) is connected to the meter run (13) and the main pipeline by a corresponding slip or linearly adjustable pipeline section (30/70). This section (30/70) can extend horizontally and vertically, as well as swivel to provide versatility when connecting in the field. Adaptor fittings may be used to connect the system (5) to the meter run (13) and main pipeline or a quick connect/disconnect (105) may be used. Downtime is limited to the time required to complete a circuit between the meter run, portable verification system (5), and main pipeline.

A fluid monitoring system is provided, which includes at least one fluid vibration sensing unit to provide at least one fluid vibration signal from at least one location on a measuring chamber of a meter to be monitored. The system also includes one or more display units, and a control unit configured to be coupled to the at least one fluid vibration sensing unit and the one or more display units. The control unit is configured to detect a condition from the respective location using the at least one fluid vibration sensing unit and communicate to at least one or more display units to provide a display of the condition. A meter with a fluid monitoring system is also provided.

A fluid monitoring system is provided, which includes at least one fluid vibration sensing unit to provide at least one fluid vibration signal from at least one location on a measuring chamber of a meter to be monitored. The system also includes one or more display units, and a control unit configured to be coupled to the at least one fluid vibration sensing unit and the one or more display units. The control unit is configured to detect a condition from the respective location using the at least one fluid vibration sensing unit and communicate to at least one or more display units to provide a display of the condition. A meter with a fluid monitoring system is also provided.