Legal analysis
If the flow rate is far below the minimum flow rate to ensure accuracy, there will be no output (such as vortex flowmeter) or the output signal will be cut off as a small signal (such as differential pressure flowmeter), which is unfavorable and unfair to suppliers. In order to prevent the loss of benefits, for a specific set of thermal energy metering equipment, the supply and demand sides often agree that a certain flow value is the "agreed lower limit flow" according to the flow measurement range and the achievable range, and agree that if the actual flow is less than the agreed value, it will be charged according to the lower limit flow. The metrological administrative department of the people's government at or above the county level may set up metrological verification institutions according to needs, or authorize metrological verification institutions of other units to perform compulsory verification and other verification and testing tasks. Personnel who perform the verification and testing tasks specified in the preceding paragraph must pass the examination. This function is usually realized in the flow display instrument. The metrological administrative department of the local people's government at or above the county level shall, according to the needs of the local area, establish public standard instruments of measurement, which shall be used after passing the examination presided over by the metrological administrative department of the people's government at a higher level. Enterprises and institutions may, as required, establish standards of measurement for their own use, and the highest standards of measurement shall be used after passing the examination presided over by the metrological administrative department of the relevant people's government. Metrological verification shall be carried out on site in accordance with the principle of economy and rationality. Metrological verification must be carried out in accordance with the national metrological verification system table. The national metrological verification system table shall be formulated by the metrological administrative department of the State Council.
legal ground
Article 20 of the Measures for the Administration of Invoices in People's Republic of China (PRC) _ When units and individuals sell goods, provide services and engage in other business activities to collect money, the payee shall issue invoices to the payer; Under special circumstances, the payer will issue an invoice to the payee.