The Federal Agency on Technical Regulating and Metrology (Official source).
The standard covers three primary subcomponents that make up a complete heat meter: gost r 51649 2017 skachat pdf
Specifies how devices must perform under various pressures (PN) and temperatures. The Federal Agency on Technical Regulating and Metrology
Meters must meet specific accuracy classes (typically Class 2 for billing) to ensure fair commercial accounting. Measurement Ranges: Defines nominal flow ( Qpcap Q sub p ), minimum flow ( Qicap Q sub i ), and maximum flow ( Qscap Q sub s ) thresholds. gost r 51649 2017 skachat pdf