antud voomahu juures veearvesti olemasolust põhjustatud vältimatu rõhu vähenemine torus, irrecoverable decrease in pressure, at a given flow rate, caused by the presence of the water meter in the pipeline, non-recoverable pressure drop caused by the presence of the meter in the pipeline, non-recoverable pressure drop caused by the presence of the turbine meter in the conduit, difference of pressure between two positions in the flow path, rõhu erinevus voo kahe asukoha vahel, irrecoverable pressure loss caused by the presence of a primary device in the conduit