Description: Minimum NPSH for a pump achieving a specified performance at the specified rate of flow and speed (occurrence of visible cavitation, increase of noise due to cavitation, appearance of head or efficiency drop, head or efficiency drop of a given amount, etc.).; Name: NPSHR
Description: minimum NPSH-value at the pump inlet connection required to give the rated or operating performance at the specified conditions; Name: Net positive suction head required
Description: variable quantity, which is not influenced by the control but is introduced into the control system from outside with the aim of making the final controlled variable follow it in a given relationship; Name: command variable