A ball valve that is equipped with an actuator that manipulates a stream of fluid in the response to a signal from an external sensing element and with input of energy from an external source.
A dynamic pump that contains impellers provided with vanes to generate centrifugal force to achieve the required pressure head.
A physical object that is a general term covering switching devices and their combination with associated control, measuring, protective and regulating equipment, also assemblies of such devices and equipment with associated interconnections, accessories, enclosures and supporting structures.