Description: serves as a reference variable for a slave controller; Name: output variable of the controller
Description: output variable of the controlling element, which is deducted from the control difference variable and is also the input variable of the actuator; Name: controller output variable
Description: pump h(q) curve where the maximum head (peak point) and shut-off head are not coincidental, or the total head does not decline continuously as the rate of flow increases; Name: stable pump H(Q) curve