HELP FOR CALCULATING TOTAL HEAD WITH PRESSURE READINGS AND PUMP POWER WITH AMP READINGS

Applets are programs based on the java language that are designed to run on your computer using the Java Run Time environment.

Calculating total head with pressure measurements

The total head can be calculated based on this formula which is the method proposed by the Hydraulic Institute www.pumps.org. Therefore the results that you get using this method will be comparable to the results obtained by the pump manufacturer. That is for the same pressures and flow rates you will obtain the same value for total head as the manufacturer.

in US units

in metric units

The velocity calculations are based on this formula:

in US units

in metric units

Variable definitions:

pd: pressure at the pump outlet;

ps: pressure at the pump inlet;

zd: height between the pressure gauge at the pump outlet with respect to the pump centerline;

zs: height between the pressure gauge at the pump inlet with respect to the pump centerline;

vd: fluid velocity at the pump outlet;

vs: fluid velocity at the pump inlet;

q: flow rate through the pump;

D: diameter of the outlet or inlet of the pump;

Hp: total head of the pump.

Calculating the power consumed by the pump based on motor current readings

The power consumed can be calculated with this formula:

in US units

in metric units

The motor efficiency (eff) and power factor (P.F.) will have values that depend on the motor construction and the actual load in operation. This information is available from the motor manufacturer. The following two charts are the results of an investigation by the US Department of Energy and provide representative values for these parameters.

The applet is designed to be used in English or French.

ENJOY!