The test rig consists a centrifugal pump drives by variable speed DC motor and theclosed-loop piping system.The flow rate is controlled by a valve installed after the pressure pipe section and ismeasured by a digital flow meter.The head across the pump is measured by the pressure gauges at suction anddischarge pipe section.The power of electric motor is measured by balancing the torque arm attached to thestator which develops an equal and opposite torque to the rotor.

1)Make sure the valve is fully closed, turn on the control panel power, and then pressthe [Start] button on motor controller.2)Adjust the frequency knob on motor controller to set the motor speed at approx.2100rpm.3)Adjust the hand wheel links to fixed end of tension gauge until the marking onmoving part of tension gauge is aligned with indicator, record down the forcemeasured by tension gauge.4)Take readings from Suction Pressure gauge and Discharge Pressure gauge. Usuallythe dial of Suction Pressure gauge is oscillating, so the reading only can be estimatedbase on average value.5)Record down the flow rate displayed on digital flow meter.6)Open the valve until the Discharge Pressure gauge reading is approx. 0.3 kgf/cm2,fine tune the motor speed to initial rpm setting if necessary. Record down thereadings described in step 3) to 5).7)Repeat above test for Discharge Pressure gauge reading at 0.6, 0.9 and 1.2 kgf/cm2.8)Repeat the whole test with another motor speed setting (1800 rpm). In this test, theDischarge Pressure setting will be 0 (Fully open), 0.2, 0.4, 0.6, 0.8 and 1.0 (Fullyclose) kgf/cm2.9)When test is finished, fully close the valve, adjust the motor speed to zero and thenturn off control panel power