A locally available 4 x 4 (100 mm x 100 mm), non-self priming Centrifugal Pump as Turbine (CPAT) was evaluated at the existing Micro-Hydro Power (MHP) System at Dilaktan, Galintujah, Alfonso Castañeda, Nueva Vizcaya which originally uses a cross-flow turbine. The forebay elevation is 23 meters above the turbine. The penstock which is 41-m long and made of 4" (100 mm) diameter GI pipe is provided with two (2) gate valves located just before the turbine.

The CPAT was subjected to variable heads and flow rates by controlling the amount of water passing through it by adjusting the opening of the gate valves. Functional relationships established were Net Head vs Discharge, Net Head vs CPAT Torque, Net Head vs Shaft Rotation, Net head vs CPAT Brake Power. Pressure gauge was attached just before the CPAT to measure the pressure head. Net head is the sum of pressure head and velocity head. Actual discharge of CPAT was computed by dividing volume of container by the accumulated time in filling up the container. A prony brake dynamometer was used to measure torque that is developed in the CPAT shaft. Rotational speed of the CPAT was measured by a contact tachometer.

The regression equations of the Discharge (Qa), Shaft speed (N), Torque (T), and CPAT BrakePower (BC CPAT) versus Net Head are Qa=0.0036H O.5662 with R2= 0.95, N= 13.044+1.335H-0.0022H with R= 0.99, T= 2.0011H with R= 0.97 and BP= 0.1173H with R= 0.98, respectively. With a known value of H the value of Qa, N, T and BP can be computed using the aforementioned equations. The locally available 4" x 4" (100 mm x 100mm) CPAT was proven that it can work at different combinations of head and discharged. Also, the 4" x 4" (100mm x 100mm) CPAT can be coupled to and can successfully run a 3-kW Synchronous Generator.