For reactor design and safety purposes, the French Alternative Energies and AtomicEnergy Commission (CEA) is currently working on the implementation of a predictive transienttwo-phase flow 4-quadrant rotodynamic pump model in the CATHARE-3 code (Code forAnalysis of THermalhydraulics during an Accident of Reactor and safety Evaluation). Thispaper presents the pump model and its validation in single-phase first quadrant conditions atcomponent scale. Explanations are first given on code architecture, meshing, equations to solveand how to switch from fixed frame to rotating frame and vice versa at impeller endpoints.Then, verification results in an ideal case are compared to Euler equations. Finally, validationresults on real cases including the prediction of single-phase first quadrant steady performancecurves and the simulation of a fast startup transient are presented