The modular HM 299 system allows the investigation of different machines (reciprocating machines and turbomachines). Each machine is mounted on a base plate, which can easily be fitted into the unit. It is powered by a belt drive. Hoses with quick-action couplings provide the supply lines. The unit itself includes the electric drive motor with speed control, 2 pressure vessels for the compressor experiments, a measuring tank and a supply tank for the pump experiments and a protection cover. The intake and delivery pressure, temperature, motor speed and power are measured and displayed digitally. The corresponding flow is measured indirectly and transferred to the PC data acquisition software.