In complex systems, pumps can be connected in series or in parallel. In serial operation the heads of the pumps are added and in parallel operation the flow rates (capacities) of the pumps are added. 

  The experimental unit provides the determination of the characteristic behavior for single operation and interaction of two pumps.

  HM 284 features a closed water circuit with a water tank and two centrifugal pumps with drive motors. The speed of one motor is variably adjustable by a frequency converter. The other pump is fitted with a motor with fixed speed, this pump can be added to the system. The impellers of both pumps are mounted in transparent housings and can be observed during operation.  Valves enable to easily switch change between single pump, series or parallel pump operation. The system behaviour is analyzed with the aid of a valve in the delivery pipe adjusting the flow resistance.

  The experimental unit is fitted with sensors for pressure and flow rate.

  The microprocessor-based measuring technique is well protected in the housing. All the advantages of software-supported experiments and evaluation are offered by the GUNT software and the microprocessor. The connection to a PC is made by USB.

  The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

- operating behaviour of centrifugal pumps
  * single pump operation
  * series pump operation
  * parallel pump operation
- recording of pump curves
- determination of pump efficiencies

- recording of system characteristic