# Software for Monitoring the In-Service Efficiency of Hydraulic Pumps
## 1 Introduction
The pumps installed in different systems need to be operated safely at a low cost. Monitoring and preventive maintenance of centrifugal pumps are crucial issues to increase their reliability and diminish the costs [23; 24]. Industry 4.0 principles must be implemented in drinking water systems to provide an efficient link between the pumping units and monitoring systems so the operator can make the best decisions [25]. The software module presented in this manuscript is a basic component of this system. Our field investigations and the surveyed literature show that the only parameter that is neither monitored nor computed is the efficiency of the pumps. Even though the power factor and the efficiency of the electric motors are provided by their manufacturers, [PERSON] et al. [26] conducted extensive tests on 435 three-phase induction electric motors from 38 different manufacturers between 2015 and 2016, showing that 58% of the values measured for the power factor of the motors were lower than those reported by the manufacturer [26], and also that 55% of the measured values for the performance were lower than the values reported by the manufacturer [26]. The pump efficiency value **is ignored in practice** and many industry studies such as [7] prove that improper design and poor pump performance may affect the plant operation such as maintenance cost, downtime and loss of production. Consequently, the software implementation allows for determining the in-service efficiency of the pumps and comparing it to the value associated with the best efficiency point (BEP). The development of a robust algorithm to assess hydraulic pump efficiency is detailed in Section 2. Free software packages have been selected to implement the algorithm, ensuring its portability on any operating system. The implementation of the algorithm and the selected software packages is detailed in Section 3. Within Section 4 the application of the software module in the operating of the PCN 65/200 centrifugal pump installed in the laboratory is discussed, which allows the determination of percentage deviations of the results supplied for the full range of operation. Section 4.1 contains the available data for the PCN 65/200 centrifugal pump that have been used for the sensitivity analysis of the algorithm regarding the input values and the parameters associated with the investigated hydraulic configuration for various operating points, covering the full operating range of the pump. The sensitivity analysis allows determining the influence of the input values and the parameters associated with the hydraulic configuration over the output values of the algorithm and their ranking according to the level of percentage deviation. The results obtained with the software module implemented in the regional water supply company, AQUATIM S.A., for the monitoring of the in situ operation of the Worthington 500 LNN-775A double flux pumps of 1 MW, ensuring the water supply of Timisoara city, are shown in Section 5. The conclusions regarding the development and testing of the software module to monitor hydraulic pump efficiency are summarized in Section 6.