OMICRON Magazine

Magazine | Issue 1 2018 Protección Control y Medición (PCM) is a leading service provider in Guatemala, providing their customers with electri- cal engineering services for primary and secondary equipment. The 12-man team specializes in the commissioning and maintenance of electrical power substations and generation plants, and has vast experience in the execution and interpretation of electrical tests on various assets. Manuel Martínez, test engineer at PCM Guatemala reports about his business, the daily challenges he faces and one recent, completely new experience that meets these challenges. Transferred responsibility ”We have to verify that each asset was tested and that the results are satisfac- tory,” explains Manuel Martínez. The responsibilities have been transferred from the operator to the service provid- er, which puts them under considerable pressure: “We have to ensure that none of the tested assets will fail and our customers will not have any unforeseen failures in their substations and power plants. We are only successful when our customers feel satisfied with their equipment and with our service.” “My typical tasks are to coordinate and execute electrical tests in the field, and afterwards to create reports for each of the performed tests. For us as a service provider, one of the biggest challenges here is to draw conclusions quickly and in the best way,” says Manuel Martínez. “Best” in this case means: The results obtained must be correct, complete and detailed enough to allow a com- prehensive condition assessment for each test object. Speed is the key The most time-consuming task is the testing of power transformers. “Within a 12-month period, we test on average about 120 transformers and auto-transformers between 1 MVA and 50 MVA, and rated from 4.16 kV to 230 kV,” states Manuel Martínez. He explains that considerable time is needed to setup the tests, re-connect between the different test jobs and for the measurement itself. “It takes for example about four hours to com- pletely test a power transformer with 69 kV and 10 MVA.” Since speed is the key in this business, PCM Guatemala requested a live dem- onstration when they discovered the new time-saving three-phase power transformer test system TESTRANO 600 on our website, which they then purchased. “We were impressed by the test system and its performance from the very first day. The device is very good, the software very user friendly and the training courses we received after buying our own device were excellent.” One impressive day of testing In April 2017, PCM Guatemala had scheduled a transformer testing job for one of their customers. Manuel Martínez was pleasantly surprised while working with TESTRANO 600: “I have been working for PCM for almost eight years now and through my work have come into contact with various devices. But I have never been able to test eleven power transformers within one day.” “We started testing at 7 o’clock in the morning and had to test power trans- formers with 10MVA and 22 kV includ- ing the de-energized tap changer (DETC),” he continues. “Numerous parameters were measured such as power/dissipation factor, capacitance, short-circuit impedance, excitation currents, turns ratio, and DC winding resistance. And in between we also had to demagnetize the transformers. But at 4:30 p.m., only seven hours later, we were finished and all eleven trans- formers were ready to be reconnected to the grid.” Manuel Martínez Electrical Test Engineer, PCM Guatemala «We are very satisfied with TESTRANO 600 – it is easy to use and saves a lot of time in making connections and carrying out measurements.» 35