Criteria about third party sensors in Third Party Sensors Posted November 1, 2013 · Report reply NRGreleased the NRG Class1 sensor last year, which contains an innovative lowfriction ball bearing design providing very good responsecharacteristics. In fact, the NRG Class1 is a true ?class 1? sensor at avery attractive price. The NRG Class 1kept the rugged cup design of the NRG #40C anemometer, as well as the proven shieldedsignal pick-up mechanism. Icannot say for certain that other sensors fail more easily than the rugged coildesign of the NRG, as your experience suggests. Both the NRG Class1 and the NRGWindsensor P2546C use a self generating coil and magnet arrangement, requiringfewer wires and no power from the data logger. Another great benefit of such a signal arrangement is that even under adirect lightning strike, the sensor will not fail as a short (signal coils failas an open circuit), and the remaining channels keep logging data until you canvisit the site. The WindSensor has excellentfirst class performance characteristics, the lowest distance constant of anycup anemometer in existence, as well as superior off shore capability. Youcan read about the NRG Class 1 classification in the paper ?Characterization and Classification of the NRG Class 1 Anemometerfor IEC 61400-12-1 Compliance? found on the NRG Class 1 product page.