ltj 7 Report post Posted January 20, 2009 For some time now we have been studying and checking NRG #40 anemometer tolerances and manufacturing processes in tremendous detail to understand what has been causing some of the sensors to intermittently underreport wind speed. Recently we reported that a vibratory mode had been identified as the cause of the slow down. As a result of our analysis and testing, we have revised the specifications of certain materials and tightened the tolerances of certain dimensions of the sensor. These improvements have eliminated the vibratory mode in test sensors in our laboratory. We have further validated these improvements in wind tunnel tests and in limited field tests. Final validation of these improvements must await the results of longer term field data which will take another 6 to eight weeks. We are confident, based upon the results of our laboratory testing, that these changes have a high potential to significantly reduce the probability that a sensor will degrade in the field. Therefore, we believe that it is appropriate to integrate these modifications into the NRG#40 immediately. As of January 5, 2009, all sensors will ship with the improvements. 7 ritaSn, japedlen, BillyVunda and 4 others reacted to this Quote Share this post Link to post Share on other sites
mariano caliva 0 Report post Posted March 10, 2009 Quote Share this post Link to post Share on other sites
mariano caliva 0 Report post Posted March 10, 2009 To the NRG Technical Support, Our company, Misibis Resort and Management, Inc. BOUGHT TWO UNITS of NRG-NOW System 50m sets of wind mast in July 2007, and another TWO units in June 2008. these units have not yet been installed until our consultant, GARRAD HASSAN, suggested that # 40c Anemometer has technical problem. In view of the above, can you replace our anemometers without costs on our part. Request your advise on this matter. please email me at mccaliva@sunwet.com.ph thanks and regards. mar caliva Philippines Quote Share this post Link to post Share on other sites
mariano caliva 0 Report post Posted March 10, 2009 To the NRG Technical Support, Erratum. Sorry my email ad is mccaliva@sunwest.com.ph. Thanks. Mar Caliva Philippines Quote Share this post Link to post Share on other sites
Julia Austin 107 Report post Posted March 11, 2009 I have forwarded your request to our sales staff so that they can arrange to send you some replacement sensors. Quote Share this post Link to post Share on other sites
Erick Castro 0 Report post Posted March 31, 2009 Hi, We bought 10 kits of anemometers from a sale representant in Brazil. Five (5) towers already were installed, but there are others five (5) not installed yet. Can you replace this anemometers not used yet? Are there costs of shipment to do this? Quote Share this post Link to post Share on other sites
Julia Austin 107 Report post Posted March 31, 2009 We would be happy to replace any anemometers still under warranty free of charge (free shipping, too). Please contact your NRG salesperson for assistance. Quote Share this post Link to post Share on other sites
Erick Castro 0 Report post Posted April 1, 2009 My kits contains #40C. The replacement will be for a updated #40C or for #40H? Otherwhise, Is the #40H a update for #40C or just other anemometer kind? Thanks, Erick. Quote Share this post Link to post Share on other sites
Julia Austin 107 Report post Posted April 1, 2009 Hello, Erick - The #40H is NOT the same sensor as the #40C. The #40H Hall Effect anemometer requires power and provides a square wave output signal. The #40C provides a self-generated AC sine wave output signal. Quote Share this post Link to post Share on other sites
Erick Castro 0 Report post Posted April 1, 2009 Thanks Julia, So I was thinking correctly. My point now is: Does #40H sensor have presented vibratory mode problem too? Quote Share this post Link to post Share on other sites
Julia Austin 107 Report post Posted April 1, 2009 #40H anemometers are also potentially affected by the vibratory mode problem. Quote Share this post Link to post Share on other sites