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#189 vibration problem in #40 anemometer

Posted by techfe on 21 May 2009 - 04:55 PM

We have had vibration problems in #40 anemometers (serials 37538,37534,37535 and other 3 of them) all bought in 2007 and 2008. How warranty works?


Could you please tell me what to do?


 


 


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#104 Could you elaborate on recommendations for how to use data from masts with co...

Posted by Julia Austin on 18 December 2008 - 10:00 AM

Q: Could you elaborate on recommendations for how to use data from masts with corrupted sensors?



A: It is best to compare the ten-minute average of two sensors that are mounted at the same height. By looking at the difference (or ratio) between these two sensors, it can be determined whether one or both are experiencing excessive drag. (See slides 8 and 10 in the presentation for a visual depiction.) Typical data quality checks can then be used to filter the data. If unsure, it is best to consult an expert in data analysis.


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#100 What is your recommendation on parallel installs other manufacturers' sensors...

Posted by Julia Austin on 18 December 2008 - 09:56 AM

Q: What is your recommendation on parallel installs other manufacturers' sensors alongside the 40C to compare the data (i.e. at what height and direction to install new, third party sensors)?



A: There is no consensus on best practice as it relates to tower configuration; preferences will vary depending on priorities. Some of our customers pair different anemometers with #40Cs at the same level. The height and direction is typically dictated by site conditions and prevailing winds. 


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#99 Do you have an estimated timeline for when field testing and reengineering [s...

Posted by Julia Austin on 18 December 2008 - 09:56 AM

Q: Do you have an estimated timeline for when field testing and reengineering [sic] will be complete?



A: We can?t provide specific timelines. Our validation criteria require that we collect data from 50 pairs of anemometers for eight weeks. Only when we have sufficient data, and consensus that the sensors are performing up to pre-2006 standards, will we form conclusions and move ahead. There is a short amount of time on either side of those eight weeks to complete engineering activities, deploy sensors, and ramp up manufacturing.


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#98 Has this problem been seen on both tubular and lattice towers? Also, has this...

Posted by Julia Austin on 18 December 2008 - 09:55 AM

Q: Has this problem been seen on both tubular and lattice towers? Also, has this problem been seen on varying boom lengths/types?


A: We have seen sensor dragging on both tubular and lattice towers, and on booms of various geometries and manufacturers.


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#97 Could this problem be found in the non-calibrated #40 anemometers?

Posted by Julia Austin on 18 December 2008 - 09:54 AM

Q: Could this problem be found in the non-calibrated #40 anemometers? 



A: Yes, the same vibratory mode could occur in non-calibrated #40?s manufactured in 2006.


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#93 How do we determine if the data we have collected is valid?

Posted by Julia Austin on 18 December 2008 - 09:21 AM

Q: How do we determine if the data we have collected is valid?



A: Comparing two sensors mounted at the same level by taking the difference (or ratio) of the ten-minute average readings is the simplest method. The two sensor readings should track fairly well, but if one sensor is in this vibratory mode, then the difference (or ratio) between the two will diverge. Keep in mind that two sensors at the same level may not track exactly the same due to other factors (e.g. wind regime, mounting configuration, site terrain, etc). The level of scatter should be excessive. If unsure, it is always best to consult a data analysis expert.


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#91 Once an anemometer shows signs of dragging, how often will it go into the vib...

Posted by Julia Austin on 18 December 2008 - 09:11 AM

Q: Once an anemometer shows signs of dragging, how often will it go into the vibratory mode? 30% of the time in 5-10m/s wind? 70%?


A: An anemometer susceptible to the vibratory mode will tend to switch into its normal mode at higher wind speeds (above 10 m/s) and at very low wind speeds (below 5 m/s). In the 5-10 m/s range it will vary by sensor and its environment. In answer to this specific question, we don't have a basis by which to identify a typical percentage. We estimate that 20-30% of all sensors manufactured after 2006 are affected by this issue.


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#235 NRG #40 anemometers

Posted by Steve_Heidra on 03 August 2009 - 12:11 PM

 I have just tested two uncalibrated #40 anemometers and a calibrated #40 anemometer in a wind tunnel under identical conditions.  I was really concerned about the results and tried to make contact with NRG with no response as yet.  I tested between 1 and 20 m/s.  Above 5 m/s the results showed reasonable agreement.  Below 5 m/s the new calibrated #40 show significant sticking.  Extrapolating the above 5m/s calibrated results below 5 m/s indicates the uncalibrated #40 anemometers (used for 8 months) showed no noticeable sticking down to 1 m/s, but rather overspeeded by more than 1 m/s.  When used in an MCP analysis for a low wind speed site these results are of a high concern.  COME ON NRG.  We need some answers.  I feel I might as well buy some cheaper product or go for a product which you can trust. 


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#186 White Paper: "Investigation of the NRG #40 Anemometer Slowdown" by S...

Posted by Julia Austin on 14 May 2009 - 01:31 PM

AWEA Windpower 2009 Paper V5-11-09.pdf

Paper submitted for AWEA Windpower 2009 Conference, 4 - 7 May 2009, Chicago, IL, USA

"Investigation of the NRG #40 Anemometer Slowdown"

by Steven H. Clark, Principal Investigator

 Owen Clay, John A. Goglia, Timothy R. Hoopes, Lawrence T. Jacobs, R. Paul Smith


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#1704 Download partial files (yes or no)

Posted by ibrochim on 27 May 2016 - 11:57 AM

Dear all,

 

I have a problem with iPack setting, in tab "settings" there's a choice for "Download partial files". When i choose (thicked) "yes" and i press "call now" email succeed sent but when i change with "no" and i press "call now", error 2421 appears and disconnecting suddenly.

what should i do?. Thank you

 

regards


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#164 what is vibratory mode?

Posted by ROHAN JADHAV on 22 April 2009 - 03:31 PM

 What do you mean exactly when saying anemometer is in vibratory mode?

 Regards


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#157 Link to slides from last webinar presentation

Posted by ColinMurray on 15 April 2009 - 11:23 PM

Is there a link to the slides from the last webinar presentation?

Regards,

Colin Murray


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#118 Update on #40C Sensor Shipments

Posted by ltj on 20 January 2009 - 01:00 PM


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.


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#116 Icefree3 sensors

Posted by GemmaAllen on 16 January 2009 - 07:06 AM

Is it possible that your Icefree3 anemometer is affected by the vibratory mode issue?


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#103 Can we get a transcript and copy of this presentation?

Posted by Julia Austin on 18 December 2008 - 09:58 AM

Q: Can we get a transcript and copy of this presentation?



A: Both are available on our tech forum, http://forum.nrgsystems.com/forums


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#240 Vibratory Mode Anemometer Replacement

Posted by fabianb on 17 August 2009 - 07:29 PM

Good afternoon,

Does NRG have a official position about what NRG#40C anemometers that could be affected by the vibratory mode will be replaced and what will be the procedure for this replacement?

- Should the customers send data to NRG in order to prove that their anemometers are presenting the vibratory mode?

- Should the customers return their anemometers to NRG?

- What about the unsued anemometers?

- Should the anemometers be within their period of warranty in order to be replaced?

- Which costs are covered by NRG and which by the customers?

 Thanks in advance for your answers.

 


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#185 AWEA Windpower 2009 Presentation "Investigation of the NRG #40 Anemometer...

Posted by Julia Austin on 14 May 2009 - 01:25 PM

AWEA Windpower 2009 Presentation V5-12-09.pdf 

"Investigation of the NRG #40 Anemometer Slowdown"

Presented 7 May 2009 by Steven Clark, Mechanical Engineer, NRG Systems, Inc.

AWEA WINDPOWER Conference and Exhibition 2009, Chicago, IL


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#1708 Looking for silent install commands for SDR

Posted by carloswlkr on 12 July 2016 - 06:00 PM

I would like to install SDR on several user machines that are in remote locations, and rather than logging in remotely, would like to deploy the package over the network. I would need to do a silent install of the software. are there any command line parameters available for a silent install? Is there an MSI package available? 

 

Thanks!


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#101 What is the magnitude of any planned cost increase per sensor for a 'revised'...

Posted by Julia Austin on 18 December 2008 - 09:57 AM

Q: What is the magnitude of any planned cost increase per sensor for a 'revised' sensor?



A: There is no planned cost increase.


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