LIDARs and Radiometer back at NWTC

On Monday September 9th WC49, WC61, WC68, and the CU Radiometer we re-deployed at the NWTC.

Instrument	NWTC Location	Latitude (dd.ddddd N)	Longitude (dd.ddddd W)
Radiometer	4.1 Pad	39.91058	105.22350
WC49	3.1 Pad	39.91122	105.22605
WC61	4.1 Pad	39.91061	105.22349
WC68	4.0 Pad	39.91194	105.22252

The radiometer shipping box is located in the 4.1 data shed.  All of the LIDAR shipping boxes and wooden field stands are stored in the 3.1 data shed.

Data outage for Windcube 68

WC68 was down from 5/2 til 5/17 due to a tripped GFCI outlet.  I think the reason for the tripped GFCI was due to water infiltrating the power chord that runs from the windcube to the power converter.  There was a gash in the external insulation of this line and there was obvious copper corrosion inside of the insulation.  I did not see any other damage to the line.  I was able to cut out the bad section of wire and replace the weather proof connector.  The system seems to be operating normally now.

Power Loss

This morning at the NWTC, both the NCAR and CU windcubes shutdown due to a loss of grid power.

It looks like the NCAR windcube was offline from ~13:38 until 14:51:20 on April 23, 2013 UTC time.  As of 19:30 the NCAR windcube was recording below the CNR threshold for all heights.


The CU windcube was down from ~13:38 til 14:51:51 on April 23, 2013 UTC time.  As of 19:30 the CU windcube was recording strong CNR values at all heights!

CU windcube back online

Power to the 4.0 pad has been replaced and the CU windcube is back up and running.

I also ran a diagnostic test for Welly at NRG on the NCAR windcube.  The window was covered from about 11:50 MDT to 15:20 MDT.  Later in the day I noticed that the NCAR system was 1 hour ahead of UTC which is likely due to the daylight saving time shift of the GMT timezone.

In addition to the diagnostic test I refilled the NCAR water container and gave the windcube window a good cleaning with vinegar to remove mineral deposit build up.  The removal of the build up on the window greatly improved the CNR for the north and east retrievals.

Stage Motor Replaced!

This afternoon I met up with Welly Cobden from NRG to replace the stage motor on the CU windcube.  The process was pretty straight forward and we took care of the physical replacement.

I had the opportunity to learn a great deal about the system and how it works.  Some of the important/interesting things that stand out to me are:

• The laser beam is about the size of a dime at the window and converges to about half that diameter around a height of 80-100 m.  
• The laser is turned off when the "windsoft" software is closed, or even if the stop button is clicked to stop the measurement.  This ensures that the system is eye safe even with the very low risk of exposure with the north side door open.  The major laser hazard exists at the blue fiber on the south side door; at the fiber laser power is concentrated enough to create an extreme hazard to your vision.
• NRG finds that the best wiper solution is diluted wiper fluid.  It reduces mineral buildup on the windcube window.
• We should be able to use the Verizon SIM card in the existing internal windcube modem.  We just need to find the right system settings.  I am hopeful that this will reduce/eliminate our external connection outages.
• The internal GPS should work, but it is not being consistent.  We should try updating the driver.
• When the weather gets cold the stage motors often start to have trouble due to the internal grease becoming more viscous.  Adding some insulation to the exterior of the box during cold weather might help maintain the life of the motor.
• Welly is not sure what is causing the extreme wind speed records in the NCAR (and less often the CU) windcube.  It is possible that the system is detecting a higher than real CNR because of poor internal grounding issues, thus some records are kept instead of being thrown out.

Wipers are kaput

On today's visit to the NWTC I took a look insidethe CU windcube to double check the connection for the stage motor.  I first noticed that the wiper motor fuse was blown, so that will need to be replaced; I did not notice anything else out of place.  I closed the system up and turned the system on.  The stage began rotating, but I did not get a chance to see if it ceased again because the protective covers for the extension cords had been removed.

The NCAR windcube wiper motor started to work, but got stuck in the middle of a wipe which was obscuring the south and west directions.

CU Windcube Motor Issues

Some time around Tuesday February 19th or Wednesday the 20th the drive motor on the CU windcube failed and compromised the recorded data (exact times to be determined).  The unit recorded data sporadically for the next couple of days, but the laser was pointed south for all of those measurements.

The unit will be shipped to NRG for repair and system upgrade.




Update:  Looking at the .RTD files indicates that the windcube records different position directions (0 90 180 270 0 90 180 270 ...) regardless of the actual head position.