Davis Vantage Pro 2 - no readings from anemometer and wind direction

[Galmpton_Miller]

Hi group
I have been getting no wind speed or direction readings from my weather station.
I have checked for corrosion / muck on the connector from the anemometer into the base, this looks fine.

As a first port of call, I'd like to check the anemometer and wind direction "senders" as it looks like these will be the easiest things to do.
Any ideas on how to check them? My electronics is not too bad and I have DMMs and a 'scope.
The console is not giving a low battery warning (but I guess I should measure the internal battery volts to make sure).

Anything else that is easy to check?

Thanks in advance

Stuart

[elagache]

Dear Stuart and WeatherCat station troubleshooters,

I have been getting no wind speed or direction readings from my weather station.

. . .

As a first port of call, I'd like to check the anemometer and wind direction "senders" as it looks like these will be the easiest things to do.
Any ideas on how to check them? My electronics is not too bad and I have DMMs and a 'scope.
The console is not giving a low battery warning (but I guess I should measure the internal battery volts to make sure).

I assume that WeatherCat isn't reporting any sensor errors - correct?  If it was that might be a clue to your problem.  How old is your station?

Unfortunately, I know of anybody on this forum that has dissected a Davis station and attempted to understand what the station is doing electronically.

Certainly, you could give the Davis Tech Support people a try.  The phone number is:

1 (510) 732-7814

You should be able to get from them some quick tests that you could perform.  It is best to call because Davis isn't very good about answering tech support emails.

If you are bold and aren't afraid of a rowdy bunch, you might try posting a question on the WX-Forum:

http://www.wxforum.net/

You'll find the sort of guys who have taken their David stations apart and know what to try and what will fry your instruments.

Best of luck getting your anemometer back on line!

Cheers, Edouard

[Bull Winkus]

This is straight from the manual for Vantage Pro 2 (Hope it helps!):

Troubleshooting

 ?The wind cups are spinning but my console displays 0 mph.?

The signal from the wind cups may not be making it back to the display. Check your cables for visible nicks and cuts. Look for corrosion in the WIND connector on the SIM and on splices in the cable. If using an extension cable, remove it and test using only the anemometer cable. Contact Technical Support and ask for a wind test cable if the problem has not been resolved.
Note:
If the anemometer is sending no data, the wind display indicates 0 speed and a north direction.

 ?The wind direction is stuck on north, or displays dashes.?

It is likely that there is a short somewhere between the wind vane and the display.
Check the cables for visible nicks and cuts. Look for corrosion in the ?WIND? jack on the SIM and on splices in the cable (if any). If possible, remove any extensions and try it with the anemometer cable only. If none of these steps get the wind direction working, contact Technical Support and ask for a wind test cable.

 ?The wind cups don?t spin or don?t spin as fast as they should.?

The anemometer may be located where wind is blocked by something, or there may be friction interfering with the cups? rotation. Remove the wind cups (loosen the set screw) and clear out any bugs or debris. Turn the shaft the cups rotate on. If it feels gritty or stiff, contact Davis Technical Support.
Note:
Do not lubricate the shaft or bearings in any way. When replacing the cups, make sure they are not rubbing against any part of the anemometer head.

 ?Readings aren?t what I expected them to be.?

Comparing data from your ISS to measurements from TV, radio, newspapers, or a neighbor is NOT a valid method of verifying your readings. Readings can vary considerably over short distances. How you site the ISS and anemometer can also make a big difference. If you have questions, contact Technical Support.

Contacting Davis Technical Support

Note:
For questions about installing or operating your Solar Power Kit, please contact Davis Technical Support. We?ll be glad to help.

Online www.davisnet.com

See the Weather Support section for copies of user manuals, product specifications, application notes, software updates, and more.

E-mail support@davisnet.com Telephone (510) 732-7814
Monday - Friday, 7:00 a.m. - 5:30 p.m. Pacific Time.

[HantaYo]

Here is the recent response I received from Davis in regards to no wind directions being received by the stations:

Here are a few things you could try to get it working:

1)     Remove the wind cups and then put them back on making sure to push all the way up before tightening.

2)     Check the cable between the anemometer and the transmitter, making sure that the cable has not been damaged.

If still not working it could be a problem with the anemometer or the transmitter module. We would need to send you a free test cable to determine which is the problem. Can you email me your address so that we can send a test cable out to you along with the instruction

[Bull Winkus]

Does this help?

[Galmpton_Miller]

Hi everyone
I really appreciate all the suggestions and the circuit schematic, thank you!

My station is 3 or 4 years old (at a guess). I has been fine to date.
The cups and the wind direction pointer seem to be operating normally.
The console is not giving any errors.

It looks like I need to get the pole down to look close up at the anemometer and direction pointer and do a test on the cable from the anemometer to the station.

I plan on doing this over the weekend, so will keep you posted.

Cheers

Stuart

[Galmpton_Miller]

Hi all
It was a nice day today, so I got the anemometer pole down and had a look at the cable ties holding the cable to the pole - they were fine, a little degraded due to UV, but the cable had not moved. There was no obvious sign of cable damage from the anemometer to the ISS.
Removed the anemometer from the pole, the cups were freely rotating and the wind direction vane was also freely rotating but felt slightly stiffer than the cups.

I used a continuity tester and tested the continuity according to the schematic Bull Winkus posted earlier (really useful, thanks Bull!).
I got a short circuit from Red to Black (across the wind speed switch) - this was not affected by the position of the cups, so it looks like the switch is permanently closed. This switch is a fixed reed switch that is controlled by a magnet rotating with the cups. As the magnet passes over the switch, it (I assume) closes. I took a photo of the reed switch. I am not sure whether it moves from open to closed as the magnet passes over the reed switch, or from closed to open - the schematic implies open to closed; but either way the short did not change as I rotated the cups.

On the wind direction side, I measured a fixed resistance (about 22 K Ohms) from Yellow to Red and a variable resistance from Red to Green.
These were all measured at the ISS connector, so through the 12 metres or so of cable.
I assumed from this that the wind direction element should be working fine.

I removed the vane and cups to see if there was an obvious reason for the short. Each is secured to the relevant shaft with a grub screw - removed using a 0.050 inch hex key, which also fits the 2 screws holding the plastic housing to the bent aluminium shaft.
If you do this, remember to mark the alignment of the shaft of the potentiometer with the housing before carefully removing the wind direction vane or the wind direction will be incorrectly reported.

There is not much to see to be honest. The potentiometer is "heat staked" in to the housing so cannot be easily removed, see the photo.

The reed switch is attached to what looks like a small pcb, but I could not remove it from the housing.

Essentially, this unit is not easily repairable. I think it would be tricky to assemble in the factory, too!

I suspect the reed switch is short circuited, but can't remove it to see (and replace it). I suspect this short affects the wind direction circuit, making this fail to operate (but this is just a guess). Hence no reporting of wind speed and direction. 
To be thorough, I should inspect the ISS connector and make sure it is delivering the 2.5 V to the anemometer unit, as the schematic shows.  I am wary of doing this as it would be very easy to short the connector pins.

A new anemometer unit, here in the UK is about ?160! I found a B-stock (opened box) unit in Germany on E-bay for about half this!

I guess this one "one of those things", as the method used for wind speed and direction could not be simpler. Very frustrating though.

Thanks for all the help!

Cheers

Stuart
   

[Galmpton_Miller]

Wow, sorry for the huge photos!

[elagache]

Dear Stuart and WeatherCat station caregivers,

Thanks for taking the time to share with us your troubleshooting efforts.  Sorry, that in the end you discovered that you would have to replace the anemometer anyway.  Thank's to your troubleshooting, it will be easier for someone else with this sort of problem to decide what to do.

Wow, sorry for the huge photos!

Don't worry about it unless you would like to have something neater in the future.  Some photo upload services have special services so that you can provide a reasonable sized "thumbnail" to be displayed on the forum but still provide access to the full-resolution images if someone needs all that detail.  Thanks to a recommendation from another WeatherCat user, I've been using SmugMug and like it although it is a paid service.

https://www.smugmug.com/

If you want to see how this allows you format images, you can look at this thread where I have posted some pictures:

http://athena.trixology.com/index.php?topic=1842.0

My understanding is that free photo upload services have started to provide similar capabilities, perhaps another WeatherCat user can offer a suggestion.

Best of luck getting your weather station back up to full data collection!

Cheers, Edouard

[Galmpton_Miller]

Thanks Edouard
I have ordered the anemometer from Germany and will let you know the results.

Thanks, too, for the information on posting photos.

Cheers

Stuart

[Galmpton_Miller]

Hi group
Replacement anemometer installed and everything is working as it should!
I plan to take the old one apart and see if I can figure out what happened to the wind speed reed switch.

Thanks again for all the help.

Cheers

Stuart

[elagache]

Dear Stuart and WeatherCat station troubleshooters,

Replacement anemometer installed and everything is working as it should!

Congratulations on getting your station back up to normal data collection! 

I plan to take the old one apart and see if I can figure out what happened to the wind speed reed switch.

Let us know if you figure out any clever maintenance tricks as a result.  We all need to be prepared to repair our stations since the instruments will not last forever. 

Cheers, Edouard

[Galmpton_Miller]

Will do Edouard

[Will Woodgate]

Thanks for the various tips, photos and links.

Unfortunately my VP2 anemometer (or another component in the station) appears to have broken on 5th November. Wind direction is working perfectly fine but the anemometer is stuck on 0 MPH on the wireless console and in WeatherCat. There are no sensor errors showing in WeatherCat.

Also of note, the ISS is on its second new battery in 3 weeks! So as @elagache suggested, I think something might be shorting-out somewhere.

I contacted Davis last week and they told me the 0 MPH wind recordings is most likely the a faulty reed switch on the anemometer, but they don't have a wind test cable available for UK customers. So it was advised that I contact the original dealer for technical support, which I did.

The store I bought the VP2 from in early 2009 has changed ownership and they no longer carry any VP2 spares in stock. A replacement anemometer is something they'd have to order. They are going to prepare a quote for me but said it would be in the region of ?200 or more.

It was pointed out to me that for ?75 more I can have a brand new LaCrosse or Oregon WMR 200 which would probably be suffice for my needs! There are now a lot more prosumer weather stations on the market nowadays that are WeatherCat compatible. This Davis one is now close to 6 years old and I fear the bill for new parts could rapidly ramp up.

If the weather is better tomorrow I'll probably take the anemometer off its pole for a thorough inspection and clean. I did notice a little bit of condensation inside the ISS, so again I'll leave the cover off that for a few hours if we have some sunshine.

[HantaYo]

It was pointed out to me that for ?75 more I can have a brand new LaCrosse or Oregon WMR 200 which would probably be suffice for my needs! There are now a lot more prosumer weather stations on the market nowadays that are WeatherCat compatible. This Davis one is now close to 6 years old and I fear the bill for new parts could rapidly ramp up.

If my Davis VP needed replaced I likely would go with another brand.  The Davis VP 2 is outdated and in need of a model update.