Topic: Vantage Vue - both wind speed and direction drop to zero together intermittently

[beachiceleaf]

Hi, looking for some help (also contacting the Weather Shop where I bought from). We’ve had a Davis Vantage Vue running for a few weeks. We are seeing intermittent zero wind speed and direction readings, even with the cups spinning very quickly. On the app and the console the wind average shows mostly as zero, but with high gust values showing more realistic higher values.

I captured a UDP real time broadcast every 2.5s for 20 mins during Storm Christoph, when it was spinning consistently very quickly. Strangely the values for wind_speed_last and both drop to zero at the same time and intermittently. (See images with details)

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On the whole the readings are much lower than I’d expect. Obviously I’m NOT expecting to match the weather forecast, but certainly more than a couple of km/h. Especially during Christoph(!).

I’ve checked the screw which attaches the wind cups to the anemometer. It is tight and if you pull up gently on them (per the manual instructions) they don’t come off. And they are spinning freely.

Hoping we've not got faulty equipment! Couldn’t see anything else similar on here (apologies if I’ve missed something). Thanks in advance for any thoughts.

[johnd]

Obvious question is what wireless reception is like - my immediate thought is that the signal is very weak and so reception is intermittent. If you've got a console too then look at the 2nd wireless diagnostic screen and monitor the RSSI value over a period of time. (Or look at the Health tab on weatherlink.com.)

Low wind speed readings are very likely because the Vue ISS is too low or otherwise sheltered.

[beachiceleaf]

Thanks for your response - appreciated! Looking at the signal now, it looks pretty good, both on strength and number of packets received. But I will keep an eye on it.

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Regarding positioning, I'm resigned to the fact that we don't have a perfect exposed spot for it so won't be getting true readings for speed. But Storm Christoph certainly highlighted that the speed it spins at "visually" isn't corresponding to the speed readings we are getting. And then of course the drop outs in wind direction are a bit suspicious.

[johnd]

Looks like a good strong signal so that ticks one box.

It's very rare for a Vue ISS to be faulty out of the box, but obviously not impossible. But I'd still be looking first to rule out other possible explanations. eg I don't whether or not you're in an isolated location, but occasionally you can get this sort of effect if there's another nearby Davis wireless station that could be interfering with your signal. Might be worth changing the wireless channel to eg #2 or #3 (on both ISS and console/WLL of course) and seeing whether this makes any difference.

[jackman]

With 100% reception is does rule out a signal strength issue. I'd suspect the ISS and give Davis a call.

[PacoJavi]

I thought I could put my 2 cents in this, since I had a Davis Vue installed in Cork, Ireland for 2 years before decommissioning it:

My ISS was installed close to the house roof, sheltered from the main westerly/southwesterly winds that batter the country, specially during winter.
The height difference between the top of the roof and the ISS was approximately 1 m.

During these 2 years, the max. Speed Gust that I recorded was 32 km/h and I can assure you that during this time, there were gusts of > 100km/h measured in the open more than once.
The siting is absolutely critical specially on those countries where the wind blows manly from 1 or 2 directions, otherwise rain totals and wind max. Gusts will get affected severely (There even was a day when I recorded 0.6 mm in total, while the stations in the surroundings varied between 20 and 30 mm. Guess where the wind was blowing from that day  )

I have also experienced the zero values for both wind speed and direction in my VP2: when the wind cups do not spin, the wind direction either shows automatically 0 degrees, or nothing at all.

If I were you, a would site the ISS in the open for a few hours on a windy day and see if you still get those zero values before contacting support.

I hope this helps.

[beachiceleaf]

I had a chance to change the channel from the default of 1 yesterday. That made no difference, but glad to have ruled it out!

I also took a handheld anemometer up to the site of the weather station to do a rough comparison. I was seeing readings of 8-15km/h on the handheld and in the same period the highest gust shown by the WLL data was 7km/h. And the average wind speed was shown as 0km/h. So it is really starting to feel like a hardware issue. I did also remove and replace the wind cups to ensure they were seated properly...

Still waiting for Weather Shop to come back to my request for support.

[beachiceleaf]

Well it took about 2 months in total to deal with support at the Weather Shop (1 month with email replies taking a week each time and then 1 month to return / replace the ISS) but I'm delighted to say that it obviously was faulty and the new one works like a dream. Suddenly the wind speeds actually make sense.

Just wanted to share in case someone runs across the same problems and find this post. Thanks again to everyone who replied and helped here!