Alternate setup/device for rain sensing?

I have my Tempest mounted up on a mast on my roof, which is generally the best/only good place for most of the readings. It’s a pretty solid setup - the mast is mounted using a fairly robust 5’ tall mini-tower. The mast itself is made of a much thicker steel than typically used on masts and everything is pretty secure. However when the winds get up around 30mph the rain sensor goes nuts. It recorded over 30" of rain on a sunny day.

For a variety of reasons, filling the mast with sand is not really an option. So I don’t really have any bright ideas on how to improve things. And since I often get 30+mph winds during the winter months here, something needs to be done if I want to be able to record rain. For now I’ve disabled reporting of rain to wunderground, and I’ve disabled it from my CWOP/APRS reports. But it would be nice to get it back.

If anyone has thoughts about solutions I might not have thought about, please feel free to chime in.

About the only option I’ve been able to come up with is to buy a 2nd Tempest and mount it somewhere else, protected from the wind. This brings up a couple questions:

  1. Is another Tempest the “best” option? I was thinking of using a Tempest so that I could have a backup of sorts to main my Tempest. But would one of the other WeatherFlow devices be a better option?

  2. My assumption is that I can use a single hub for both Tempests (I believe my 2nd location should have a decent enough signal to the hub I’m currently using for my Tempest). Is this correct?

  3. Is there a way to configure the hub so that it takes “everything but the rain” from my main Tempest and then takes only the rain from my 2nd Tempest? I can easily do that for my CWOP/APRS reports because I can just set up the sensor map in weewx to pull from the device I want for each reading. But I’m not sure if/how I can do that for other things, especially like the automatic reports to wunderground. Or the reports on tempestwx.com.

Any other options or things I might consider?

You have a few pictures to share ?

  1. 1 hub can take several devices without any problem
  2. you can do the same via weewx for WU

Regarding weewx and WU - that’s true, I could just have weewx update WU instead of letting WeatherFlow do it for me.

For pictures, I don’t have any great pictures, and it’s raining right now. But here’s one I took a little while ago. And yes, it is a little “busy”, and it’s possible some of the things on there are causing/contributing vibrations. But I can’t take anything off there.

I have a feeling that discone antenna vibrates plenty in high winds to cause the station to read inaccurate. If you have another rain gauge station, try submitting rain data or info to this link so that they can try calibration settings remotely.

It’s not a discone, though it is an antenna. Discones do have a lot of vibrations. It does sway, but doesn’t really vibrate much, at least best I can tell by putting my hand on it during heavy winds. That being said, it’s certainly possible that it’s a contributor, but there’s really nothing I can do about it - that antenna needs to be there.

indeed, there is a lot to make the whole thing vibrate. Remember it’s the micro vibrations that are causing problems (maybe even the wires cause it). And since it is all steel, it conducts perfectly those vibrations.
What you could try is to use some damping material between the tube and the Tempest. Some kinda silicon like tape ? I think @iladyman is expert in building the most weird dampers :slight_smile:

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if you are going to buy something just for rain, don’t buy a second tempest. Many have reported it lacks accuracy when it comes to total accumulated rain, but they are pretty good for reporting the start of rain. At some point they might come up with a bucket based detector that communicates with the hub, but if you want accurate rain now, buy a detector from a different brand.
But first I suggest mounting your current one using some dampening system. Also make sure none of the wires in your setup are starting to rattle at high wind speeds.

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Indeed, don’t buy another Tempest for rain, the haptic sensor just cannot be trusted. Also, I don’t think it make any sense to ask Weatherflow to calibrate your station with external data as long as the vibrations are not fixed.

Weatherflow should just develop a conventional rain gauge that connects to the hub and replace the haptic sensor of the Tempest (and give it for free or with a big discount to existing users).

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We’ve been nagging for a wireless tipping bucket for a long time now. Integration with the haptic sensor would give accurate start and end times and the bucket accurate precipitation amounts.

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Thanks to everyone that’s provided feedback so far. I probably should’ve elaborated a little more on my own thoughts/assessments. I’m kind of an “audio guy” - while more of my focus is on the digital processing of audio, audio in general is a bit of a hobby/passion. And with various installations of antennas and other things I’m at least somewhat aware of the things that cause vibrations. But I definitely underestimated the scope of the problem initially. After the rain sensor was getting set off continuously while the neighbor was hammering nails into plywood, the scope started to come into greater relief. That was the point at which I mostly gave up on any notion of being able to address the problems with the mast mount, and started looking at ways to hide a sensor in the most protected place possible, mounted to something like a 4x4 post. Given that 40+mph winds are pretty common right here during the winter, and how sensitive the sensor seems to be, I’m just having a hard time seeing any way to fix the problem.

FWIW, my assessment, based on looking at the things on my mast, and feeling different parts while the wind was blowing, these are the most likely vibration creators in rough order of likelihood:

  1. The guy wires (which are rope, not wire)
  2. The tail ends of the pipe clamps which are mounting the 3 cameras to the mast
  3. The general turbulence caused by the variety of irregular surfaces
  4. The ground radials for the antenna

I have some sound insulating material which I had been pondering putting at the attachment between the side-arm mount for the Tempest and the mast, but I just wasn’t sure how much effort it was worth putting in compared to the seeming futility of the effort. That being said, I could swear I saw a mount on a sailboat mast, which I would think would be much more troublesome, so maybe if that’s possible, there’s at least some hope. I dunno, maybe I’ll give it a try this weekend.

I suggest you mount it on a pole as far away from other structures as possible. These devices work best when they are segregated from other objects.

Mine is on a 16 foot fiberglass pole set all alone and I only get false rain the the 60 to 80 mph winds kick up dust and sand.

Unfortunately that’s not really an option. I don’t have a large property - the only location which has no wind obstructions is the roof. Due to the design of the roof, there’s only a 10’x10’ area where I can install it, and any location that isn’t on the mast where it currently is would take it out of the RF “null” of the antenna, which has impacts on the Tempest’s sensors when the radio transmits.

My tests with a sky indicated false rain when on a metal pole inside the house I tapped the pole repeatedly with a plastic pen. I see wires that might move against the pole in strong winds and would add those to your list of possible source of vibrations.

And another possible source I suspect is the bayonet fitting between the mount and the Tempest. I put silicone tape around that connection trying to prevent any movement.

I do have a dual Sky setup with one in the garden for comparing rainfall to the Sky on the very vibrating pole along with a Tempest and compare them to two funnel gauges. The Sky in the garden does not suffer the vibration issue and is usually close but can be way off at times. The Tempest on the vibrating pole is better than the Sky for the vibration issue.
During hot dry windy weather when a rain shower passes that wets everything and would make you feel wet if you were outside and cause dust to stick to the water on your windows the funnel gauges can be dry at the bottom due to evaporation preventing the water from running to the bottom. In this type of rain a tipping bucket would also dry before tipping the bucket. But my Sky or Tempest can record that as rain.
For my rain records I use my two funnel gauges which can vary 10% difference depending on wind directions.

For the challenge I did build a vibration resistant mount that worked up to 50mph but the rubber I use perished after about 12 months. If I was building that again I would paint the rubber. I dont need accurate rain, I was just building it for the challenge.

This thread discusses my experiments and design with lots of flappy vibration and no false rain up to 40 knots or 50mph. But the Tempest cushioning and the firmware has been improved since then:

A tipping bucket requires maintenance so I dont bother using the couple I have lying around with my spare parts. My plastic funnel gauges work well enough for me.
good luck cheers Ian :slight_smile: