Peet Bros with Davis wind vane

[Chris Thompstone]

Hi Guys, anyone know if you can use a davis wind vane on a ultimeter 2100?

My wind vane has broken again, this one didn't last long (about 6 months, 1 year maybe)

It's difficult and expensive to get these in the UK, have to import etc.

So would like to try something else instead.

[D R]

From my knowledge, the answer is no.

The Davis uses pulses to signal wind speed, and the Peet Bros does, too.

The major difference is that the Davis uses the much more traditional potentiometer to deliver a voltage and the ISS reads that to convert to a wind direction.

The Peet Brothers does something much more difficult and very different.  It times when one of the magnets makes or breaks and then depending upon the time until it pulses again, determines the angle of rotation through which the wind speed magnet has rotated, simplified explanation.  Therefore, if there is  no rotation of the wind speed magnet, there cannot be a determination of which direction the vane is pointing, unlike a no-wind condition for a Davis, which of course will give a voltage on the wind direction sense line.

Very odd, but seems to work for them.   If you go to Davis's web site, there is a better explanation of how they designed their unit.  It certainly gets rid of the potentiometer and it wearing out, but the timing circuitry to measure the angle has to be a bit more complicated.

Dale

[Chris Thompstone]

Well thanks for the info

I did wonder that it's probably be different.

Thanks again

Not sure where that leaves me

[D R]

In those situations where a conversion can be done, rather than a direct drop in replacement, it usually takes some electronic magic.  Davis made a unit to take an NRS or RM Young wind monitor and simulate it being a Davis weather sensor package.

A gentleman in Florida did a whole bunch of programing to make a Davis head look like a Heathkit ID-4001 or 5001, but he did that for a living.

This is going to be tough since I don't know if anyone is privy to the actual workings of how the Peet Bros figures out the angle from the pulses.   I can see the concept but have no idea how to emulate it.

[Tom Keffer]

Hang on. Maybe I don't understand the situation, but you said you wanted to replace the "wind vane." Do you mean just the plastic arrow-like piece? Or, the whole thing, including the potentiometer?

If it's just the arrow, I don't see why you can't use most anything that would fit. It just has to point into the wind. Or, 3D print something. Or, epoxy the old one back together.

-tk

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[D R]

Indeed, I may have jumped to a wrong conclusion, also.


I should have clarified.  My response was based on getting a whole
sensor unit, windspeed and wind direction, replaced.


If it is just a mechanical problem (broken  nose or fin) on the Peet
wind direction unit, then as Tom suggests a bit of work with epoxy and
re-inforcement mesh works wonders.


I have just finished fixing the nose of my Peet unit that arrived with
the nosepiece broken off and a little of the screw pointing through. 
Very easy to do.


I have made numerous repairs to the wind direction vane on the Texas
Weather Instruments sender because it is notoriously weak where the bolt
attaches the vane to the encoder.


Please indicate what you are wanting to replace:  The whole unit with a
Davis, or just the VANE that turns the cap with the magnet inside of it.


Dale


 (very sorry if I gave wrong advice)

[Chris Thompstone]

sorry for the slow response, got dealing with other stuff.

The Peet Bros wind vane, looks fine from the ground.  However the wind direction is normally wrong.  But sometimes right (often when very windy), but then wrong later again etc etc.

The wind speed seems OK...  Although it does sound a bit rattlely.

So the peet bros wind vane is difficult to get in the UK and it hasn't been up for very long before it starting playing up.

So thought maybe I could change to a davis one and use that with the peet bros kit, however that sounds like it wont work.

Chris