Wind Chill and Dew Point

[ambientweather]

I have a customer that ordered the WS-1080 (WH-1081 by Fine Offset).

1. He is stating that at 34 degF and a wind speed of 40 degF, his wind chill was also 34 degF. It may be a firmware issue. Anyone seen anything like this?

2. His Dew Point was reading (-|18.1), or a "sideways T with 18.1", not a negative sign.

Anyone heard of issues with the wind chill and dew point calculation? This is on the console and not in the software.

Regards,

Ed

[scottjge]

Hi all,

I am the customer that Ed was talking about. The unit that I have has worked flawlessly for about 2 weeks then I started to erratic data on the console. I have reset the console twice hoping that it would clear things up but the dew point still has the
-|, (sideways T) before the Dew point reading. For an example tonight the dew point reads -|21.2 F. Personally I think it is in the console itself, the time span is just about right for a electronic failure. I worked in electronics for 25 years and I hvae been programming Microprocessor for test equipment for about 5 years and when they tell you that there is approx. a 10% failure rate, believe it. I have seen it many times. For the wind chill... it just quit working and just tracks with the temperature reading.....again I believe this is a failure of the Microprocessor also. What ever algorithm they are using for the computation has failed or stuck in a loop. I don't think it is in the sensor because everything seems to be reporting and seems to be fairly accurate. The rain amounts are in the console, I think, because I have sit here and watch and update of the data and the total rainfall will read 2.20 inches, then the next data update the total rainfall would change to 2,560.36 inches. Waited for the next update, the total rainfall went back to 2.20 inches. It has stayed there with no change for a while but then again I haven't been sitting here watching the console every second. I have even disconnected all the sensors, reset the console, and the dew point would read -|0.00. The sideways T is still there even though it is not receiving data. So what does that tell ya ?

Whether it does any good or not, I emailed Fine Instruments tonight explaining the problems and explaining why I think the way that I think. I also explained what everyone else has experienced on this board and other forums that I have run across looking for information. I doubt if I even get a reply but time will tell. I found out years ago that a company will listen to a squeaky wheel if it get loud enough, so let's wait and see what happens.

I must commit on the Cumulus software. I like it, easy to use, easy to read and decipher, and easy to set up. Works out of the box with no snags. Very nice job, you must be commended. Much better than EasyWeather.

There I have vented and told my thoughts. Thank you for listening

Scotty

[daj]

Hi Scotty (and Ed)

This forum is obviously predominately geared towards Cumulus support and its operation, but we do all have a variety of kit connected to Cumulus and have various skill levels on the hardware side. For the record, I have no hardware skill other than being the owner of a FineOffset.

I think it is fair to say, and I only base this on my readings on this forum, that the FineOffset/Watson kit is not always constructed to the highest standard and I read several comments of poor soldering, etc

If you have had the device only a matter of weeks then I see no reason why it can not be replaced under warranty as it is clearly failing.

[Charlie]

Yes, my money would be on a bad solder joint (or two!). If it was out of warranty, I'd say open it and have a look, but given it's age you should ask for warranty replacement.

You might as well spend your spare time with your hobby, rather than troubleshooting a defect for the manufacturer.

[scottjge]

Thank you to all for you input and advise.

I could ask for a exchange and Ed has already offered a refund of my money if I was not happy with the unit. the truth is I am happy with the unit.( when it works) It has worked great since I have had it and I am watching it to see what it is doing to see if I can figure how to fix it. My thoughts is..... if I exchange the unit, I may end up with just another unit that has some other issue besides of what I have now, especially after reading some of the post that others are having.

I thought that I would give a little update so everyone could see what it going on. This example only solidifies my theory that it is just something wrong with the dew point and wind chill calculations.
Here are some examples of the tracking of two different weather stations.

---------------- Davis Vantage Pro -------------------------------------------- WH1081PC

Outside Temp ------------42.1 F --------------------------------------------------------42.6 F
Dew Point ------------38.3 F --------------------------------------------------------37.6 F
Humidity ------------88% ---------------------------------------------------------- 87.6%
wind Speed ----------- 1.0 MPH --------------------- --------------------------------- 1.6 MPH
wind Gust ----------- 3.0 MPH ------------------------------------------------------- 3.1 MPH
Wind Direction ---------- WNW --------------------------------------------------------- WNW
Barometric Pressure --- 30.17 in ------------------------------------------------------- 30.17 in
Rain Fall ---------- .01 in ------------------------------------------------------------- .01 in
Software WX Solutions 1.8.5.3 ------------------------------------------- Cumulus 1.89

These two stations are a few mile apart but are basically set up the same. I think the readings are very acceptable for the WH1081PC considering the price of the unit. So again I still think that it is a problem with the console and has something to due with calculations because both wind chill and dew point are just a calculation of what two sensors are reporting. Right now there is no wind chill factor with the present temperature, the due point has changed due to conditions hence there is no sideways T ( -| ) in the reading of the display. Also...... which I forgot to include in my initial post was that when the unit does give erroneous readings, the software (Cumulus) does not include the same erroneous reading. As far as I can tell, Cumulus has always displayed the correct readings, it is just the console that has the funny readings. The only way that I will be able to tell if my theory is correct, is to wait until the temperature drops again to see if the erroneous readings appear again. If I had the extra money, I would buy another console and compare the two side by side with the same sensors and setup to see if it was just my unit or if it happens on both units. Unfortunately I don't have the money to play with right now. I am having severe financial problems due to health and living. That is why I ended up with a Fine/Offset instead of a Davis.

Okay, there is my update for today. It is suppose to get down into the 20's within the next couple of days so I can't wait to see if the erroneous readings come back when the unit has to do some more wind chill and dew point calculations.

Thanks for listening to me blab on about my problems.

Scotty

Cumulus Rocks !

[beteljuice]

.. the due point has changed due to conditions hence there is no sideways T ( -| ) in the reading of the display...

You earlier said that -| was being displayed even at 0 (zero degrees) what has changed ?
That problem looks like it may be a display panel failure (or its driver), ie. 3 segments being lit when your dew point is - negative rather than 1 segment.

Windchill, the original quote from AW doesn't make sense (Windspeed as a temperature). Are you having any wind to 'kick in' the windchill factor ?

[scottjge]

At the time I had winds of 40 mph and a temperature of 34 degrees F. and the wind chill was 34 degrees F.

The dew point has changed for 18.1 degrees to 37.4 degrees hence I will have to wait for it to go back down to see if the erroneous readings comes back.

Scotty

[scottjge]

Here is an update on the dew point problems that I have been having. I sit here and watched it over a period of time and the due point is constantly changing. The console and Cumulus are changing together but in a non-linear fashion.
Here are just a few of my recordings.

[b]Console---------------------------------Cumulus[/b]---------------------------Difference

25.2 ---------------------------------------------22.8---------------------------------2.4
25.3 ---------------------------------------------23.1--------------------------------- 2.2
25.2 ---------------------------------------------22.8--------------------------------- 2.4
26.1 ---------------------------------------------23.8 ---------------------------------2.3
24.6 -------------------------------------------- 22.0 --------------------------------- 2.4
-|18.5 ------------------------------------------ 25.0 ----------------------------------6.5
21.7 --------------------------------------------18.5 ----------------------------------3.2
23.4 -------------------------------------------- 20.6 ---------------------------------2.8

Wouldn't you think that the software and console track exactly the same amount with each change ? Second, if you notice, the sideways T comeback when it got to 18.5. It seams that sideways T comes and goes at will. I see it at a reading of 23.6 earlier but now it only happens when it is below 20. What gives ? Any ideas ?

Any help or advise would be greatly appreciated.

Scotty

[steve]

Wouldn't you think that the software and console track exactly the same amount with each change ?

Cumulus has to calculate the dew point itself (from the temperature and humidity) because the console doesn't supply it via the PC interface, so you might expect some slight differences in the values each one shows. But it seems fairly clear that your station is faulty.

[scottjge]

Thanks for your input Steve, it is greatly appreciated. What part of the station do you feel is faulty ? If I can pin in down for sure I would take to Ed to see if he would replace the faulty part. Would it be the console, or the sensors ? I hate to send the wrong diagnosis to Ed. Everything seem to track the Davis except for the dew point and humidity.

thanks,
Scotty

[daj]

Scotty

Surely Ed should simply have this replaced under the manufactures guarantee and not try to repair (and therefore invalidate your warranty)

I certainly would not accept a repair for a device that is only a few weeks old

[steve]

Would it be the console, or the sensors ? I hate to send the wrong diagnosis to Ed. Everything seem to track the Davis except for the dew point and humidity.

The odd 'sideways T' symbol suggests to me that the display is faulty (as I think someone else suggested). If Cumulus is showing figures that seem reasonable, that would seem to confirm that theory. But to be honest I am no hardware/electronics expert, so it's hard for me to say.

[Gina]

The odd 'sideways T' symbol suggests to me that the display is faulty (as I think someone else suggested). If Cumulus is showing figures that seem reasonable, that would seem to confirm that theory. But to be honest I am no hardware/electronics expert, so it's hard for me to say.

I agree, the sideways T is not a standard readout, is it? As I see it, this would point to a fault in the microprocessor that drives the display, the display itself, or it could be in the plastic looking conductor that connects the circuit board to the display. If there isn't perfect contact you could well lose segments. However, if the whole display section is displaced to the right with the sideways T added at the left then this points to the microprocessor or it's program.

In any event, it has to be a fault in the console.

[scottjge]

I will contact Steve and see what he says about replacement. I just hate to bother the guy until I am sure which item is defective. Secondly, I hate to climb that tower to take everything down if I don't have to. But personally, I do believe it is the display, which is the easiest to change out.

Thanks to all for your opinions, I really appreciate the input and suggestions.

Scotty

[ambientweather]

We are definitely replace the console. It does sound like a bad segment and not a firmare issue.

Regards,

Ed