Davis Weather Wizard III Serial Port Connection


I recently acquired a used Davis Instrument Weather Wizard III which I would like to connect to my HomeSeer server via a serial port . I noticed it had a "Weather Link" connection on the back, but investigating further, it seems that I need a Weather Link kit which includes a "data logger" hardware and can not connect the serial port "directly" to that input connection.

Does anyone know if this is true? I sure would like to just connect the console directly and not have to purchase another piece of hardware. Also, if I can do this, does anyone know the pinout to a DB-9 connection? I looked at Davis Instrument's site with no luck.


Unfortunately this is true. I've been "shopping" for a Davis station for almost a month now on EBay but the cost of the station and the add-on data logger is nearly cost prohibitive to me for an armature weather station. My one-wire system and PC was taken out by lightning about a month ago and man do I miss it.
e and Rupp;

Thanks for the replies. This is a bummer as the cost of the data logger/serial connection is almost the same as the cost of the unit itself. :) Also, the unit I acquired needs the AC adapter as well.

I will have to rethink this as all I really wanted ultimately was wind measurement so I can add this parameter to my sprinkler system controls.

I think I'll have to add all this up and see what is a better solution for the money as this does make the one wire system more attractive, plus I will have the opportunity for expansion to other one-wire type measurements.
You are in the same boat as I'm in. Do I rebuild my one-wire weather system or buy a Davis Wireless system. My one-wire system has been zapped by lightning so many times I want to try a wireless system or so I thought.
If you can afford it you won't regret getting a Davis. I have had the wireless vantage pro 2 for about 2 years now and just love it. I have it feed my home web site using the weatherlink software and data logger from http://www.ambientweather.com/ and now I also use one of the free plugins to pull the weather data into homeseer.

The only thing I don't like about using the data logger is that the pc running the weather software to pull the data from the data logger has to be connected via usb so this means you are limited in the distance between where your data logger is located and your pc. I am using a 16 foot usb cable to run from my weather display down to the basement where my webserver and homeseer software are running.
Just for grins I priced out a one-wire solution that would duplicate the measurements from the Davis Instruments Weather Wizard III. It's listed in the screen shot below. Total cost is around $265 plus shipping.

I don't think I'm missing anything and this will give me direct access to a serial port interface, plus be able to expand (in a 'star' topology) to other sensors in the future.

Of course, just thinking about this all right now! :)

The only thing I don't like with the one-wire is the accuracy of the temperature sensors. I'm not sure what the accuracy of the Davis Instruments device is (will look this up later).


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BSR, I have the 1 wire solution. I find the temperature accuracy to be great! What have heard to the contrary?
According to what I could find online about the Weather Wizard III it has the same stated accuracy of +/-1F (+/-0.5C) as the DS18S20 1-Wire temperature sensor.

Don't get me wrong, I'm not saying the one-wire is bad (I think I've proven it's a pretty good economical choice in my above comparison), I would just like temperature accuracies in the +/- 0.5 F range. ;)

Maybe I'm being too picky about temp accuracies. Is there anyone using a DS18S20 sensor related temperature measurement to control thermostats for room control? Do they find this accuracy adequate?
I've used a One-Wire weather station for years but it does get expensive replacing the entire setup each time we get a close lightning strike. I'm not sure how much lightning you guys get but in early March a strike near the house (a couple of hundred of yards) took out my DS9097U and rain gauge counter board. Then just 2 weeks ago another close strike took out the rest and the PC. I lost 4 temp sensors, 2 humidity sensors, a barometer, wind (direction and speed), and my PC. So I'm bidding on the Davis Wireless systems now. It was much cheaper at first but over the last 10 years I've gone through a ton of sensors. Just a thought you may want to consider.
The DS18B20 has 12 bits of resolution (0.125 C) vs. the DS18S20 at 9 bits (0.5 C). I'm not certain if the accuracy is any different between the two. For absolute temperature measurent 0.5 degrees is OK, but if you are calculating rates based upon temperture change to use for anticipation or PD control then even 12 bits is marginal.

I heard a lot about weather stations from those on the floor at EHX last month. Typically the attendees were the professionals and Davis generally did not measure up to their expectations due to various failures. I suspect at a consumer rather than professional show the Davis would get good reviews and things like $99 LaCrosse with a PC interface would be beaten down. The no-moving-parts, solar powered, radio link unit from Campbell at $5K is a nice commercial quality unit and sleek enough that homeowner associations would not object. In the comsumer market there is a Honeywell-branded unit that also contains a UV sensor in the mid-$200 range. Reviews have not been bad, but it also has not been around too long. UV or Solar Radiation are important sensors if the objective for the weather station is ET-based irrigation. These do not come with the base Davis Vantage Pro.