Topic: Retrieving data locally.

[gdicarlo]

I am considering purchasing a Davis VP2. Is it possible to store the data on a data logger and download it to your computer about once a week, without going online and having to upload it to weatherlink?

[johnd]

I am considering purchasing a Davis VP2. Is it possible to store the data on a data logger and download it to your computer about once a week, without going online and having to upload it to weatherlink?

Yes. (Assuming you're talking about a VP2-compatible logger like the Davis Weatherlink USB logger or the WiFi Logger as a couple of examples.) The API uses binary data so you need to be comfortable with that, but it's all well-documented. There are of course several programs that will do this for you, but it sounds like you want to write your own software.

[gdicarlo]

I don't wish to write my own software. I just don't want to pay the subscription fee to weatherlink to download my own historical data. I just want to store and view it on my own computer without going online.

[BigOkie]

There are other solutions.  If you're familiar with Raspberry Pi that can be a (low power) always-on solution, but can also serve to download data periodically instead.  Cumulus MX can afford you the ability to store the data in a database, but even without the database Cumulus MX will store it in monthly named data files.  Perhaps this could serve your purpose?  This solution can be a little time consuming to get started initially but is incredibly reliable and largely maintenance free once it is set up.

Also, it's free (well, the Raspberry PI isn't, but...).  CumulusMX can also be run on a regular Windows machine.

[gdicarlo]

I'm not familiar with raspberry pi. The Cumulous solution sounds good. Which is a better logger to use, the wifi or the usb?

[Storm017]

You could also use WeeWx to interface with the VP2. With WeeWx, you can view and store data locally; upload data to various sites . If planning to use a RPI, ensure to use a good micro SD card and power supply. I'm using a RPI 3B+ with the WeatherLink  USB Data Logger.

[ocala]

I'm not familiar with raspberry pi. The Cumulous solution sounds good. Which is a better logger to use, the wifi or the usb?

I do exactly what you describe once a week. Download to the weatherlink software and to Cumulus. I would go with the wifi logger myself. It's what I use. The wifi logger will upload your data to several sites so you can access it during the week but don't have to run your PC 24/7.
I should add that  both the usb and wifi logger have storage limits based on your archive interval. They are as follows.
1 minute-42 hours.
5 minute-8 days
10 minute-17 days
15 minute-26 days
30 minute-53 days
60 minte-106 days
120 minute-213 days.

[Mattk]

This hasn't got to be complicated. Simply download and install Davis's free WeatherPC which can be found on WeatherLink.com and you will achieve what you require.

WeatherLinkIP logger would be the suggestion but since Davis has discontinued these (for their own benefit) you may be hard pressed to still find one otherwise my second choice would be a serial version. There are other options but this keeps things straight forward and simple

[gdicarlo]

I am looking to store my archive data in 5 minute intervals. I would download the data a couple times a week. I would like to store that data in csv files, so that I can view the data in excel.  Can I do this this without using weatherlink? I was thinking using wifilogger2 and Cumulous.

[PaulMy]

Hi,
Yes you can use CumulusMX without using Weatherlink.  CumulusMX saves the monthly log in MmmYYlog.txt format which can be read/opened by most programs including Excel, and at whatever logging increment you set, i.e. 1 min, or 5, 10, 15, 30 minutes.  Be careful, don't reverse save from Excel to .txt as then the files may not be valid in CumulusMX.  5 minute interval gives about 17 days before the logger overwrites so twice a week is well within a 5 min interval and your twice a week download.


You set the logging interval for CumulusMX data files in CumulusMX and that interval should be the same as the Console/logger is set.  Otherwise Cumulus won't know where to start in doing the archive catch up and therefore will download the full logger each time you start CumulusMX.  Console/logger interval is set in Weatherlink.


Enjoy,
Paul

[Asbee]

Hey!

This is my first post here and i dont mean to hijack this thread, but when this thread seems to handle same thing that i wanna achieve i thought it would be probably fine to post my problem here.

So i have Vantage pro2 and i got davis instruments serial data logger that is connected to my raspberry pi serial port.
I want to use my raspberry pi to read weather data from the logger and send it to my server which uses influxdb.
Im having hard time finding any help how to do this. It seems that i always need to use weatherlink app to get my data, but i dont wanna do that.

I've tried to read data using python pyserial, but i dont seem to get anything out.
Im very new with raspberry pi and python so im having hard time figuring this out.
So if anyone could direct me to right direction i would be very happy.

[vreihen]

WeeWX is the answer.  What was the question?????

[Asbee]

WeeWX is the answer.  What was the question?????

My question is how i can read data from the data logger using python?
And i wanna send my data to my server which uses InfluxDB.
How do i achieve this?

Is WeeWX the perfect tool for this?
What i read from the WeeWX site it says it only supports sqlite and MYsql.
So i dont know if it is the right program for me.

[Storm017]

There are drivers for influx: https://github.com/matthewwall/weewx-influx

[vinceskahan]

Is WeeWX the perfect tool for this?
What i read from the WeeWX site it says it only supports sqlite and MYsql.
So i dont know if it is the right program for me.

You need to understand what a 'driver' is versus what an 'extension' is.

A driver can feed either of the two databases weewx supports natively.  Just go with sqlite3 for simplicity.

An extension 'extends' the functionality to do other things.  The weewx-influx extension would 'also' feed a influxdb server.

Another way is to run weewx with the MQTT extension to feed a MQTT broker, and have telegraf subscribe to that and feed your influxdb....but just going weewx->influxdb in one step is cleaner.

(I use the MQTT path because I use Home Assistant for a display and have that pi3 also subscribe to the MQTT feed).

[johnd]

My question is how i can read data from the data logger using python?

The API for retrieving  data from a serial logger is described in the first section of the Davis Serial Tech Ref document (see Davis Support website for a download). You'll need to work out how to implement the API commands and responses in Python, but many developers and users have done this over the years, including I'm sure with Python, so it's relatively straightforward for anyone with basic programming skills. Indeed there seem to be some libraries available to do this like at https://pypi.org/project/PyVantagePro/ .

Getting the data into Influxdb is obviously another step, but again there seem to be Python libraries for Influxdb, so it shouldn't be too difficult.

[cmelby76]

Hi,

So I have a WeatherLink IP windows software with data logger for sale along my vantage Vue. But, I am willing to sell the weatherlinkIP separately if you are interested in it?  Let me know