Advanced Weatherlink Data Loggers
In addition to the standard 6510USB and 6510SER Weatherlink data loggers (with USB and Serial/RS232 interfaces respectively) there are a set of five further Weatherlink data logger models available. These additional loggers can be regarded as special-purpose or advanced in that they offer all the features of the standard serial and USB loggers, but also provide further special features that will be relevant to particular applications. All Weatherlink data loggers in the 65xx family can be used with any recent Davis weather station model, which includes both original Vantage Pro and the current Vantage Pro 2 models, together with the new Vantage Vue stations.
These advanced or special-purpose loggers fall into two groups:
- The 6555 WeatherlinkIP logger is similar in function to the standard 6510 Weatherlink loggers but is distinguished by two features. First, it has a TCP/IP interface and so connects not direct to a PC but via a standard TCP/IP LAN/network (which also gives the possibility of connecting to a PC at long distance via a TCP/IP link). Second, the 6555 logger is able automatically to upload current weather conditions every minute to a special website run by Davis at www.weatherlink.com which displays your weather online in an attractive visual presentation (see half-size sample image right and live screens at bottom of page), indexed by its position on a world map and also provides further upload and download features. This special upload facility does not require a local PC at all and is therefore the very simplest method of getting your weather data online in an automatically updating presentation. But it is still also possible, if you wish, to have a local PC and do all the local logging and processing of your weather data that the standard 6510 logger allows (and all at the same time as the automated uploads to the Weatherlink website). More detail on the WeatherlinkIP advanced logger is provided below.
- Special purpose loggers, which make up the family of what Davis refer to as 'streaming' loggers and of which there are currently four distinct models. These loggers
are available only with an RS232 serial interface, ie not in USB form (although they can typically be used with a compatible external serial-to-USB
adapter to connect into a PC that may not have a free serial port). Conceptually, the streaming loggers group into two pairs
that we're terming 'External Control' and 'Special Format Streamers', each pair having related but distinct
applications. Summary details of each logger are shown below (remember that these 'special' features are in addition to
the standard 6510 logger features, although it may not necessarily be possible to use all logger modes simultaneously). Each
logger has a link to more technical detail located on the separate Streaming Loggers page.
- External Control: Loggers able to control external electrical equipment:
- The 6544 Weatherlink for Alarm Output has a separate fly lead from the logger module to a terminal block containing a set of four pairs of external electrical contacts to allow the control of external electrical equipment in response to changing weather conditions. Each pair of contacts can be individually programmed to open or close in response to some particular weather parameter threshold (or combination of thresholds).The 6544 logger is perhaps the most interesting and most generally useful amongst these four streaming loggers. Unlike the Special Format Streamers below, these External Control loggers can perform their special roles at the same time as passing both current and archive weather data to a program running on the linked PC.
- 6560 Weatherlink for Irrigation Control. The 6560 Irrigation Control unit is similar in principle to the 6544 logger but is a very specialised unit that, as its name implies, is intended solely to automatically control irrigation equipment that conforms to a specific interface standard;
- Special Format Streamers: Loggers able to pass real-time text data in special formats to external
devices and programs. Both of these loggers resemble the standard 6510 serial logger at a glance, although there are subtle
- The 6540 Weatherlink for APRS logger is able to continuously broadcast a specific fixed-format text string containing the latest weather readings at regular intervals on its serial port. (This contrasts with the standard logger which generates more complex binary streams of data, but only in response to specific commands from a linked PC). As a result, the 6540 (and 6550 - below) logger can pass its data to non-PC devices such as a ham radio transmitter or to PC programs that - unlike Weatherlink - are not specially designed to request and process data from the Weatherlink loggers. Note, however, that while the 6540 and 6550 loggers can continue to store Weatherlink archive data in the usual way for retrieval by the Weatherlink software at a later time while broadcasting their text strings, they cannot simultaneously pass current weather data to the Weatherlink software and to another program or device - it is one function at a time! The format of the text strings generated by the 6540 logger is exactly as required by the APRS standard for ham radio broadcasting of current weather conditions via a TNC modem. However, the format for the 6540 APRS logger, in particular, contains several standard fields of current weather readings and so could in principle be useful in feeding data to a program or device quite distinct from its intended APRS application;
- 6550 Weatherlink for Emergency Response This is another highly specialised logger intended for use by companies and emergency services that might be involved with spills of hazardous chemicals. In outline, operation of the 6550 logger is similar to the 6540 APRS logger above, but the text output strings from the 6550 logger is in a special format compatible with the CAMEO suite of software programs used by emergency response teams;
- External Control: Loggers able to control external electrical equipment:
WeatherlinkIP data logger - introduction
The 6555 WeatherlinkIP’s key feature is that it has an Ethernet interface instead of the serial (RS232) or USB interface of the standard 6510 series Weatherlink loggers and so typically connects to a network rather than being directly cabled to a PC. As a result, the WeatherlinkIP logger introduces major new options and brings added flexibility and ease-of-use to the wide range of data logging configurations now on offer for a Davis Vantage Pro weather station.
The 6555 logger can upload both current conditions and logged/archive data to a PC or remote server in any of three configurations:
- To a local Windows PC – ie as other Weatherlink loggers but with communication across a Local Area Network (LAN);
- To a remote Windows PC, for example over a long-distance Internet link;
- To a dedicated server at Davis, which runs the website www.weatherlink.com (see also below), providing the simplest possible way of viewing your weather data online;
While some of these features – such as long-distance data links – have been possible previously, they have required substantial technical expertise and added costs to implement. With WeatherlinkIP, it’s now relatively easy for anyone to set up these various types of data link - a very significant advance.
Appearance and installation
The main body of the 6555 logger is similar to other WL loggers and it fits into the Standard or Envoy VP/VP2 consoles in exactly the same way. (It can be used with older VP1 stations as well as the current VP2 models.) There is a short (10cm) lead from the logger, which terminates in an RJ45 socket – fitted with a green status LED – for connection of the network cable and with a substantial ferrite core midway as an anti-interference measure. This makes the logger lead bulkier than on the standard loggers but not obtrusively so. Note that because of the extra power draw of the TCP/IP interface, the console must always be on supplementary power (ie typically the standard mains adapter) for the 6555 logger to be active – internal batteries alone are insufficient.
The WeatherlinkIP logger should be compatible with the vast majority of networks, but formally requires the following two conditions in order to be able to upload its data to the weatherlink.com website:
- Able to see a DHCP server in order to acquire an initial IP address;
- Access out on to the Internet via an open port 80 (outbound & inbound);
Virtually all private networks will meet these two conditions. For larger networks in organisations, please consult your network manager if in any doubt.
The 6555 logger will typically be connected to a TCP/IP network in one of two ways: it connects either to a standard Ethernet LAN hub/switch via the usual Cat 5 patch cable or, if used as the only network device at a remote weather monitoring station for example, it can connect direct to an Internet router/modem and thence to a phone line (note though that the 6555 cannot be connected directly to say an ADSL phone line, you do need a router/modem to provide the Internet interface). Note that the 6555 logger is not itself a wireless (ie WiFi) device but can connect into a WiFi network if cabled to a suitable wireless access point.
Like all network devices, the 6555 logger needs an IP address to identify itself and is set by default to acquire its address automatically by DHCP when first connected to the network. In general your modem/router should provide this DHCP service automatically but, if you should prefer to do so, a fixed IP address can readily be assigned (provided an initial IP has been assigned via DHCP).
Once installed, there are two distinct ways to view the logger’s data output:
- On the special Davis website (www.weatherlink.com) launched specially for use with the WeatherlinkIP logger - see below;
- In the traditional way via a copy of the Weatherlink software or other compatible third-party software. (NB Please note that third-party software must explicitly support the 6555 logger for full and robust logger operation - compatibility with the 6510 series of Weatherlink loggers alone is insufficient. The VirtualVP utility (v1.2.1 and later) is now compatible with the 6555 logger and should provide a workaround for interfacing the 6555 logger to otherwise incompatible software programs);
Important Note: It should be appreciated that the IP logger is not a server for weather data - it can only support one request for data at a time and any attempt to fire multiple simultaneous requests at the IP logger will result in a confused logger that may need the console to be rebooted. In other words, the logger must only be expected to undertake one task at any one time whether this be uploads to weatherlink.com or to service data requests from local software. The Davis Weatherlink software is specially written to co-exist happily with uploads to weatherlink.com but other third-party software may not play as happily. As noted above, use of the Virtual VP software may provide a solution if your application calls for two or more applications to access the IP logger's data simultaneously.
The Weatherlink.com website
The website at www.weatherlink.com is the special high-capacity site that receives automatic data uploads from all 6555 loggers around the world .(NB This upload is enabled by default but can be disabled if preferred.) It is also the only website to which the special summary 6555 uploads can be directed. Just to make this point clear, it is solely the special automatic data uploads that are always directed to weatherlink.com. A 6555 logger can be contacted in the standard way by a PC via any authorised LAN or longer-distanceTCP/IP link that has a known (or forwarded) IP address for general-purpose data uploads; software running on the linked PC can then upload web pages to any nominated web server - none of this standard flexibility is lost with the 6555 logger.
- Browse to www.weatherlink.com;
- Click on the Weatherlink Station Map link in the top right corner;
- Wait a few moments for the world map to finish downloading and drawing;
- Click on a marker for a 6555 weather station near you. (NB The balls represent groups of markers too close together to show separately on the map. If you click on a ball the map will zoom in. Repeat this process until you can see single stations, which look more like a hot-air balloon than a ball);
- Click on a single station of interest and you'll see a dialogue balloon with summary weather conditions and also a further link on the title line;
- Click on the title link which will take you through to the full current conditions screen for that station - this is the 'My Weather' screen;
- There is a second screen for every station that shows highs and lows for today so far - click on the Summary link at the top right to see this;
New 'current conditions' data is uploaded to the Weatherlink server from your logger every minute of every day. (NB The standard web page is set to auto-refresh itself but only every 5 minutes so as not to put too great a load on the Weatherlink server. But if you force a page refresh/reload and look at the timestamp, you'll see that there is new data uploaded every minute.)
The greatest virtue of the 6555 logger is that all of this website capability is available very simply. Literally all that's necessary for most users is: (i) to register your logger at the Weatherlink website so that it knows where in the world you're located; and (ii) set up the weather station and just plug the logger in to a network point connected to the Internet. Within a couple of minutes, your own data should start appearing on the Weatherlink world map and updating automatically!
It's difficult to imagine how setting up an automatically-updating weather reporting website could be made much easier. You can include links directly to your own station on your own web pages and also, if you wish and have a little technical know-how, include the data presentations directly on your own website by coding what's called an iframe in the HTML of your web page.
And, in addition to these 'Summary' and 'My Weather' data views, the Weatherlink website provides further features too, including:
- Upload of the latest set of Weatherlink archive data every hour. Archive data is the set of logged weather records for your station that accumulate in your logger and that give a detailed history of your weather conditions at eg 5 or 10 minute intervals (according to settings). It is possible to use the Weatherlink website as a staging post for archive data, from where it can be downloaded to any authorised PC anywhere in the world for long-term records-keeping and analysis. (This uses what Weatherlink calls a web weather station.);
- Automatic uploading of your data from the Weatherlink website to other collaborative websites that share the world's weather data such as Weather Underground and (for schools) the GLOBE project;
- Alarms: The Weatherlink website can be set to recognise when any alarm condition that you have set on your Vantage console has been triggered. It will then send you an alert email to a nominated email address. If you were to direct this email to an SMS gateway (subscription required) then a text message could be sent to a nominated cellphone whenever the alarm condition was raised;
These are just the features available right now - the Weatherlink website is a relatively new initiiative and we're sure that Davis will be adding further features in the future.
Weatherlink.com - Sample Screens
Shown below are live samples of the two main screens available for viewing your own weather data automatically uploaded by a 6555WeatherlinkIP logger on weatherlink.com. These samples are displayed in HTML iframe constructs in exactly the same way that you could use for yourself on your own web pages.
On a separate web page we also have an interesting illustration where weatherlink.com data presentations from five separate locations around our base in Cambridgeshire (UK) are shown in a tabbed container for easy switching between each location.
The individual images below are showing the current weather at our base in Ely and should update automatically every 5 minutes. The first (upper) image shows our current weather conditions and the second images shows a summary of today's conditions so far, including today's highs and lows.