WeatherlinkIP data logger - introduction

The Davis 6555 WeatherlinkIP (WLIP) data logger is a new member of the family of Weatherlink (WL) loggers that has just been released and is now in stock. The 6555’s key feature is that it has an Ethernet interface instead of the serial (RS232) or USB interface of the other 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 settings:

• 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, 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 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 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 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.

Once installed, there are two distinct ways to view the logger’s data output: on a new Davis website (www.weatherlink.com) launched specially for use with the WeatherlinkIP logger or in the traditional way via a copy of the Weatherlink software or other compatible third-party software.

Davis Weatherlink website

The simplest and quickest way of viewing your weather data is via the Weatherlink website. There is no need to do any website design at all – the data presentation is automatically and attractively done for you. Anyone who has been advised of the web address will be able to see your data without any further work on your part. At present the format is relatively limited, but no doubt the options will be expanded as the number of users to provide feedback increases and as Davis develop the site further.

To set up your own area on the Weatherlink site you need to create an account, which is tied to the specific ID of your WLIP logger. (You need to have a WLIP logger before you can create an account.) Creating this account is very simple and once your logger is correctly attached to an Internet connection, it will automatically start uploading data to the website at 1-minute intervals. So literally within a few minutes of creating the account and connecting the logger, live weather information from your own weather station will start appearing on the Weatherlink website and update itself automatically. (But if you hate the idea of automatic uploads, this feature can be turned off if preferred.)

There are currently just two data presentations available. One screen (above - click for latest data) shows the latest weather report received and the other (right) shows summary data (highs/lows etc) so far for the current day.

The Weatherlink site contains a world map showing the locations of all  the 6555-equipped stations currently reporting data.

There are a couple of important further features of the current website implementation. First, the logger uploads archive data every hour to the Davis site, from where any authenticated PC can download the data again. The Weatherlink site can therefore act as a staging post for archive data collected at a remote site for example – there’s no necessity at all in fact for you to contact the WeatherlinkIP logger directly in order to download archive data; this can all be done via the Davis site if you wish, which can also therefore act as a backup store of your recent archive data.

Second, you can set your Weatherlink website account to automatically transfer your latest weather data to other worldwide data-collation sites; CWOP and (imminently) GLOBE are the two sites on offer initially but doubtless others, including Weather Underground, will be added in due course.

The Weatherlink website account is also going to offer a further valuable feature. If you have automatic uploading of current conditions enabled, the website will send you an email of summary conditions up to thrice daily and/or when any alarm conditions that you set on the VP2 console have been triggered (eg air temperature <2°C). If you were separately to organise an inexpensive account at an email-to-SMS gateway and direct your alarm emails to that gateway then the alarm message could be relayed to your phone by SMS.

So, overall, the Weatherlink site provides many of the basic features for sharing your own weather data with others without ever needing to set up special software – once an account is set up at the Weatherlink site, your data can be online within minutes of connecting the logger, a feature that may appeal especially to busy or inexperienced users such as schools.

Weatherlink v5.8 software

Of course, many users will still wish to have access to the comprehensive features for analysing and presenting their weather data and for uploads to their own website that the Davis Weatherlink software offers. The latest v5.8 software (it is essential to use this version to establish contact with the WLIP logger) is supplied in the WLIP box. As well as adding the capabilities to talk directly to the WLIP logger and giving the option to set up ‘web stations’ to accept archive data downloaded from an account at the Weatherlink website, v5.8 is able to do all that v5.7 could do. In other words, the TCP/IP link is simply the mechanism by which raw data gets to the Weatherlink software, which retains all its standard features, including the ability to upload data and images to your own website and using your own custom web page designs.

The v5.8 software contains an expanded Communications Port set-up dialogue whereby TCP/IP can be set as the interface to use to communicate with the WLIP logger. There is then an option to acquire data via the local network or via a remote TCP/IP link or via a download of archive data from the Weatherlink site to a specially-created location within your own copy of the Weatherlink software - what is now known as a ‘web station’.

Communications over a LAN are simple to set up even if the terminology may be a little unfamiliar to those inexperienced with networks. For example, there is a Find button that can locate a WLIP logger on the LAN even if its IP address is not known. Local use across a LAN is essentially indistinguishable in response terms from having the logger directly connected to the PC.

The option to contact a WLIP installation over a long-distance TCP/IP link such as the Internet is a powerful new feature. It is possible for the Bulletin mode of Weatherlink to be displaying live data, ie showing wind gusts etc, from a VP2 station located potentially hundreds or thousands of miles away. The one caveat here is that if the ISP account for the remote Internet connection involves a rapidly-changing dynamic IP address then it may be difficult to sustain the connection. However, even on dynamic IP allocation, the IP addresses are often ‘sticky’ (ie may change relatively infrequently), plus accounts with fixed IP addresses are still easy to acquire at a small premium. But if you're stuck with a dynamic IP address from your ISP, it's fairly easy to work around this by setting up a dynamic DNS service (see eg www.dyndns.com) and accessing the remote 6555 logger via a text URL rather than a numeric IP address - the Weatherlink software does support this approach.

Because the 6555 logger is new and connects using TCP/IP rather than serial or USB ports, compatibility with third-party software (Weather Display, VWS etc) is variable at present. A new version of Weather Display is now available that does offer compatibility with the 6555 logger, as does VPLive. (Note that there may as yet be some residual limitations, for example as to whether the 6555 logger can continue to upload automatically to the Weatherlink website at the same time as streaming data to other software. We expect software versions offering full compatibility to appear very quickly.)

Price and availability

The official list price for the WeatherlinkIP logger is in line with the other specialist Weatherlink loggers at £310 inc VAT and this logger is now available from stock.

Conclusions

The 6555 logger with its TCP/IP interface is a real innovation that provides important new logging options for VP/VP2 weather data while significantly simplifying implementation. Users will need to decide whether the extra cost of the 6555 over the standard 6510 series loggers, which remain available of course, justifies itself, but the 6555 could appeal to several specific groups of users:

• Anyone looking for the simplest possible way of sharing their weather data via a public website;
• Those wishing to run a live weather-reporting website without leaving a PC running 24/7 nearby to the weather station. Such users can also take advantage of having an alarm message sent automatically by email or SMS if weather conditions pass a set threshold;
• Users with their own local network (LAN) who might wish to inject the weather data into their LAN at one place and view and manage the data on a PC elsewhere;
• Those wishing to actively monitor weather conditions at a location remote - potentially thousands of miles away - from where the managing PC is sited. (Remember though that supplementary power and a data link such as an ADSL phone line will be needed at the remote location.);

Here at Prodata Weather Systems, we have been involved in detailed testing of a pre-release sample of the 6555 logger and are confident that already we’ve built up significant expertise in the setting-up, general capabilities and software compatibility of VP2 weather monitoring systems that use the WeatherlinkIP logger. If you’re interested in the possibility of buying or using a 6555 logger for your VP/VP2 system – new or established – then for genuinely informed and expert advice please contact us by email or phone (01353 664175 in the UK). Comments and any outstanding questions on this brief review are also welcome.