User manual

Using with Campbell Scientific Dataloggers
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 Can synchronise the datalogger clock to Internet time
(networktimeprotocol).
 Can send data to other loggers via IP (Send/Get variables, files and data)
 Can do a normal callback to a Loggernet server (send variables)
 Can do a one way transmission to Loggernet or another logger (Senddata)
 Can open virtual serial ports to other dataloggers or sensors via the IP
network.
Only standard Pakbus communication with Loggernet is possible if
using the TCP/IP function built into the modem. The other
advanced communications options require a datalogger capable of
running its own TCP/IP function. Those loggers currently include
the CR800 series, CR1000 and CR3000 dataloggers.
5.1 Network coverage
The same considerations as outlined in Section 4.1 above apply in terms of the
type of network and signal strength required for GPRS connections. In general to
sustain a GPRS connection for long periods, slightly higher signal strength is
required compared to use for GSM dial-up connections.
The COM100 is essentially a 2G modem, so will not use 3G network
connections. It does however support some features of enhanced 2G networks
called “EDGE”. Where that is enabled on the local cell, slightly higher data
transfer rates may be achieved.
When testing for coverage and signal strength using a handset if possible limit the
phone to non-3G operation and check both the signal strength and availability of
GPRS or EDGE data signals, which are often indicated by a “G” or “E” symbol
on the display.
5.2 GPRS network contracts and costs
The modem needs to be used with an airtime contract that allows GPRS
communications. Some SIMs are sold as “3G” compatible which means they can
be used in 3G phones too. It is important to check with your supplier that any
SIM supplied will work in a GSM/GPRS phone and that GPRS operation is
enabled and any 3G compatibility does not slow down the log-on process to the
network (which has been seen on UK O2 networks).
When buying a contract for GPRS the standard offering in Europe is for a
connection where you are allocated a dynamic, private IP address. This can be
used with Campbell dataloggers and is often the cheapest way to get a system up
and running. However, when operating in this way you can only have a limited
numbers of PCs or loggers connected to one logger and you lose some of the ftp
server, http and some other functions as the logger cannot accept unsolicited calls
made to it because it is on a private network behind a firewall.
For full flexibility specialist suppliers provide a service to give individual devices
a fixed IP address, which can either be private (accessed via a VPN connection) or
a public address on the internet. In the UK the suppliers include Wireless Logic,
Wireless Innovation Ltd and Wyless.net. Such companies are suitable for larger
scale networks and provide additional on-line tools to let you monitor the state of
your GPRS connections, traffic use etc. Alternative suppliers can be found by
NOTE