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upon if many different networks are used. The third method is being set by the GPRS gateway you are
connected to.The GPRS gateway will always take priority over other methods if set.
Network selection
There are two factors that influence the network selection
If you have chosen ‘carrier select’ and have actually selected a network to operate on. When in this
mode, it will attempt to connect to the network that you have selected when powering on the
modem. If it is unable to connect for any reason, it will fall back to the automatic selection that is
dictated by the SIM card.
The SIM card
– This has a table (the PLMN table) built in that dictates which networks it is allowed
on. In automatic mode, it will follow whatever data is present in the table.
4.4
Types of Digital Inputs
Normal
This sampling method occurs when you have at least one channel configured as analogue input in addition to
at least one digital. It will wake up at each wakeup interval and sample both analogue and digital inputs in the
same way a normal analogue input is sampled. This will take a longer period of time, so battery life must be
considered if checking very frequently (once per minute for example).
Quick
If only digital inputs are configured then it will use this sampling method. Every wakeup interval it will very
quickly sample the state of each input, taking a few milliseconds per input. Because of the dramatically reduced
sample time it will use far less power if sampling frequently.
Instant
These only occur when digitals are programmed on channels 5
– 9 using the expansion board. These will be
continuously monitored by the expansion board.
4.5
Before you start
Please make sure you have the following to hand
4mm Allen key
A SIM card with at least the ability to send a text message (see 3.3)
A battery or appropriate power source (see 3.2.1)
4.6
General
With the power connected press either the right or the down button to ‘wake the unit up.’ Enter the PIN (default
= 1234) followed by the right arrow. Navigate around the menu. Use the menu to check signal strength, look at
inputs, check the configuration and much more. Some of the common uses for the display are:
Checking the signal strength (System > Get config / signal)
Select external antenna (System > Antenna
Checking the readings from the sensors (Channels > Channel # > Read Now)
Rotating the display (System > LCD Orientation)