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The two outputs are the two right hand side three way connectors. The internal relays for the outputs are
optional and are not supplied in the Metron as standard, though the connectors will still be present.
The outputs should not be used for switching high voltages (mains voltages). They are each rated to switch 2A
at 30V DC.
3.3
SIM cards and Carriers
SIM card selection is often the cause of connectivity issues. There are a number of requirements needed from
the SIM card for it to operate correctly
It is the correct type (full size SIM, not micro or nano SIM)
It does not have a PIN enabled on the SIM
There is network coverage where you plan to use it
Roaming is enabled if using outside of the country of purchase
The APN, username and password for the SIM contract are correct.
Replacing the SIM
1. Open the lid to reveal the SIM card holder.
2. Note the orientation of the SIM socket, using the drawing behind the socket
3. Slide the SIM into the socket
4. If the installation is going to be moving or vibrating, you may wish to use a piece of high-tack tape across the
back to prevent the SIM from moving in these conditions
Manually selecting a carrier
If you are using a roaming SIM that is capable of using multiple carriers in the installation location, then you
may want to select a specific carrier to use by default. This may also be especially useful if there are two weak
differing networks in the area and the unit switches between them frequently. To do this, follow these
instructions.
1. Verify if you have a roaming SIM. Do not proceed if you do not.
2. Go to the menu option ‘System’ and then ‘Carrier Select’
3. It will take a little while to boot the modem if necessary and query the networks
4. A list of operators that are available in the area will appear. It does not mean you will have permission to
connect to them all.
5. Select the operator that you wish to use in the future.
If the unit is not able to connect to the carrier that you have selected next time, it will fall back to automatic
selection.
3.4
External Antennas
The Metron2 has an integral antenna. The system has been designed to gain optimum signal strength to the
mobile phone network but it is possible to use an external antenna. If you are in an area of poor signal strength,
or mounting the unit inside a metal enclosure then you may need to connect an external antenna. If using an
external antenna then select this option when programming or use the menu option to enable.