User Manual

Remote access
Technical details
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Use of mobile telephone networks (GPRS/UMTS/LTE)
Several suppliers offer GPRS/UMTS/LTE modems, e.g., modems for private use
and modems for industrial applications (also top-hat rail).
Because of the attenuation of the walls and ceilings, the signal inside a building
can be weak, that is, an antenna must be placed on the exterior of the building,
preferably on the roof.
You can get the best signal strength when the nearest base station of the
mobile network you want to use is not too far away and there are no large
obstacles between the base station and the modem's antenna (line of sight).
Directional antennas improve the transmission quality, but must be optimally
directed towards the base station.
The antenna cable between the modem and the antenna must be short,
otherwise the signal is too weak. Observe the manufacturer's information on
the cable type and maximum length. Antenna cables may not be bent or
pinched too severely. The mobile modem must be placed near the optimum
antenna location. The length of the cable to the IP network is not that critical.
The mobile network operator provides the SIM card. SIM cards come in various
sizes, depending on the modem. Choose the correct SIM card.
The modem is connected to the IP network. The safety measures depend on
the modem.
GPRS modems with an RS-232 connection can be connected to some PX
controllers using a USB-RS-232 converter.
RF-based access networks
Since there are different technologies, an RF-based access is only implemented
in tight cooperation with the network operator. We recommend that you strictly
follow his guidelines.