FNM alpha SM 230, User Manual, Page: 9 / 72

8 9
Product description
The sensor data acquisition is often connected with much installation work (laying of a
multitude of cables in areas that are often impracticable and separated) and / or high
personnel expenditure (manual reading of single sensors, interpretation of the measur-
ing results regarding exceeding of the limit etc.). In both cases, considerable financial
expenses arise.
A reasonably priced, flexible alternative that can be adapted to special requirements is
the sensor network alpha WSN from FMN.
Depending on the measuring interval, a total of up to several hundred measuring points is
possible. In order to be able to achieve a sufficient coverage or a higher range, repeaters
can be used. They extend the range of the wireless measurement system by far.
Modules of the wireless measurement system
Base module
The base module receives the transmitted data of the sensor modules and transfers
these over a RS232, USB, LAN or WLAN interface to a PC or an IP network.
The RS232 interface is available at all module versions.
The LAN or WLAN interfaces make the connection to an Intranet or to the Internet
possible and therewith the worldwide inquiry of the measurement data.
At the combination LAN / RS232 (alpha WSN BM 110), the voltage supply will be realized
over an external pluggable power supply unit or over the LAN connection (PoE – Power
over Ethernet) if an appropriate PoE voltage supply is installed in the LAN.
At the combination USB / RS232 (alpha WSN BM 120), it is possible to realize the voltage
supply over the USB interface. Alternatively, the voltage supply can also be realized
over a power supply unit.
At the combination WLAN / RS232 (alpha WSN BM 130), the voltage supply has to be
realized over an external power supply unit.
Sensor module
The sensor module is for the connection of different sensors.
The acquired data is transmitted to the base module by radio and from there, it is
transferred to a PC.
An inquiry as well as setting of the parameters of the sensor modules from base module
(polling) is also possible.
The voltage supply is realised over an internal 3.6 V battery (lithiumthionylchloride,
size 2/3 A). In case the battery voltage is falling below the minimum battery voltage, a
message is sent to the base station. The battery should be changed then. An intelligent
power management guarantees a long battery lifetime.