FNM alpha SM 230, User Manual, Page: 67 / 72

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Troubleshooting / Antennas
Sensor module alpha WSN SM 230-G and alpha WSN SM 230
… voltage supply
• Check the state of charge of the battery.
•
If available:
à
Check whether the power supply unit is firmly attached at the
module.
... of the antenna
•
Check whether the antenna is firmly attached.
•
Check the position where the external antenna is mounted. The antenna radiator
may in no case touch conductive parts (e. g. plates, heaters, cable, PC housings,
etc.) or be shielded by these.
Repeater module alpha WSN RM 300-G and alpha WSN RM 300
… voltage supply
•
If available:
à
Check whether the power supply unit is firmly attached at the
module.
... of the antenna
• Check whether the antenna is firmly attached.
•
Check the position where the external antenna is mounted. The antenna radiator
may in no case touch conductive parts (e. g. plates, heaters, cable, PC housings,
etc.) or be shielded by these.
Antennas
When visibility is clear, ranges of up to 400 m are possible by means of stand-
ard antennas between the modules. By means of a gain antenna, receiving and
transmitting properties of the wireless measurement system can be improved.
All antennas for the ISM band 868 MHz can be used in principle. Omnidirectional
antennas with an antenna gain > 0 dBi are recommended. When purchasing an
antenna, mind the required SMA plug at the connection cable.
The antenna radiator may in no case touch conductive parts (e. g. plates, heaters,
cable, PC housings, etc.) or be shielded by these.
If possible, there should be a visual contact to the opposite station.
Mind that all antennas of the modules are operated in the same operating position
(e. g. all antennas are standing vertically).
Electrical devices like computers etc. can generate interference fields that reduce the
range.
If not given otherwise, the limits of the ETSI EN 300 220 and ETSI EN 301 489 will
apply.