Duco Intelli Air Valve Serie Manuel D'utilisation page 79

RF components have a maximum free-field range of 350 metres. This
distance will be much less in a building because of obstacles so you
will need to allow for features such as walls, concrete and metal. All
slave components (except those which are battery powered) also act as
repeaters. Signals from components that are unable to make a (strong)
connection with the master component are forwarded automatically
via no more than one other component (= hop point). Please refer to
information sheet RF communication (L8000001) at www.duco.eu for
further information.
Power supply
Frequency
Maximum distance
Maximum number
of components
DUCO RF
350 m, free field
(less through obstacles)
Up to 25 wireless components in a single system
ENGLISH
230 VAC
868 MHz
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