JUMO Wtrans E01, Руководство по эксплуатации

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4 Transmission range
4 Transmission range
4.1 General information about wireless transmission
Wireless signals are electromagnetic waves whose strength becomes weaker on their path from the
transmitter to the receiver (this is referred to as path attenuation). The field strength reduces at an in-
verse proportion to the square of the distance between the transmitter and receiver.
In addition to this natural range restriction, a reduced range may also be caused by the following:
•
Reinforced concrete walls, metallic objects and surfaces, heat insulation, or heat-absorbing windows
with a vapor-deposited metal layer reflect and absorb electromagnetic waves, meaning a dead spot
is formed behind them.
• Metal tubes, chains, etc. on the transmitter housing; therefore, do not fasten any metallic objects to
the transmitter housing.
• Insufficient spacing between several transmitters; therefore, ensure a minimum spacing of 20 cm.
• The antenna is installed at an insufficient height; therefore, install as high as possible above the
ground and ensure there is a line of sight between the transmitter and receiver.
The following values are reference values concerning the permeability of wireless signals:
The range between the transmitter and the receiver in an open area is up to 300 m. Optimum reception
is achieved when a line of sight can be established between the transmitter and the receiver.
If the receiver is mounted in a control cabinet or behind concrete walls or concrete ceilings, the antenna
must always be installed with the holder for wall mounting and 3 m antenna cable for the receiver pointing
in the direction of the transmitters.
Material Permeability
Wood, plaster, glass (uncoated) 90 to 100 %
Brickwork, press boards 65 to 95 %
Armored concrete (reinforced) 10 to 90 %
Metal, aluminum lamination 0 to 10 %