Transmission Range; General Information About Wireless Transmission - JUMO Wtrans p Betriebsanleitung

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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 inversely
proportional 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:
• Ferroconcrete 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:
Material
Wood, plaster, glass (uncoated)
Brickwork, press boards
Armored concrete
Metal, aluminum lamination
When using the antenna holder for wall mounting for the receiver, 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, behind concrete walls, or behind concrete ceilings, the
antenna must always be installed with the receiver holder for wall mounting and antenna cable pointing
in the direction of the transmitters.
4 Transmission range
Permeability
90 to 100 %
65 to 95 %
10 to 90 %
0 to 10 %
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