Siemens SIMATIC RF200, Системное руководство

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Planning the RF200 system
4.3 Installation guidelines
SIMATIC RF200
86
System Manual, 07/2017, J31069-D0227-U001-A9-7619
Metal-free space
To guarantee perfect functioning of the individual installation versions, all larger metal parts
in the vicinity of the antennas must be removed.
Figure 4-20 Metal-free space, side view (based on the example of a tunnel arrangement on a
conveyor belt)
a approx. half antenna length
b min. 100 mm
c max. 600 mm
Metal-free space
Figure 4-21 Metal-free space, view from above (based on the example of a tunnel arrangement on a
conveyor belt)
Metal in the vicinity of the antennas
If metal in the vicinity of the antennas cannot be avoided, the following must be noted:
● There must be a minimum allround gap of 100 mm between the antenna and metal.
Serious loss of sensing range must be expected above 50 mm. There is no discernible
influence at distances greater than 150 mm from the metal.
● The influence of the metal depends heavily on its size and shape. Thin metal rods have
less influence on the magnetic field than large surfaces.
● Larger metal surfaces (edge length > 50 mm) in parallel with the antennas or labels result
in a short-circuit of the magnetic lines of force. As a result, the labels cannot be read.
● Metal parts under the conveyor belt change the direction of the magnetic lines of force.
Serious loss of sensing range must be expected as a result. Horizontally aligned labels
cannot be read in such cases.