Siemens SIMATIC MOBY D - Page 52

Planning the MOBY D system
4.3 Installation guidelines
MOBY D
52 System Manual, 01/2010, J31069-D0147-A6-7618
Flush-mounting
Flush-mounting Problem
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Flush-mounting of MDS and SLG / ANT Dx
is possible in principle. However, the size of
the transmission window is significantly
reduced. The following measures can be
used to counteract the reduction of the
window:
Remedy:
$17b
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Replace the non-metal spacer below the
MDS with a larger one.
MDS and/or SLG / ANT Dx must be at least
50 mm higher than the surrounding metal.
(At a distance x ≥ 600 mm from metal, the
field is no longer noticeably affected.)
Remedy:
$17'[
EE
DD
Increase the non-metal distances a and b.
As a rule of thumb:
 Select values for a and b that are larger
by a factor of 2 to 3
 Increasing a and b has a greater effect
for antennas/MDS with a large limit
distance than for antennas/MDS with a
small limit distance.