VEGA VEGAPULS 41 Profibus PA - Manual (Page 12)

12 VEGAPULS 41 – Profibus PA
27292-EN-041227
1.6 Antennas
The antenna is the eye of the radar sensor.
The shape of the antenna, however, doesn’t
give a casual observer the lightest clue on
how carefully the antenna geometry must be
adapted to the physical properties of electro-
magnetic waves. VEGAPULS 41 radar sen-
sors are equipped with a completely
encapsulated antenna.
PTFE is commonly found in hygienic applica-
tions. The small plastic cone of the
VEGAPULS 41 radar sensor, operating as
antenna, consists of a TFM-PTFE material.
This is a fluorothermoplast, which has addi-
tional distinct advantages compared to PTFE,
such as, e.g., reduced load deformation,
denser polymer structure as well as a
smoother surface (Ra < 0.8 µm). The other
known advantages of PTFE, such as, e.g.,
high temperature resistance (up to 150°C),
high chemical resistance as well as resist-
ance to brittleness and ageing are still
present or have even been enhanced.
Perfluorelastomers and fluorothermoplasts
are resistant to virtually all chemical media
such as, e.g., amines, ketones, esters, acids
(sulphuric acid, phosphoric acid, hydrochlo-
ric acid, nitric acid), alkalis (caustic soda),
oxidants, fuels and oils. Beside their use in
the chemical industry, these materials are
being applied more and more in sterilisation
and pharmaceutical technologies. The only
limits to these materials are in applications
with fluorine under high pressure or with
liquid alkali metals (sodium or potassium),
where explosive reactions may occur.
Features
• Application preferably for liquids in storage
tanks and process vessels with increased
accuracy requirements and in corrosive
environments.
• Measuring range 0 … 10 m
• Ex approved in Zone 1 (IEC) or Zone 1
(ATEX) classification mark
EEx ia [ia] IIC T6.
• Integrated measured value display.
Types and versions
1.5 Type survey
VEGAPULS 41 sensors are manufactured
with process connection G 1½ A or 1½“ NPT.