User Manual

10 APPENDIX
130
OPTIWAVE 7400-24 C
www.krohne.com 12/2015 - 4004901901 - MA OPTIWAVE7400-24 R01 fr
10.4 Glossary
D
E
F
H
I
L
Dead zone
Dead zoneDead zone
Dead zone Non-measurement zone.
Dielectric constant
Dielectric constantDielectric constant
Dielectric constant An electrical property of the product to be measured used in Radar
measurement. Also known as εr, DK and relative permittivity. Defines the
strength of the wave reflected back to the device's signal converter.
Distance
DistanceDistance
Distance The distance from the face of flange to the level (1 product) or the surface
of the top product (2 or more products). See the diagrams at the end of this
section.
Drop antenna
Drop antennaDrop antenna
Drop antenna A new generation of antenna made of PP or PTFE. It has an ellipsoidal
shape for a more precise emission of radar signals.
DTM
DTMDTM
DTM Device Type Manager. A driver for use in the PACTware™ program. All data
and functions of the device are included in it.
Electromagnetic compatibility
Electromagnetic compatibilityElectromagnetic compatibility
Electromagnetic compatibility Defines how much a device influences or is influenced by other devices that
generate electromagnetic fields during operation. Refer to European
standard EN 61326-1 for further details.
FMCW
FMCWFMCW
FMCW Frequency-modulated continuous-wave radar technology. The signal is
continuously present, but the frequency is modulated, usually in
successive linear ramps over time (frequency sweeps).
Hazardous area
Hazardous areaHazardous area
Hazardous area An area with a potentially explosive atmosphere. Trained personnel can
install and use a device in this area. The device must be ordered with the
appropriate options. The device requires approvals (ATEX, IECEx, FM, CSA,
NEPSI etc.) related to site specifications. You can find more data about
hazardous areas in the Ex Manuals and Ex Certificates of Compliance.
Horn (cone) antenna
Horn (cone) antennaHorn (cone) antenna
Horn (cone) antenna A common antenna for most applications. It is used for the controlled
emission and collection of radar signals.
Hygienic antenna
Hygienic antennaHygienic antenna
Hygienic antenna An antenna made of a material that agrees with FDA regulations. It can be
supplied with common hygienic process connection options (Tri-Clamp
®
,
BioControl
®
, SMS, ...).
Interference signals
Interference signalsInterference signals
Interference signals False radar reflections.
Level
LevelLevel
Level Height from the bottom of the tank (user-defined) to the surface of the top
product (Tank height – distance). See the diagrams at the end of this
section.