Siemens SITRANS LR200 Instruction Manual page 127

frequency: the number of periods occurring per unit time. Frequency may be stated in cycles
per second.
hertz (Hz): unit of frequency, one cycle per second. 1 Gigahertz (GHz) is equal to 10
horn antenna: a conical, horn-shaped antenna which focuses microwave signals. The larger
the horn diameter, the more focused the radar beam.
inductance: the property of an electric circuit by virtue of which a varying current induces an
electromotive force in that circuit or in a neighboring circuit. The unit is a Henry.
microwaves: the term for the electromagnetic frequencies occupying the portion of the radio
frequency spectrum from 1 GHz to 300 GHz.
multiple echoes: secondary echoes that appear as double, triple, or quadruple echoes in the
distance from the target echo.
Near Blanking: see Blanking
nozzle: a length of pipe mounted onto a vessel that supports the flange.
parameters: in programming, variables that are given constant values for specific purposes or
processes.
polarization: the property of a radiated electromagnetic wave describing the time-varying
direction and amplitude of the electric field vector.
polarization error: the error arising from the transmission or reception of an electromagnetic
wave having a polarization other than that intended for the system.
PROFIBUS PA: one of the PROFIBUS family of protocols, specifically tailored for the needs of
process industries (PA = Process Automation).
propagation factor (pf): where the maximum velocity is 1.0, pf is a value that represents a
reduction in propagation velocity as a result of the wave travelling through a pipe or
medium.
pulse radar: a radar type that directly measures distance using short microwave pulses.
Distance is determined by the return transmit time.
7ML19985HP01 SITRANS LR 200 (PROFIBUS PA) – INSTRUCTION MANUAL
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Hz.
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