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SITRANS LR200 with mA/HART
Operating Instructions, 05/2019, A5E32337676-AE
207
speed of light
the speed of electromagnetic waves (including microwave and light) in free space. Light
speed is a constant 299, 792, 458 meters per second.
stilling-well
see stillpipe.
stillpipe
a pipe that is mounted inside a vessel parallel to the vessel wall, and is open to the vessel at
the bottom.
TVT (Time Varying Threshold)
a time-varying curve that determines the threshold level above which echoes are determined
to be valid.
two wire radar
a low-energy radar. Can be loop powered, analog, intrinsically safe 4 to 20 mA, or a digital
(BUS) transmitter.
waveguide antenna
a hollow, metallic tube that transmits a microwave signal to the product target.