Page 34 MiniRanger Plus 7ML19981CJ01
Functional
between the fixed value and the actual temperature surrounding the
transducer will cause an error in measurement.
Sound Velocity
The MiniRanger Plus can be calibrated to compensate for sound velocity
error in fixed temperature, homogenous atmospheres.
The basis is to physically measure the level (measuring tape or sight glass)
and enter the value via P651. The MiniRanger Plus then calculates the
sound velocity by comparing the entered physical measurement to its own
ultrasonic measurement.
Blanking
Near blanking (P800) is used to ignore the zone in front of the transducer
where ringdown
* or other false echoes (e.g. standing wave, ladder rung)
appear as an echo during the receive cycle. This is usually indicated by an
incorrect high level reading and can be overcome by increasing the near
blanking from its factory set value.
* ringdown is the natural decay of transducer vibration after the transmit
pulse ceases.
Far end blanking is a feature that ignores the zone below the zero or empty
level where false echoes can appear at levels that interfere with the
processing of the true echo.
ringdown or
false echo
true echo
(level)
false echo
0
level
far end
blanking
P800 near
blanking
end of
transmit
empty distance to transducer
P006
range
range extension
(P801) as % P006
typical processing signal
To Next Page
Loading...
