Rosemount TankRadar Rex DAU 2100, Руководство по обслуживанию

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5-1
Rosemount Tank Radar Rex
Chapter 5 Calibration
Service Manual
308012En, Ed.2
May 2013
5. Calibration
5.1 Introduction
Normally a minor adjustment of the Calibration Distance is needed in
order to achieve agreement between measured and actual product level.
(For TRL/2 transmitters the Tank Connection Length (TCL) is adjusted).
A small offset can for example result from deviations between the actual
tank height and the value stored in the transmitter database, or from
differences between various RTG microwave units and antennas.
The calibration should be performed once at the final commissioning,
and does not need to be repeated unless tank conditions are altered.
You can choose to manually adjust the Calibration Distance, or you can
use the Calibrate function in
WinSetup for automatic adjustment.
5.2 Manually adjusting the Calibration Distance
The Calibration Distance can be manually adjusted in order to
compensate for differences between different RTG microwave units and
different antennas. For TRL/2 2900 transmitters the corresponding
adjustment is done by changing the TCL parameter. (For Rex
transmitters the TCL is never adjusted except when non-standard
antennas are used).
If there is a deviation between hand dipped and measured levels, you
may calculate a new Calibration Distance value according to the formula:
New Calibration Distance = Old Calibration Di

L
where

L = observed level (hand dip) - transmitter level reading.
The same formula applies for TRL/2 transmitters if the Calibration
Distance is changed to the TCL parameter.