Water bottom measurement
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Instruction manual VITO Page 40
5.3 Operation
5.3.1 Display
For operation of the display and the information on it, refer to the instruction manual of the applicable level gauge
or 877 FDI. Below, only an overview is given which display format gives information about the water bottom
measurement.
Water level and status
5.3.2 Water above / below probe warning
Automatically a warning is given when the water level is too low or too high for the probe to measure correctly.
• The water above probe status (AP) is displayed and signalled in the water level record when the water
level is within 1% of the probe length (item WP) from the top of the water probe.
• The water below probe status (BP) is displayed and signalled in the water level record when the water
level is within 1% of the probe length (item WP) from the bottom of the water probe.
Around these warnings there is a hysteresis of 0.5 % of the probe length (item WP).
5.3.3 Data items
Table 5 – 2 lists a number of data items. They contain measured data, verification data and error data. The
verification data can be used to check the results of certain steps in the measuring sequence. The diagnostic data
provides low level error information about the water level measurement (refer to section 5.4).
LH
MX
Measured / Water level, preceded by two status bytes (refer to section 5.4.2)
Calculated data Water ullage, preceded by two status bytes (refer to section 5.4.2)
Measured capacitance from 765/766/768 VITO water probe
Verification data Refer to description at section 5.4.3
FH
H0
Diagnostic data Error water request (refer to section 5.4.1)
Fatal HCU/ICU_HPI errors
Last fatal HCU/ICU_HPI error
Table 5 – 2