Nivus OCM F, Инструкция по эксплуатации

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Instruction Manual
OCM F
page 78 OCM F - rev. 05 / 06.04.2018
Fig. 25-4 Flow velocity h-v-one-point-calibration
Fig. 25-5 Flow velocity h-v-multi-point-calibration
>h-v Calibration< One-Point-Calibration:
Enter a factor in the first line and leave the level set to 0. This factor
is used over the entire level range.
Multi-Point-Calibration:
Level-based multiplication (linearisation) of the measured flow veloci-
ty using multiple calibration factors.
Particularly in very large dimensions the detection range of the veloci-
ty sensor covers only a part of the entire wetted cross section. Here it
is recommended to use this calibration method.
Up to 16 breakpoints can be specified in the table.
>h_crit.< Measuring the flow velocity is no longer possible as soon as the level
falls below a certain level called h_crit.
The level h_crit is pre-determined by the construction of the sensor
as well as the measurement method.
Default setting: 0.065 m (2.56 in)
After initial start-up, the OCM operates using the start values found in
the Manning-Strickler table (see >CAL< / >velocity< / >v-crit determi-
nat.< / >Manning-Strickler<) until it reaches the h-crit value set.
Going through a level range of 9…12 cm featuring a decreasing trend
causes the unit to determine an application coefficient (automatic
activated).
Then the OCM under h-crit operates using the investigated applica-
tion coefficient.
In case of a raised sensor installation position enter +0.065 m as
installation height here.
Example: enter 0.085 m under “h-crit” in case of using a sensor in-
stallation height of 0.02 m.
>h-crit. min< The flow velocity will not be calculated below “h_crit. min” and hence
will be set to 0.