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U426_flowtherm Ex_B_e_171206
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Example for quantity = 03
01:000.50m/s, 00010Hz
02:010.00m/s, 00350Hz
03:040.00m/s, 01770Hz
If the frequency measured value is greater than in the last pair of values, then the velocity value is
calculated. However, this means that the measurement uncertainty increases as this value is then outside
the calibrated range. The measuring range in the serial no. and technical data sheet must not be
exceeded, as this may cause permanent damage to the vane wheel! (for further information refer to
5.3.1.2)
Settings for vortex sensors VA:
5.3.7
VA – Basic settings
Menu -> Settings -> Sensor -> VA Input ->
Basic settings
The connected vortex sensor determines the parameter type.
5.3.7.1
Type
Setting the type of vortex sensor:
Refer to the relevant technical documents for selection options.
Selection: KKZ
= the calibration number (KKZ) is individually determined for each sensor
and modifies the basic characteristics
KKZ: enter as an 8-digit figure, in which each digit has a 0..9..A..F range
(hexadecimal = 16 possible variables).
The actual KKZ can be found in the technical data sheet, calibration
certificate or directly on the sensor
Pairs of values = special calibration characteristic specifically matched to the measuring task
based on up to 30 supporting points. Entering or amending the points, see
under 5.3.11.
The actual pairs of values are documented in the technical documents.
5.3.8
VA - Measurement settings
Menu -> Settings -> Sensor -> VA Input -> Measurement settings
The measuring task to be carried out determines the parameter, section and profile factor to be set.
5.3.8.1
Section
Setting the measuring section for measuring in pipelines for flow rate display:
Selection:
Circular
= for pipes with circular section
di/mm: enter the ID in mm
Rectangular = for pipes with rectangular section
a/mm: enter the inner surface a in mm
b/mm: enter the inner surface b in mm
5.3.8.2
Profile factor
The profile factor PF specifies the ratio of mean flow velocity in the measuring section and the flow velocity
measured from the sensor. Requirements are: centric sensor positioning, non-rotational inlet flow and
adequately dimensioned input/output sections. (See also Documents U155 and U206).
