RMS621 Appendix
Endress+Hauser 71
Fig. 28: Splitting Range mode
Mean value computation
Mean value computation gives you the opportunity of measuring an input variable using several
sensors at different points and then getting the mean value from them. This function helps if several
measuring points are required in a system in order to determine the measured variable with
sufficient accuracy. Example: use of several Pitot tubes to measure flow in pipes with insufficient
inlet runs or a large cross section.
Mean value computation is available for the input variables pressure, temperature and special flow
meters (differential pressure).
Correction tables
Flow transmitters return an output signal in proportion to the flow. The relationship between the
output signal and the flow can be described in the curve. The flow cannot always be determined
exactly by a curve in the entire measuring range of a transmitter, i.e. the flow transmitter shows a
deviation from the ideal curve pattern. This deviation can be compensated for with the correction
table.
The correction is different, depending on the type of flow transmitter:
• Analog signal (volumetric, mass)
Table with up to 15 current/flow value pairs
• Pulse signal (volumetric, mass)
Table with up to 15 value pairs (frequency/k-factor or frequency/pulse value, depending on the
type of signal)
• Differential pressure square root/not square root
Table with up to 10 value pairs (flow/factor ƒ)
!
Note!
The points are automatically sorted by the device, i.e. you can define the points in any order.
Make sure that the operating status is within the table limits since values outside the table range are
determined by extrapolation. This can result in greater inaccuracies.
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