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Non-linearity correction functions as an intermediate process between the receiving of input
pulses and the calculation of totals; therefore all subsequent processes such as Rate
calculation, analogue output calculations, and pulses/alarm outputs are also corrected
according to the settings programmed for the non-linearity correction.
The non-linearity correction function is programmed using up to 10 frequency points, and a
K-factor for each frequency point. Not all 10 points must be used, however a minimum of 2
points is required. Below the minimum frequency point the instrument will use the K-factor
entered for the lowest point, similarly above the maximum frequency point the instrument will
use the K-factor entered for the highest point. Linear interpolation is used between frequency
points.
If any frequency in the programming menu is entered as zero Hz then all remaining
frequency points will be disabled; i.e. if data is entered for points ‘0F’ to ‘4F’ and point ‘5F’ is
entered as 0Hz, points ‘6F’ to ‘9F’ will not be used. Once the non-linearity correction function
is enabled the general K-factor entered at Level 5 of the program is disabled; if the non-
linearity correction is later disabled the instrument will revert to the general K-Factor.
Data for entry of Non-Linearity Correction is available for Flomec meters when purchased
with a multi-point factory calibration. Alternatively NLC data can be obtained with a field
calibration of the meter.
5.8 Digital Output
The digital output function is configurable for either a pulse output according to totalised
flow, or an alarm output according to flowrate. The pulse output can be configured for an
unscaled pulse or a scaled pulse, and the alarm can be configured for notification of high
flowrates, low flowrates, or a combination of both.
5.8.1 Un-Scaled Pulse
The unscaled pulse output, also commonly referred to as a ‘repeater pulse’ is enabled by
selecting ‘UNSCALED’ in the digital output configuration menu.
5.8.2 Scaled Pulse
The scaled pulse output is enabled by selecting ‘SCALED’ in the digital output configuration
menu. Configuration of this output is accomplished by entering the number of units per output
pulse; e.g. 10 Litres/pulse, 0.1kgs/pulse, etc. The engineering units configured for the Total
display are used to specify the settings for this output. The range of available settings for this
output are from 0000.01 units/pulse up to a maximum of 9999.99 units/pulse.
As there is a frequency limitation on the scaled pulse output of 100Hz it is preferred to
configure the scaled pulse output to keep the output frequency below this limit. If it is
necessary for the scaled pulse output to operate at greater than 100Hz the instrument will
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General