Burkert Type 8055 - Manual (Page 29)

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to the output. In actual fact there is always a minimum time between the measure acquisition and the
outputs update.
(POS. 3.4) Peak cut off threshold
[PEAK THR=% XXX]
Anomalous signal pick cut off threshold set. This parameter allows setting the maximum value of
deviation of the actual measure sample by comparison with the average one. If the new value is
higher than the set limit, than such a value is “cut” to the limit value. This function is used to make
the meter less sensitive to big perturbations on the flow rate measure, as it may happen when there
are solids in suspension in the liquid hitting against the electrodes determining a high electrical noise.
The permitted values of this function range from 0 to 125 % and are referred to the full scale value.
If this parameter is set to zero the peak detection function is disabled and any new measure ample
will be accepted and processed as it is by the converter.
(POS. 3.7) Automatic scale change enable
[AUTORANGE=ON/OFF]
Enables the automatic change of scale. The meter may have two different working ranges in order to
suit to the variable process conditions. In order to get the best results out of this function it is
important range N.2 is bigger than N.1. When the flow rate increases and reaches the 100% of the
full scale 1, then the meter automatically switches to scale 2. When the flow rate decreases again
reaching a value on scale 2 equal to the 90% of full scale N.1, then the active scale is 1 again.
Allowed values for this parameter: ON / OFF. N.B.: the autorange doesn’t allow using the manual
change of range (see pos. 5.8)
(POS. 3.8) Energy saving enable [E.SAVING=ON/OFF]
This function is used when the instrument is powered by a battery or solar cells, allowing an energy
saving up the 60-80. The energy consumption is controlled by the ratio between the measuring cycles
powering the coils and the cycles without powering the coils. When the flow rate is stable the number
of “off” cycles is higher than the “on” ones, so that the average consumption is strongly reduced. If
the flow rate suddenly changes, then the meter switches on a higher number of measuring cycles, in
order to get a higher response time, switching off the cycles as soon as the flow rate gets back to be
stable. If the flow rate varies below of the “acceleration threshold” (POS.18) percentage value, then
the meter goes on with “off” cycles, but as soon as the flow rate value exceeds such a threshold, the
meter switches on many measuring cycles again. Allowed values for this parameter: ON/OFF N.B.: to
optimise this function it is recommended choose a value for the acceleration threshold within 10÷15
(POS. 3.3)
MENU 4.ALARMS
(POS. 4.7) Current output value in case of failure [mA VAL.FAULT =% XXX]
Setting of the value the 0/4...20 mA current output has to be in one of the following cases:
empty pipe; coils interrupted; ADC error
The allowed range is from 0 to 120% of the 0..20 mA scale, 120% corresponds to 24 mA and does
not depend on the selected range (0…20 / 4…20 mA). The NAMUR NE43 recommendation asks for a
alarms signalling value for the current output lower than 3.6 mA (<18%) or bigger than 21 mA
(>105%). It would then be preferable to set the value of this function at the 10%, so that the current
value in case of the a.m. cases would be 2 mA, allowing the following diagnostics:
current < 2 mA - 5%: line interrupted, power supply failure or faulty converter;
2 mA -5% ≤ current ≤ 2 mA + 5%: hardware alarm;