Burkert SE 56 Manuel D'instructions page 30

(POS. 3.4) Peak cut off threshold
Anomalous signal peak 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
transmitter 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 sample will
be accepted and processed as it is by the transmitter.
(POS. 3.7) Automatic scale change enable/disable
Enables the automatic change of scale. The transmitter 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 transmitter 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
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 transmitter 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
transmitter goes on with "off" cycles, but as soon as the flow rate value exceeds such a threshold, the
transmitter switches on many measuring cycles again. Allowed values for this parameter: ON/OFF
N.B.: to optimise this function it is recommended to choose a value for the acceleration threshold
within 10÷15 (POS. 3.3)
(POS. 4.7) Current output value in case of failure
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 an
alarm 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 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 transmitter;
2 mA -5% ≤ current ≤ 2 mA + 5%: hardware alarm;
4 mA ≤ current ≤ 20 mA: normal working range;
20 mA < current ≤ 22 mA: out of range, measure above 100% f.s.
MENU 4.ALARMS
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SE 56
[PEAK THR=% XXX]
[AUTORANGE=ON/OFF]
[E.SAVING=ON/OFF]
[mA VAL.FAULT =% XXX]