FISCHER Mess- und Regltechnik GmbH
Commissioning | 3
BA_EN_MS13
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NOTICE
Adjustment of the output signal
The basic measuring range (indicated on the type label) and the type of output
signal (voltage / current) are not variable.
The parameters
MB start
and
MB end
initially define the two pressures
between which the output signal will change at all. Both values are adjustable
across the entire basic measuring range. The set values also refer to the pres-
sure in the respective unit. However, the signal values (current / voltage) for
‘Start of measuring range’ and ‘End of measuring range’ are fixed.
If
MB start
is smaller than
MB end
, this is called an increasing characteristic
curve; the output signal increases as the pressure increases.
If
MB end
is smaller than
MB start
, this is a decreasing characteristic curve and
the output signal decreases as the pressure increases.
The difference between the values
MB start
and
MB end
must be at least 25 %
of the basic measuring range.
You can select a unit other than the unit of the basic measuring range with the
parameter
Unit
. The user should remember however that not every unit is suit-
able. The conversion is automatic.
The parameter
Limit
allows the display, output and switching points to be lim-
ited to the range between Start of measuring range and End of measuring
range. This makes sense when content is measured to avoid "negative con-
tents". If Limit is set to "no", those measured values that are greater or smaller
than the end values are shown.
3.3.4 Menu Level Output
Parameter name
Description
Value range
min. output
min. output
0.0 … 21.0 mA or
0.0 … 11.0 V
max. output
max. output
Error signal
Measuring range unit
The parameters
min. output
,
max. output
and
error signal
define the limits of
the output signal that may not be undercut or exceeded regardless of the pres-
sure. The limit values take priority over the range defined by the
MB start
and
MB end
parameters! These parameters primarily serve to prevent error mes-
sages in downstream systems caused by brief overstepping of measuring
ranges.
The parameter
min. output
is usually only used for devices with an output sig-
nal 4…20 mA because frequently values of below 3.8 mA are evaluated as er-
ror signals.
The
max. output
value can be used for the voltage and current to limit the max-
imum value.
The value defined via the parameter
Error signal
is issued if the device detects
an internal error and can no longer work correctly. It should be noted here that
not all potential errors and faults can be detected by the device itself.