14
Offset adjustment is done at a potentiometer on the circuit board within
an adjustment range of ± 10 % of the device’s pressure range.
Ex-factory this potentiometer is in center position and is lacquer sealed.
All settings and adjustments that are made before must be done in this
configuration.
Offset adjustment is carried out using a tool called “screwdriver 2.5”
(blade with in mm).
Automatic offset setting
1. Before setting the zero point, the device must be in operation for
at least 60 minutes.
2. Connect pressure inputs P (+) and P (–) by means of a hose
(pressure difference between both inputs = 0 Pa).
3. For zero point setting press button uninterruptedly for 5 seconds.
A LED signalises prompting the calibration by short flashing,
and after a short countdown the measured (current) offset value is
added to the measurand and zero voltage safe stored.
Correct calibration is confirmed by steady light of the LED for
3 seconds respectively indicated in the display (optional) by switching
from “AUTO 0” to “PROG 0”.
Note: By releasing the button during the countdown (counter > 0),
zero point setting is immediately terminated!
Manual offset adjustment
At the potentiometer OFFSET ∆P can be balanced.
The adjustment range is ca. ± 10 % of the pressure range.
Here another reference point different from zero point can be used.
Readout in the display
In the 1st line of the display, the ACTUAL pressure up to the measuring range
limit is displayed.
Switching between the units Pa and hPa (100 Pa = 1 hP) happens automatically.
Pa = Pascal
hP = Hektopascal
The following configurations can be preset via
DIP switches.
The DIP switch sliding blocks can be moved
without using tools. DIP switch 6 is not assigned.
Pressure ranges
In each case four different pressure ranges
depending on the type of device can be preset
via DIP switches DIP 1 and DIP 2.
Measuring range mode
The measuring range is configured via DIP
switch DIP 3, either into the unidirectional range
or into the bidirectional range.
Therefore altogether eight pressure measuring
ranges are configurable.
Characteristic line – analog output
The output characteristic line can be defined via
DIP switch DIP 4. Here is distinguished between
a linear and a square root extracting output
characteristic line. When square root extracting
output characteristic line is selected, the
measuring range setting at DIP switches DIP 1
and DIP 2 is without function.
In that case the maximum pressure range is
used for computation.
Measurement signal filtering
In order to stabilize the pressure measurement
signal and the output voltage, the measurement
signal is filtered.
The time interval for such averaging can be
preset via DIP switch DIP 5 to 1 or 10 seconds.
By a longer filtering interval, the settling time of
the sensor is automatically extended.
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PREMASGARD
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111x ⁄ 112x ⁄ 112x - SD
| Configuration and zero point calibration
