Series PD-39 with mPm plug
Series PD-39 with Binder plug
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For applications where the differential pressure range is between
5% and 100% of the maximum line pressure, recent advances in micro-processor
based compensation techniques now offer distinct advantages by using
two absolute sensors, instead of conventional methods.
The Series PD-39 uses the PlC 1400 micro-processor, to compare the
signals from two absolute sensors with a resolution of 10000 points
or 0,01%. The micro-processor analyses inputs from a temperature
sensor built into the piezoresistive chip and the raw input from
the pressure sensor. Both of these inputs are corrected using mathematical
modelling techniques and polynomial equations, which are programmed
into the EEPROM by the automated calibration test equipment. In
effect, this eliminates all repeatable errors due to temperature
coefficients and non-linearity of the basic sensors. The signal
from the two absolute sensors is then compared and the differential
value is fed into a 15 bit DIA which converts the information into
an analog output signal of 4.20 mA or 0.. .10 V. The output updates
at a rate of 50 measurements per second.
Digitally corrected pressure transmitters offer the user the elimination
of nearly all repeatable errors. This inevitably means the way,
in which the "accuracy" of such a device is quoted, is radically
improved when compared with traditional analog instruments. Parameters
such as non-linearity, thermal coefficients, line pressure zero
shift, and end points are no longer relevant. The new term, Total
Accuracy (TA), includes all repeatable errors over the compensated
temperature range.
Get the data sheet
Note: data sheets are in Adobe Acrobat (.pdf) format
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