Contrec 515, Руководство по эксплуатации

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Instrument Calibration
515 HC04 - 8 June 2007 35
Inputs
↓ →
UNITS PARAMS
INPUTS
OUTPUTS ALARMS COMMS TM/LOG SETUP TEST END
INPUT
DIF-PR AINP3
AINP4
For this application, Analog Input Channel 3 is assigned to differential
pressure main input (if not stacked) or low range input if stacked with
Analog Input Channel 4.
TYPE AINP3
AINP4
Select the type of analog input source.
Press or to select 0-5V, 1-5V or 4-20mA.
PT-MIN AINP3
PT-MAX AINP4
Enter the value of the measured parameter (in the assigned engineering
units) that corresponds to the minimum input signal level. The minimum
point is commonly set at a base flowrate of 0.0.
Enter the value of the measured parameter (in the assigned engineering
units) that corresponds to the maximum input signal level. The maximum
point is the same as the base value (set at the minimum point) plus the
span value.
For example, if the source signal is 4mA at a minimum differential
pressure of 0kPa, enter 0 as the minimum point. If the source signal is
20mA at a maximum differential pressure of 200kPa, enter 200 as the
maximum point.
CUTOFF AINP3
AINP4
The Cut-off is the lowest value that the instrument reads from the input
sensor. The cut-off setting is the percentage of the span of the input
values.
All inputs at or below the cut-off value are considered negligible to the
instrument and are ignored. In this case, the instrument uses the minimum
value (set at PT-MIN).
FILTER AINP3
AINP4
Input fluctuations caused by pulsating flow tend to create distortion in the
input readings of the rate. The instrument has a digital filter that averages
out these fluctuations.
As a guide to the degree of filtering to use, the following table shows the
response time (in seconds) to reach 90% and 99% of a step change in
input.
The value A is the filter constant that the user can set.
SET