Ashcroft ATE-100 Handheld LCD Digital Calibrator - Manual (Page 54)

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Revision 4.6 3/2004
The HHC will respond by prompting the operator to
enter the number of “as found” data points to be taken.
A data point consists of the pressure measurement as
read on the calibrator and the current or voltage output
from the device under test as measured on the calibrator.
Therefore, each data point is actually two (2) measure-
ment values. The prompt appears as follows.
Enter#of Testpts
.000000
The number of test points can be any value from 1 to 21.
Important Note: The HHC can store sufficient mea-
surement data to calibrate 10 devices each with 10 “as
found” and 10 “as left” data points (corresponding to
200 test points. Each test point includes both pressure/
temperature and electrical measurement data). In addi-
tion to storing the measurement test data the heading or
label information for each calibration is also stored in
memory. This information includes: tag name, ambient
temperature, “as found” label, “as left” label and action
taken.
Prior to initiating the calibration process the base unit
will prompt the operator with a screen providing the
remaining storage capacity for data in terms of number
of data points. If the operator enters a number of test
points that exceeds the available memory the following
message will be displayed:
Value exceeds #
remaining points
Pressing any key will return the prompt requesting entry
of the number of test points to be run. The number of
test points entered must be less than or equal to the
remaining test points available. Memory requirement for
the calibration heading information are already factored
into the information provided regarding the number of
test points remaining. The number displayed may be
completely allocated to measurement data without worry
about leaving space for needed labelling.
Step 8 Using the numeral keys enter the desired
number of “as found” data points to be logged. In this
example 10 data sets will be stored in the calibrator’s
data logging memory.
Enter#of Testpts
10
Step 9 With the desired number of test points entered
and displayed press the enter key.
ENT
The HHC will respond by returning basic measurement
operation.
Step 10 Prior to beginning the collection of data the
HHC should be set up to display the information to be
logged in the HHC’s memory. For example, in standard
transmitter calibration the calibrator display will rou-
tinely display the measured value from the Quick Select
pressure module being used as the pressure standard
and the measured current (mA) value output from the
transmitter (input to the mA and COMM jacks on the
calibrator front panel) as a result of the pressure input
applied to the transmitter.
Therefore the HHC will typically be displaying either of
the two following sets of information when performing
the calibration process.
mA PSI
xxxxx yyyy
or
PSI mA
yyyy xxxxx
where: yyyy= the pressure measurement value
xxxx= the current measurement value
(output from the device under test)
Step 11 With the data to be logged shown on the dis-
play, introduce the first pressure/temperature measure-
ment to be logged. After the system has stabilized press
the data store key.
DATA
STORE
The HHC will briefly show the following information
on the display each time a measurement set is logged
to memory.
xx yy%
1234 1234
where:
xx = the number of data points (records) and data
fields used for calibration labelling information
stored in
this calibration data set.
yy = the percent of data logging memory allocated to
stored data.
1234 = the measured values in the engineering units
chosen.
Step 12 Repeat the process, subjecting the HHC
and the device under test to the controlled pressure/
temperature input for each test point to be taken and
store the measured values by pressing the data store key
for each measurement set to be logged.