Fluke Hart Scientific 1575 Super-Thermometer, Руководство пользователя

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4. Enter the CAL ITS-90 function and use SETUP. You must specify that
you want to calibrate the probe by selecting a channel for it (see Section
7.4.4.2.6). Since you will not actually be measuring the data, you may
select any arbitrary channel as long as the probe is not set to NO CAL.
You may ignore the other setup parameters since they pertain only to the
measurement process.
5. Enter the DATA function in CAL ITS-90. Select your probe number. En-
ter the resistances (from Step 2) and temperatures for each calibration
point (see Section 7.4.4.2.8). For the water triple point, enter the same
resistance that was used to calculate the resistances in Step 2.
6. Now you are ready to calculate coefficients. Enter the CALCULATE
function. Select your probe number and press CALCULATE (see Sec-
tion 7.4.4.2.9).
7.4.4.2.6 Setup
The SETUP function is used to select options for the calibration process. Be-
fore beginning the setup, you must properly set up the probe definitions for
each probe to be calibrated as well as the reference SPRT. You should set the
serial number, conversion (ITS-90), reference resistor, current, and subranges.
For the probe that will be used as the reference SPRT, you must also enter the
correct characterization coefficients. Use the EDIT PROBE function in the
PROBE MENU to set these parameters. Also, make sure that the sample timing
and digital filter parameters are set appropriately in the SAMPLE MENU. To
remind you that the probe parameters must be set before beginning the calibra-
tion, a message appears when you begin SETUP. Press the NEXT soft-key (also
Enter or Exit) to continue.
The setup parameters are grouped in four screens. The first screen sets up the
temperature reference. You must specify the type of reference. If only fixed
points will be used, select FIXED POINTS. If an SPRT will be used to measure
the temperature at any or all of the points, select the probe number of the refer-
ence SPRT.
If an SPRT was selected as the temperature reference, specify the channel to
use with the SPRT. It is often most convenient to use Input 2 unless the SPRT
or other probes will be using an external reference resistor.
Note: For an SPRT
resistance comparison type calibration, you must select Input 2 for the refer-
ence SPRT. Press the NEXT soft-key (or Exit) to continue.
The next screen selects the calibration probes and their channels. For each
probe to be calibrated, select the channel to use. If the 2590 scanner is con-
nected to the 1575/1590 Thermometer, the channels SCANNER 1 through
SCANNER 10 will also be available along with INPUT 1 and INPUT 2. Do not
choose INPUT 2 for any probe set up to use an external reference resistor. Se-
lect NO CAL for all probe numbers that will not be used. You will not be al-
lowed to set the channel for a probe number that is designated as the reference
SPRT or one that does not have the conversion set to ITS-90 with a valid
subrange. Press the NEXT soft-key (or Exit) to continue.
59
7 Front Panel Operation
Probe Menu