Fluke 9140 Dry-well Calibrator - Manual (Page 34)

7.6 Controller Configuration
The controller has a number of configuration and operating options and calibra-
tion parameters which are programmable via the front panel. These are ac-
cessed from the secondary menu after the proportional band function by
pressing “SET”. Pressing “SET” again enters the first of three sets of configu-
ration parameters — calibration parameters, operating parameters and serial in-
terface parameters. The menus are selected using the “UP” and “DOWN” keys
and then pressing “SET”.
7.6.1 Calibration Parameters
The operator of the instrument controller has access to a number of the calibra-
tion constants namely R0, ALPHA, and DELTA. These values are set at the
factory and must not be altered. The correct values are important to the accu-
racy and proper and safe operation of the instrument. Access to these parame-
ters is available to the user so that in the event that the controller memory fails
the user may restore these values to the factory settings. The user should have a
list of these constants and their settings with the instrument manual.
CAUTION: DO NOT change the values of the instrument calibration con-
stants from the factory set values. The correct setting of these parameters
is important to the safety and proper operation of the instrument.
The calibration parameters menu is indicated by,
CAL Calibration parameters menu
Press “SET” five times to enter the menu. The calibration parameters menu
contains the parameters, R
0
, ALPHA, and DELTA, which characterize the re-
sistance-temperature relationship of the platinum control sensor. These parame-
ters may be adjusted to improve the accuracy of the calibrator. This procedure
is explained in detail in Section 10, Calibration Procedure.
The calibration parameters are accessed by pressing “SET” after the name of
the parameter is displayed. The value of the parameter may be changed using
the “UP” and “DOWN” buttons. After the desired value is reached press “SET”
to set the parameter to the new value. Pressing “EXIT” causes the parameter to
be skipped ignoring any changes that may have been made.
7.6.1.1 R0
This probe parameter refers to the resistance of the control probe at 0°C. The
value of this parameter is set at the factory for best instrument accuracy.
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7 Controller Operation
Controller Configuration