Thermo Neslab RTE 140, Instruction And Operation Manual

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Calibration Calibration Calibration Calibration Calibration
The microprocessor controller has three different modes of calibration: Self-
Cal, Two-point, and One-point. The controller is shipped from the factory with
a Two-point calibration so no additional controller calibration may be re-
quired. Both the internal probe and the remote sensor input must be indepen-
dently calibrated. Different calibration modes for each probe can be used if
desired. The remote sensor input has been Self-Calibrated at the factory.
Self-Cal is used to initialize the analog-to-digital (A/D) converter input chan-
nel before performing the other types of calibrations. This mode removes all
previous calibrations and brings the measurement error to less than 2°C. If
this is the required accuracy, then no additional calibration is needed.
Two-point calibration is used to negate A/D and probe errors over the full
span of the controller. This type of calibration is performed when high
accuracy is desired.
One-point calibration (offset) is used to make the controller very accurate at
one specific operating temperature.
One-point Calibration can be performed after a Two-point calibration as
many times as desired. Each One-point calibration adds a different offset to
the original Two-point calibration data (if one was already performed).
Calibration Procedures Calibration Procedures Calibration Procedures Calibration Procedures Calibration Procedures
Note: Note: Note: Note: Note: The controller should be powered at least 15 minutes before calibra-
tion to assure the electronic circuits are at operating temperature. To perform
One and Two-point calibrations on the remote sensor input the unit must be
in the remote sensor mode. Messages will end with CAL 1 for internal probe
calibrations and CAL 2 for remote sensor calibrations.
Self-Cal: Self-Cal: Self-Cal: Self-Cal: Self-Cal: The controller must be deactivated (displaying OFF) to access this
mode. Press SETPT followed by ENTER to Self-Cal the internal probe input.
The message “S-CAL 1” will be followed by “done”. To Self-CAL the sensor
input press SENSOR followed by ENTER. The message “S-CAL 2” followed
by “done” will be displayed.