Teledyne Analytical Instruments LXT-380, Instructions Manual

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Calibration LXT-380 Universal Transmitter
Teledyne Analytical Instruments
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4.0.2 STANDARDIZE CALIBRATION DESCRIPTION
A Standardize Calibration is a single point calibration where the
transmitter’s reading is adjusted to agree with a solution of known value,
either a calibration standard, a grab sample or laboratory
determined value. In many cases the constituents and the
pressure and temperature of the process solution are very
different from the calibration solution. In these cases, once
the sensor has equilibrated, the Zero Point or Offset value
may have shifted from the original calibration point.
Standardization allows for correction of this type of offset.
When the STAND key is pressed, the user is prompted to ENTER
VALUE. The user enters the value they want the transmitter to read and
press OK. The user is then prompted to accept the value, yes/no, and the
calibration is complete. Standardizations are single point calibrations.
At the end of each calibration the Offset and Slope are displayed in
the respective units, pH, mV, ppm, mg/l.
4.0.3 MANUAL CALIBRATION DESCRIPTION
Manual calibration allows the user to enter calibration
data for an electrode into the transmitter without
performing a calibration. A MANUAL Calibration requires
the entry of three pieces of data, (1) A concentration with
the (2) corresponding mV value and (3) a slope for the
electrode. This allows laboratory generated calibration data
for an electrode to be entered in a remote analyzer where
calibration is difficult or impractical.
Example: MANUAL Calibration for a pH electrode:
1.
Calibrate the pH electrode in the laboratory.
2. Record the mV value of some pH Standard, pH
7.00 buffer = 6.8 mV (any pH – mV pair will
work).
3. Calculate and Record the slope of the electrode,
58.2 mV/pH.
4. Install the electrode into the field mounted