Teledyne LXT-280 - Manual (Page 29)

Dissolved Oxygen Transmitter Calibration
Teledyne Analytical Instruments 19
Calibration
4.1 Calibration
A complete calibration of the LXT-280 Dissolved Oxygen
transmitter involves:
1. Zero calibration
2. Span calibration
3. Output calibration
4. DO Locus calibration
5. Temperature calibration (trim)
In general, once the instrument has been setup, only step 2 will be
required for calibration although it is recommended that the output and
temperature calibration be occasional rechecked and adjusted as
necessary. It is also highly recommended that you perform a zero
calibration (step 1) periodically to check for drift and whenever a new
sensor is installed.
It may be useful to set the contrast of the display prior to calibration
to compensate for current lighting conditions.
Note: Before calibrating the LXT-280, place the instrument in
Manual Mode. See the following section.
4.2 Manual Output Mode
In order to perform calibrations without interfering with control or
recorder functions, the LXT-280 incorporates a manual output mode. In
the manual output mode, the current output is set to the desired level and
saved until changed or released from the manual mode. The following
procedure demonstrates the use of the manual output.
Procedure:
1. If not at the Main Menu, magnetically activate the appropriate
VERTICAL ▲/▼ arrow key.