Zero Cal; Auto Mode Zeroing - Teledyne 3000TA-XL-EU Operating Instructions Manual

Trace Oxygen Analyzer

4.4.1 Zero Cal

The B-2CXL cell has a zero offset of less than 0.2 ppm oxygen.
Normally, the offset slowly decreases during the first 7 to 10 days of
operation, and is expected to reach a steady value after this time.
Generally, the value of the zero offset is part of the oxygen reading
of the sample gas as shown by the analyzer readout. As an example, a
reading of 0.5 ppm oxygen may include 0.4 ppm oxygen in the sample
gas and a 0.1 ppm zero offset.
The determination of the zero offset requires the use of oxygen free
gas to the analyzer. We recommend the use of nitrogen gas with a
scrubber to assure oxygen levels below 0.02 ppm.
The user may decide to eliminate the zero offset for improved
accuracy. If so desired, the analyzer is equipped to provide this
function. However, we do not recommend carrying out the cal zero
during the first 10 days of the operation of the cell.
The Zero button on the front panel is used to enter the zero
calibration function. Zero calibration can be performed in either the
automatic or manual mode. In the automatic mode, an internal algorithm
compares consecutive readings from the sensor to determine when the
output is within the acceptable range for zero. In the manual mode, the
operator determines when the reading is within the acceptable range for
zero. Make sure the zero gas is connected to the instrument. If you get a
CELL FAILURE
message skip to Section 4.4.1.3.
4.4.1.1 A M Z
UTO ODE
Press Zero to enter the zero function mode. The screen allows you
to select whether the zero calibration is to be performed automatically or
manually. Use the ▲▼ arrow keys to toggle between
zero settling. Stop when
Press Enter to begin zeroing.
The beginning zero level is shown in the upper left corner of the
display. As the zero reading settles, the screen displays and updates
Teledyne Analytical Instruments
EROING
AUTO
appears, blinking, on the display.
Zero: Settling: AUTO
<ENT> To Begin
#### PPM Zero
Slope=####
Operation
AUTO
and
ppm/s
MAN
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