Cal, Cals, Calz, Calibration Functions - Teledyne 6200A Manual

TAI Model 6200A SO

5.2.2 CAL, CALS, CALZ, Calibration Functions

The calibration and zero/span checking of the 6200A analyzer is treated in detail in Section 7.
Table 7-1 summarizes types of calibration. The basic function of each of these keys is described
here.
5.2.2.1 CAL, CALS, CALZ
The above keys control the calibration functions of the analyzer. In the CAL mode the analyzer
can be calibrated with zero/span gas coming in through the sample input port on the rear panel. If
the analyzer is equipped with the IZS option, or Zero/Span valves, there will be CALZ and
CALS buttons also. These buttons operate the Zero/Span valves or IZS system. The setup of
these options is covered in Section 6.3, and operation is explained in Section 7.
5.2.2.2 Zero
Pressing the ZERO key along with ENTR will cause the instrument to adjust the OFFSET value
of the internal formula so that the instrument reads zero. The 6200A allows zero adjustment over
a limited range of signal levels mostly due to the background signal, therefore the signal does not
have to be exactly zero for the instrument to do a zero cal. The instrument will not, however,
allow a zero cal on any signal level, therefore it is not possible to zero the instrument with span
gas in the reaction cell. If the ZERO key does not come on as expected, check Section 9.2.9.
5.2.2.3 Span
Pressing the SPAN key along with ENTR will cause the instrument to adjust the SLOPE value of
the internal formula so the instrument displays the span value. The expected SO
concentration must be entered before doing a SPAN calibration. See Table 7-3.
Like the Zero calibration, the Span cal cannot be done with any concentration of span gas. If the
signal level is outside certain limits, the SPAN key will not be illuminated. If you encounter this
condition see Section 9.2.8. It is also possible at low levels of span concentration that both the
ZERO and SPAN keys might be on, thus allowing you to either zero or span the instrument. In
this case, care must be taken to perform the correct operation or the analyzer can become mis-
calibrated.
5.2.2.4 SO Cal Concentration
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Before the 6200A can be spanned, it is necessary to enter the expected span concentrations for
SO . This is done by using CAL-CONC. Concentration values from 50 to 19000 ppb are
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accepted. If a value of XXXX is displayed, that indicates an off scale, or invalid reading. The
XXXX value will often be displayed at power-up when there is no data yet available to be
displayed. Certain instrument fault conditions will cause X's to be displayed, this is the same as
the needle being offscale on a analog meter. See the Troubleshooting Section 9.2.8 if this occurs.
Analyzer Operator Manual, 02164, Rev. G
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