Teledyne 6200E - Sulfides Analyzer - Manual (Page 184)

EPA Protocol Calibration Model 6200E Instruction Manual
184 M6200E Rev: A1
8.3. ZERO and SPAN Checks
A system of Level 1 and Level 2 zero span checks (see Table 8-4) is recommended. These checks
must be conducted in accordance with the specific guidance given in Subsection 9.1 of Section
2.0.9 (Q.A. Handbook). It is recommended Level 1 zero and span checks conducted every two
weeks. Level 2 checks should be conducted in between the Level 1 checks at a frequency desired
by the user. Span concentrations for both levels should be between 70 and 90% of the
measurement range.
Zero and span data are to be used to:
• Provide data to allow analyzer adjustment for zero and span drift;
• Provide a decision point on when to calibrate the analyzer;
• Provide a decision point on invalidation of monitoring data.
Items 1 and 2 are described in detail in Subsection 9.1.3 of Section 2.0.9 (Q.A. Handbook). Item 3
is described in Subsection 9.1.4 of the same section.
Refer to the Troubleshooting Chapter 11 of this manual if the instrument is not within the allowed
variations.
8.3.1. Zero/Span Check Procedures
The Zero and Span calibration can be checked a variety of different ways. They include:
Manual Zero/Span Check - Zero and Span can be checked from the front panel keyboard. Follow
the procedures described in Section 7.3 and 7-6 of this manual using calibrated SO
2
span gas (see
Table 7-1) only.
Automatic Zero/Span Checks - After the appropriate setup, Z/S checks can be performed
automatically every night. Follow the procedure described in Section 7.9 of this manual using
calibrated SO
2
span gas (see Table 7-1).
Zero/Span checks via remote contact closure = Zero/Span checks can be initiated via remote
contact closures on the rear panel. Follow the procedures described Section 7.7.1 of this manual
using calibrated SO
2
span gas (see Table 7-1).
Zero/Span via RS-232 port - Z/S checks can be controlled via the RS-232 port. See Section6.12.2
and Appendix A-6 of this manual for more details.
8.4. Precisions Calibration Procedures and Checks
Calibration must be performed with a calibrator that meets all conditions specified in Subsection
2.9.2 (Q.A. Handbook). The user should be sure that all flow meters are calibrated under the
conditions of use against a reliable standard. All volumetric flow rates should be corrected to 25 o C
(77 o F) and 760mm (29.92in) Hg. Make sure the calibration system can supply the range of the
concentration at a sufficient flow over the whole range of concentration that will be encountered
during calibration.