Instruction manual

NGA 2000 HFID
Instruction Manual
HAS64E-IM-HW
September 2008
3 - 8 Operation Emerson Process Management GmbH & Co.OHG
Span Adjustment
After that, perform a Span adjust in the same measur-
ing range:
Supply heated span gas to sample input. The reading
of the sample pressure, oven, and sample temperatures
should be the same as that used during the adjustment
of the zero gas.
For that, push the F4 softkey in the Basic Controls menu,
so that the Analyzer Span menu turns up:
Figure 3-9: Analyzer Span Menu
Push the softkey F4 again to start the spanning se-
quence. Be sure to have span gas flowing through your
analyzer and to have it purged before.
When the spanning sequence is finished, the "Calibra-
tion status" will turn to "READY".
If the user is unable to calibrate the Analyzer Module
(i.e., when ZERO or SPAN is initiated, nothing happens),
several possible solutions present themselves. One
solution relates to the use of an incorrect gas for zero-
ing or spanning (e.g., using a high concentration gas to
zero or a zero gas to span the Analyzer Module). Sim-
ply recalibrating with the appropriate gas(es) will not
correct the problem because the ZERO OFFSET or
SPAN FACTOR has been set to an extreme value in the
process.
c) Problems with Calibration
If the user is unable to calibrate the Analyzer Module
(i.e., when ZERO or SPAN is initiated, nothing happens),
several possible solutions present themselves. One
solution relates to the use of an incorrect gas for zero-
ing or spanning (e.g., using a high concentration gas to
zero or a zero gas to span the Analyzer Module). Sim-
ply recalibrating with the appropriate gas(es) will not
correct the problem because the ZERO OFFSET or
SPAN FACTOR has been set to an extreme value in the
process.
To remedy the problem, do the following:
1. Verify the correct zero and span calibration gases
are being used properly. If so, attempt to recalibrate
according to instructions at the beginning of Sec-
tion 3-4, ensuring that the oven, sample and case
temperatures and displayed measurement read-
ing are stable before initiating the calibration rou-
tine. If incorrect gases were used in the initial, failed
calibration, skip to step 2.
2. Disable Calibration Adjustment Limits
(Figure 3-5).
3. Recalibrate the analyzer module according to in-
structions at the beginning of section 3-4, ensur-
ing that oven, sample, and case temperatures and
displayed measurement reading are stable before
initiating the calibration routine.
4. Enable Calibration Adjustment Limits in the Cali-
bration Parameters menu (Figure 3-5).
NOTE
If the range selections straddle 72 5ppm, CH
4
, the
zero and span calibration for each range must be
done separately.
Line#1
HOME ESCAPE INFO
0.000 ppm
SPAN
Analyzer Span
Are you sure ?
You must have span gas flowing through the analyzer.
Calibration time:
Measurement range number:
Span ranges:
Calibration status:
Error message for last span:
24 s
1
SEPARATELY
READY
CAL OK