Teledyne 6200E - Sulfides Analyzer - Manual (Page 71)

Model 6200E Instruction Manual Operating Instructions
M6200E Rev: A1 71
NOTE
On analyzers with the SO
2
-H
2
S multigas measurement option installed (see section 5.5)
the outputs of A1 and A2 correspond to:
Output SO
2
SO
2
– H
2
S H
2
S
Channel Mode Mode Mode
A1 ÅÆ SO
2
ÅÆ SO
2
ÅÆ H
2
S
A2 ÅÆ SO
2
ÅÆ H
2
S ÅÆ H
2
S
As the instrument switches from H
2
S mode to SO
2
mode and back, only the reporting
range and analog output associated with the gas currently being measured will be active.
The reporting range and analog output for the gas no being measured will continue to
report the last valid reading.
The output, labeled A4 is special. It can be set by the user (see Section 6.9.10) to output many of
the parameters accessible through the <TST TST> keys of the units Sample Display.
Output A3 is not available on the Model 6200E Analyzer.
6.7.2. Physical Range versus Analog Output Reporting Ranges
The M6200E UV Fluorescence H
2
S Analyzer has two hardware physical ranges that cover H
2
S
concentrations between 0 and 20,000 ppb. The low range is 0 to 2,000 ppb, while the high range is
0 to 20,000 ppb. The proper physical range is determined by the software to include the maximum
measurement concentration selected by the user. Once properly calibrated, the analyzer’s front
panel will accurately report concentrations along the entire span of its 0 and 20,000 ppb physical
range.
Because, most applications use only a small part of the analyzer’s two physical ranges, the width of
the Model 6200E’s physical range can create data resolution problems for most analog recording
devices. For example, in an application where the expected concentration of SO
x
is typically less
than 500 ppb, the full scale of expected values is only 0.25% of the instrument’s 20,000 ppb
physical range. Unmodified, the corresponding output signal would also be recorded across only
0.25% of the range of the recording device.
The M6200E solves this problem by allowing the user to select a scaled reporting range for the
analog outputs that only includes that portion of the physical range relevant to the specific
application. Only the reporting range of the analog outputs is scaled, the physical range of the
analyzer and the readings displayed on the front panel remain unaltered.
6.7.3. Reporting Range Modes
The M6200E provides three analog output range modes to choose from. The actual signals output
on the two analog signal channels depends on whether or not the analyzer includes a SO
2
/H
2
S
multigas measurement option and if so which measurement mode is selected.