Baker Hughes Panametrics Aurora H2O, User Manual

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The user calibration menu
is now enabled.
The selections on the user calibration menu include the
following functions:
Item Purpose
Zero gas
User specifies the water concentration, in
PPMv, of the “zero”, or dry gas
Span gas
User specifies the water concentration, in
PPMv, of the “span”, or cal/wet gas
Read zero
The Aurora H2O will read the signal while
exposed to the zero gas.
Read span
The Aurora H2O will read the signal while
exposed to the span gas, then determine the
CH4 offset and scalar calibration values.
CH4 offset
Permits the user to view/edit the calculated
offset term.
CH4 scalar
Permits the user to view/edit the calculated
scalar (gain) term.
First select the zero gas
and span gas items, to
specify the cal gases to
be used. The zero gas
must be in the range of
0.0 to 50.0 PPMv water.
It is recommended that
the zero gas be 10.0
PPMv or higher for best
results. The span gas
must be in the range of
0.0 to 5000.0 PPMv water.
It is recommended that
the span gas be 500.0
PPMv or lower for best
performance.
Apply the zero gas, and
wait for the Aurora H2O
reading to stabilize.
NOTE: The user can exit to
the display and return to
the user cal menu without
affecting the calibration
procedure.
When the reading is
stable, select read zero.
The Aurora H2O performs
multiple measurements
for approximately 15
seconds, indicating
its progress. When the
readings are complete,
you will be prompted to
apply the span gas, and
continue. If there is doubt
about the stability of the
zero gas, the reading can
be repeated at this point.
Apply the span gas, and wait for the Aurora H2O reading
to stabilize.
When the reading is stable, select read span. The
Aurora H2O
uses the current measurement, and immediately calculates
the new calibration. If the calculated values are determined
to be valid, the Aurora H2O will display “calibration ok” and
prompt you to save the results, or cancel. If the values are
not valid, the Aurora will display “calibration *FAILED*”, and
prompt you to continue. On a cal failure or cancel, no change
is made to the user calibration values.
The CH4 offset and CH4
scalar items can be used
to view or modify the
calculated calibration
points, if desired.
NOTE: The default values for the CH4 offset is 0.0 and the
CH4 scalar is 1.0. These defaults are NOT the same as the
factory calibration! Making the user cal active without
performing the actual calibration will adversely affect the
accuracy of the Aurora H2O . If there is any doubt about the
quality/accuracy of the gases used, the Aurora H2O should
be returned to the factory calibration using the status item.
4.8 Service settings
CAUTION!
The service settings menu should be used by
factory-trained personnel only.
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