Hach Ultra ORBISPHERE 510, Operator'S Manual

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Orbisphere 510/511/512 Analyzers - Calibration Menu 65 of 138
Operator Manual
ORBISPHERE
5.8 External Pressure Calibration (optional sensor)
Two calibration methods for the external pressure sensor
can be selected:
• Two point calibration (recommended)
• One point calibration
By default the two point calibration is selected
Fig 5-3:
Two Point Calibration
Two Point Calibration (recommended)
Connect a certified absolute pressure gauge to the
sample line, and use a certified precision barometer.
• The two point calibration starts with barometric
pressure for the lower point. Expose the external
pressure sensor to the atmosphere.
Enter the barometric pressure read on the
barometer in the upper window and
validate P1
.
• Expose the external pressure sensor to line
pressure, making sure it is exposed to the same
pressure as the certified absolute pressure gauge.
Enter the absolute pressure value read on the
certified absolute pressure gauge in the lower box,
and
validate P2
.
Note:
Any pressure can be used for P1 and P2, but for an
accurate calibration P1 and P2 should be as different as
possible.
Fig 5-4:
One Point Calibration
One Point Calibration
Connect a certified absolute pressure gauge to the
sample line.
See “Generic Terms and Definitions” on
page 132
• Expose the external pressure sensor to the line
pressure, making sure it is exposed to the same
pressure as the certified absolute pressure gauge.
Enter the absolute pressure value read on the
certified absolute pressure gauge in lower box, and
validate P1
.
Note:
Any pressure can be used for P1, but for one point it
should be as close as possible to the sample pressure