2.8 Environmental Compensation for Pressure
When necessary, you can apply pressure compensation to improve the measurement accuracy
of the probe (probe software v.1.1.0 and later). The probe does not have on-board pressure
measurement, but a pressure reading from an external source can be used as a setpoint value
for compensation.
You can configure the pressure compensation parameters using Vaisala Insight software,
Modbus configuration registers, or an Indigo 200 transmitter.
By default, the pressure compensation is turned o. When the compensation is o, the probe
uses the default compensation value (1013.25 hPa).
Pressure compensation
aects the following parameters:
• H
2
O
2
concentration (ppm)
• H
2
O concentration (ppm)
• Relative saturation (%RS)
More Information
‣
Vaisala Insight Software (page 28)
‣
Configuration Registers (page 48)
2.9
Measurement Filtering Factor
You can set a filtering factor that aects the speed at which the latest H
2
O
2
and RS
measurements are integrated into the output of the probe. This allows averaging the output if
the measuring environment produces occasional exceptionally high or low readings.
The
filtering factor can be set either with Modbus configuration register 0308
hex
, Vaisala
Insight software, or an Indigo 200 transmitter.
By default, the
filtering factor is set to 1.0, which means the latest measurement is shown
directly in the output, without any filtering. To apply filtering, enter a lower filtering factor to
include previous measurements in the calculation of measurement output. For example,
changing the
filtering factor to 0.9 results in an output that is a combination of the latest
measurement (90%) and the previous measurement output (10%).
More Information
‣
Configuration Registers (page 48)
2.10
Connectivity to Vaisala Insight Software
The probe can be connected to Vaisala Insight software using a Vaisala USB cable (no.
242659). With the Insight software, you can:
• See device information and status.
HPP272 User Guide M211972EN-B
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