Vaisala GMP252 - Temperature Compensation

Compensation parameters are configured on the order form when ordering the probe, and
can later be updated using Vaisala Industrial Protocol or Modbus protocol.
You can also turn o any of the compensations. In that case, the probe uses the default
compensation value that is mathematically neutral for the probe’s internal compensation
model.
You can configure the environmental compensation settings with any of the following
options:
• Vaisala Industrial Protocol serial commands
• Vaisala Insight software
• Indigo transmitter's wireless
configuration interface
• Modbus configuration registers
• MI70 hand-held indicator
The environmental compensation
configuration options available in the MI70 handheld
indicator are not compatible with the probe. Using MI70 to configure the environmental
compensation settings of the probe can decrease measurement accuracy.
More Information
‣
Eect of Environmental Compensations (page 95)
‣
Environmental Compensation Commands (page 52)
‣
Vaisala Insight Software (page 61)
‣
Changing Environmental Compensation Settings with Indigo (page 76)
‣
Configuration Registers (page 114)
‣
Changing Environmental Compensation Settings with MI70 Indicator (page 88)
2.4.1
Temperature Compensation
The probe can measure the approximate temperature of the CARBOCAPâ sensor for
compensation, or use a
fixed setpoint. Unless a dedicated temperature measurement is
available and can be regularly updated to the probe, it is strongly recommended to use the
probe's internal temperature compensation to ensure real-time accurate measurements. If
the measurement is made in a constant temperature, the constant temperature can be set as
the compensation value
(fixed setpoint option).
If temperature compensation is turned o, the probe uses the default value of +25 °C
(+77 °F).
When the probe is installed through a
flange and part of the probe and the cable is left
outside the measuring environment, it is possible that temperature conduction from the
probe body and cable outside the measurement environment aects the temperature
compensation and decreases measurement accuracy.
GMP252 User Guide M211897EN-D
16