Vaisala MGP261, Руководство пользователя

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7. Environmental Compensation
7.1 Overview
When necessary, environmental compensations can be applied to improve the measurement
accuracy (for example, to provide the probe with a real-time pressure reading from the
measurement environment by using input from an external sensor).
The probe can compensate for the effects of the following parameters:
• Temperature (T)
• Pressure (P)
Environmental compensation parameters can be provided to the probe from the following
sources:
• The internal temperature sensor of the probe can be used for temperature compensation.
• An external sensor can be connected to the probe (4 … 20 mA analog input, Ex ia) to
provide temperature or pressure compensation values.
• If the temperature and pressure values are known and remain constant, they can be
entered as fixed setpoint values.
• If the probe is integrated in a system that measures either temperature or pressure, they
can be updated to the probe continuously.
The method used for environmental compensation is configured on the order form when
ordering the probe, and can later be updated using Vaisala Insight PC software or Modbus
protocol.
7.1.1 Temperature Compensation
MGP261 can measure the approximate temperature of the CARBOCAP â sensor for
compensation, use a fixed setpoint value as the temperature compensation, or receive the
temperature compensation value from an external temperature sensor.
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).
7.1.2 Pressure Compensation
The probe does not have on-board pressure measurement. You can either configure a fixed
setpoint value that is used as the pressure compensation, or set the probe to receive the
pressure compensation value from an external pressure sensor.
Chapter 7 – Environmental Compensation
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