Temperature and humidity measurement errors, Temperature and humidity adjustments – Fluke 5020A User Manual

Page 128

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5020A

Users Manual

7-4

20% 25

°C

45% 25

°C

70% 25°C

Table 7-3. 5026A-H Temperature Calibration Points

Temperature

at Relative Humidity

16 °C

45%

20 °C

45%

24 °C

45%

Table 7-4. 5026A-H Relative Humidity Calibration Points

Relative Humidity

at Temperature

20% 20

°C

45% 20

°C

70% 20

°C

Temperature and Humidity Measurement Errors

The temperature and humidity measurement errors for the sensor are obtained at each of

the calibration points. This test is performed to obtain as found data for the calibration

report, if necessary, and adjustment data, and then repeated after adjustments are made to

obtain as left data for the calibration report. Temperature measurements are in degrees

Celsius. For each calibration point Tn and RHn, do the following:

1. Set the temperature and humidity set-point.
2. Allow four hours for settling after the temperature and humidity set-points are

reached before collecting data.

3. Measure the temperature with the 5026A-x probe and compare it with the

temperature read from the reference thermometer in the chamber to obtain the

temperature measurement error:

)

(

)

(

2626

)

(

Tn

Treference

Tn

x

T

Tn

Terror

=

or
Measure the relative humidity using the 5026A-x probe and compare it with the

relative humidity read from the chamber to obtain the humidity measurement

error:

)

(

)

(

2626

)

(

RHn

RHchamber

RHn

x

RH

RHn

RHerror

=

Temperature and Humidity Adjustments

Adjustments to the 5026A-x calibration parameters are required when measurement

errors are excessive or outside of the specification. The calibration parameters can be

accessed using the SENSOR CAL function in the CHANNEL menu. The password is

required to change the parameters. Calculation of new calibration parameters requires

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