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Our means: Calibration laboratories: Hygrometry and thermometry

CALIBRATION
ACCREDITATION
N°2.21
HYGROMETRY
CALIBRATION
ACCREDITATION
N°2.1116
TEMPERATURE
CALIBRATION
ACCREDITATION
N°2.57
LIQUID FLOW RATE
MEASUREMENT
CALIBRATION
ACCREDITATION
N°2.1160
MANOMETRY

Hygrometry & Thermometry

CETIAT is accredited by COFRAC in hygrometry and thermometry for the on-site calibration. Those accreditations are on-site extensions of the national reference of the BNM-COFRAC chain as far as hygrometry is concerned, and of the calibration and thermometry laboratory for the temperature.
The calibration is performed in the test room of a humid air generator. The dew point temperature is measured with a reference hygrometer. The dry temperature measurement is performed with a reference thermometer put near the sensor to be calibrated. The reference relative humidity is calculated from those two measurements.
For underwater thermometers, the calibration is performed in a thermostatically controlled bath, by comparison with a reference platinum resistance thermometer.

TYPE OF DEVICE FIELD ENLARGED UNCERTAINTY
Dew point
temperature (Td) (Td)
Dry
temperature
Relative
humidity (RH)
Hygrometer measuring dew point -15°C
to
+68°C
- - Td ≥ ± 0,16°C
Impedance variation hygrometer (capacitive or resistive) or psychrometer 0°C to
+70°C
11% to 95% HR
± 0,3% to ±2,1%
Not immerseable probe 0°C to +70°C ≥ ±0,21°C
Industrial Platinum resistance
thermometer

-30°C
to
+200°C

≥ ±0,11°C

Thermoelectric probe ≥ ±0,15°C
Temperature measurement chain

≥ ±0,11°C

Liquid expansion thermometer ≥ ±0,14°C


Liquid flow rate measurement

The calibration is performed by making a comparison between the quantity given by the device under calibration and the indication given by a transfer reference flow meter (Coriolis mass flow meter). The stability of the temperature and of the flow pressure is checked throughout the calibration.

FIELD OF MEASUREMENT RELATIVE UNCERTAINTY
Water and aqueous solutions
Liquids other than water
Temperature : 15 - 50°C
Relative pressure : 1 to 3 bar

0.01 m3.h-1≤ qv ≤ 36 m3.h-1


from ± 7x10-3 to ± 3.3x10-2

qv : reference volume flow rate


Manometry

The calibration is performed by making a comparison between the quantity given by the device under calibration with the indication given by a transfer reference.

PRESSURE FIELD ENLARGED UNCERTAINTY
Relative and differential gas pressure
Line pressure : 1 bar
-250 to 250 Pa ±(0.5 Pa + 2.2x10-3xΔP)
-2 500 to 2 500 Pa ±(4.5 Pa + 1.5x10-3xΔP)
Gas relative pressure 0 to +20 kPa ±(8.5 Pa + 1x10-3xPr)
-95 to 200 kPa ±(20 Pa + 2x10-4xPr)
0 to 7 000 kPa ±(500 Pa + 7x10-5xPr)
Gas absolute pressure 80 to 120 kPa ±100 Pa
100 kPa to 7 100 kPa ±(500 Pa + 7x10-5xP)
 
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