THERMOMETER CALIBRATION USING CONTROLLED TEMPERATURE BATHS
THERMOMETER CALIBRATION USING CONTROLLED TEMPERATURE
BATHS
TXDOT DESIGNATION: TEX-926-K
Test Procedure for
THERMOMETER CALIBRATION USING
CONTROLLED TEMPERATURE BATHS
Texas
Department
of Transportation
TxDOT Designation: Tex-926-K
Effective Date: August 1999
1.
SCOPE
1.1
Calibrate thermometers by comparison with standard thermometers while immersed in stirred water or oil baths. Alternately, calibrate specific points by placing in a reference temperature bath such as a mixture of crushed ice and water. Make comparisons at various temperatures and record the errors. Then use correction factors when reading the thermometer. Note 1—Few thermometers are absolutely accurate. The value of errors may vary over the range of the thermometer.
Note 2—This procedure may use hot liquids and equipment that will cause burns if improperly handled. Hot oils also emit harmful vapors, so only use with proper ventilation. Most liquid-in-glass thermometers contain mercury. Mercury fumes may be hazardous if the thermometer is broken. This procedure does not address the safety problems of working with these materials. It is the responsibility of all persons performing these tests to use appropriate procedures and safety equipment.
1.2
The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard.
2.
DEFINITIONS
2.1
Bulb—A bulb is the reservoir of fluid at the lower end of a liquid-in-glass thermometer.
2.2
Calibration—Calibration is the determination of errors or differences from the true value.
2.3
Electronic Thermometer—An electronic thermometer is an electrical device that measures the change in some property of a sensor to determine the temperature. Three common sensors are Resistance Temperature Detector (RTD), Thermistor, and
BATHS
TXDOT DESIGNATION: TEX-926-K
Test Procedure for
THERMOMETER CALIBRATION USING
CONTROLLED TEMPERATURE BATHS
Texas
Department
of Transportation
TxDOT Designation: Tex-926-K
Effective Date: August 1999
1.
SCOPE
1.1
Calibrate thermometers by comparison with standard thermometers while immersed in stirred water or oil baths. Alternately, calibrate specific points by placing in a reference temperature bath such as a mixture of crushed ice and water. Make comparisons at various temperatures and record the errors. Then use correction factors when reading the thermometer. Note 1—Few thermometers are absolutely accurate. The value of errors may vary over the range of the thermometer.
Note 2—This procedure may use hot liquids and equipment that will cause burns if improperly handled. Hot oils also emit harmful vapors, so only use with proper ventilation. Most liquid-in-glass thermometers contain mercury. Mercury fumes may be hazardous if the thermometer is broken. This procedure does not address the safety problems of working with these materials. It is the responsibility of all persons performing these tests to use appropriate procedures and safety equipment.
1.2
The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard.
2.
DEFINITIONS
2.1
Bulb—A bulb is the reservoir of fluid at the lower end of a liquid-in-glass thermometer.
2.2
Calibration—Calibration is the determination of errors or differences from the true value.
2.3
Electronic Thermometer—An electronic thermometer is an electrical device that measures the change in some property of a sensor to determine the temperature. Three common sensors are Resistance Temperature Detector (RTD), Thermistor, and