API MPMS 7.2:1995 pdf download.Manual of Petroleum Measurement Standards Chapter 7-Temperature Determination
7.2.3 The following terms are defined in 7.2.3.1through7.2.3.9 as they apply to this standard. 7 .2.3.1 Discrimination is the ability to sense and record the actual temperature of a liquid to the specified tempera- ture increments. 7 .2.3.2 A temperature measurement device consists of a sensor, transmission medium, and readout equipment in an configuration to determine the temperature of a liquid for measurement purposes. 7.2.3.3 A temperature sensor consists of a sensing clement and its housing, if any, and is defined as the part of a temperature device that is positioned in a liquid the temper- ature of which is being measured. 7 .2.3.4 A field standard test measure is a portable certi- fied vessel which is primarily used for the of prover water draw calibrations (see Chapter 1, Test Measures.fi.eld 7.2.3.5 scale (°C) is a temperature scale with the ice point at zero degrees and the boiling point of water at The Celsius scale (°C) is the international name for the Centigrade scale. [°C = 519 (°F – 32)]. 7.2.3.6 The Fahrenheit scale is a temperature scale on which the freezing point of water is 32 degrees and the boiling point 212 degrees. both at standard pressure. [°F = 9/5°C + 32]. 7 .2.3.7 A complete ” immersion thermometer is a mometer designed to indicate temperatures correctly when the entire thennometer is exposed to the temperature being measured. No ASTM thermometer is designed to be used at complete immersion. 7 .2.3.8 A partial-immersion thermometer is a ther- morn designed to indicate temperatures correctly when the bulb and a specified part of are exposed to the temperature being measure.
7.2.4 Selecting a Temperature Device Accuracy requirements, mechanical limits, operating limits, ambient conditions, and individual preferences must be considered when a temperature device to used for temperature determination on a metered stream or meter addition, the ability of the temperature device to make a discrimination (see 7.2.3 for definition) must Table 1 provides a guide to the minimum acceptable discrimination for dynamic determination in custody transfer measurement of petroleum and petroleum products. The use of a temperature device that can perform to a more stringent discrimination than that outlined in ’ Table 1 is acceptable provided that the selection, installation, mainte- nance, and calibration practices are adequate to ensure temperature-device performance to chosen and agreed to by all parties involved.