Process Engineering Division – Instrumentation and Automation Section – Daily Topics – Topic No. 2020-12-05
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Process Engineering Division – Instrumentation and Automation Section – Daily Topics – Topic No. 2020-12-05: Discussion question: 317. There are two temperature measuring instruments, with measurement ranges of 0–800°C and 600–1100°C respectively. It is known that their maximum absolute error is ±6°C each. Determine their accuracy grades respectively. (5 points for only giving the result; additional points for a correct calculation process or detailed explanation)
Based on the basic error formula δm = ×100%, we obtain δm = ×100% = 0.75%; δml = ×100% = 1.2%. Therefore, according to the accuracy class scale for common industrial instruments, temperature measuring devices with a measurement range of 0–800°C should be rated at class 1 accuracy； Thermometers with a measurement range of 600–1100°C should be classified as grade 1.5.
There are two temperature measuring instruments, with measurement ranges of 0–800°C and 600–1100°C respectively. It is known that their maximum absolute error is ±6°C each. According to the formula: Maximum relative percentage error = Maximum absolute error (in absolute value) divided by (Upper limit of the scale – Lower limit of the scale), multiplied by 100%. The accuracy class (precision) is the value of the maximum relative error without the percent sign. Maximum relative error of temperature measuring instruments at 0–800°C = 6/(800–0)*100% = 0.75% ； According to the accuracy class series of common industrial instruments, the accuracy class of this instrument should be Class 1. The maximum relative error of temperature measuring instruments in the range of 600–11800℃ is = 6/(1100–600)*100% = 1.2%. According to the accuracy class scale for common industrial instruments, the accuracy class of this instrument should be 1.5.
It is 0.75% at 0–800°C, and can be classified as grade 1.0; it is 1.2% at 600–1100°C, and can be classified as grade 1.5
Based on the basic error formula δm = ×100%, we obtain δm = ×100% = 0.75%; δml = ×100% = 1.2%. Therefore, according to the accuracy class scale for common industrial instruments, temperature measuring devices with a measurement range of 0–800°C should be rated at class 1 accuracy； Thermometers with a measurement range of 600–1100°C should be classified as grade 1.5.
It is 0.75% at 0–800°C, and can be classified as grade 1.0; it is 1.2% at 600–1100°C, and can be classified as grade 1.5
There are two temperature measuring instruments, with measurement ranges of 0–800°C and 600–1100°C respectively. It is known that their maximum absolute error is ±6°C each. According to the formula: Maximum relative percentage error = Maximum absolute error (in absolute value) divided by (Upper limit of the scale – Lower limit of the scale), multiplied by 100%. The accuracy class (precision) is the value of the maximum relative error without the percent sign. Maximum relative error of temperature measuring instruments at 0–800°C = 6/(800–0)*100% = 0.75% ； According to the accuracy class series of common industrial instruments, the accuracy class of this instrument should be Class 1. The maximum relative error of temperature measuring instruments in the range of 600–11800℃ is = 6/(1100–600)*100% = 1.2%. According to the accuracy class scale for common industrial instruments, the accuracy class of this instrument should be 1.5.
The ranges are 800, 500, 6/800, 6/500 respectively, with accuracies of 0.75% and 1.2%
Based on the basic error formula δm = ×100%, we obtain δm = ×100% = 0.75%; δml = ×100% = 1.2%. Therefore, according to the accuracy class scale for common industrial instruments, temperature measuring devices with a measurement range of 0–800°C should be rated at class 1 accuracy； Thermometers with a measurement range of 600–1100°C should be classified as grade 1.5.
It is 0.75% at 0–800°C, and can be classified as grade 1.0; it is 1.2% at 600–1100°C, and can be classified as grade 1.5
Based on the basic error formula δm = ×100%, we obtain δm = ×100% = 0.75%; δml = ×100% = 1.2%. Therefore, according to the accuracy class scale for common industrial instruments, temperature measuring devices with a measurement range of 0–800°C should be rated at class 1 accuracy； Thermometers with a measurement range of 600–1100°C should be classified as grade 1.5.