Factors that affect accuracy of thermocouple
The error in measring temperature with thermocouples with any instruments is related sveral fators that combine together to affect the overall accuracy of the measurment:
1.Thermocople wire error:this is the error resulting from the fact that a given sample of thermocouple wire will not exactly meet the temperature versus millivolt realtionship given the standard tables.The most accurate designation is for Type T thermocouple.The errors allowed for T type over the range -40 to 130℃ are 1.0 for standard wire and 0.5℃ for speical limits of error wire.
2.Reference junction error:this is the error in determing the temperature of the reference junction. Sometimes called “cold junction”.
3.Voltage measurment error: this is error in the measurement of the small voltage produced by the temperature difference between the measuing junction and the reference junction.
4.Linearization error: the temperature vs.millivolt realtionship for thermocouples is inherently non-linerar.The accuracy of the conversion from voltage to temperature depends on the methord that is used to make this conversion.Most commonly there is a fit to standard polynomials or interpolation within the table values.Both of these methords are subjection to some degree of error.
Contact:thermocouplesupplier@gmail.com
1.Thermocople wire error:this is the error resulting from the fact that a given sample of thermocouple wire will not exactly meet the temperature versus millivolt realtionship given the standard tables.The most accurate designation is for Type T thermocouple.The errors allowed for T type over the range -40 to 130℃ are 1.0 for standard wire and 0.5℃ for speical limits of error wire.
2.Reference junction error:this is the error in determing the temperature of the reference junction. Sometimes called “cold junction”.
3.Voltage measurment error: this is error in the measurement of the small voltage produced by the temperature difference between the measuing junction and the reference junction.
4.Linearization error: the temperature vs.millivolt realtionship for thermocouples is inherently non-linerar.The accuracy of the conversion from voltage to temperature depends on the methord that is used to make this conversion.Most commonly there is a fit to standard polynomials or interpolation within the table values.Both of these methords are subjection to some degree of error.
Contact:thermocouplesupplier@gmail.com
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