Standard thermocouple classification: First class standard platinum rhodium thermocouple WRPB-1 S-type 0-1300 ℃
Second class standard platinum rhodium thermocouple WRPB-2 S-type 0-1300 ℃
Common specifications and models WRPB-1 S-type 0-1300 ℃ default 0.5 * 1000m Other lengths can be customized
WRPB-2 S-type 0-1300 ℃ default 0.5 * 1000m, other lengths can be customized
1. When the measuring end of a first-class and second-class standard thermocouple (hereinafter referred to as a standard thermocouple) is at a copper point (1084.62 ℃), an aluminum point (660.323 ℃), an antimony point (630.63 ℃), and a zinc point (419.527 ℃), and the reference end temperature is 0 ℃, its thermoelectric potential should meet the following requirements:
E(tCu)=（10.575±0.015）mv
E(tAl)=5.860+0.37[E(tCu)-10.575]±0.005mV
E(tAsb)=5.553+0.37[E(tCu)-10.575] ±0.005mV
E(tZn)=3.447+0.18[E(tCu)-10.575] ±0.005 mV
2. The stability of a standard thermocouple is determined by the change in electromotive force at its copper point (the difference between two thermoelectric potentials). Newly manufactured second-class standard thermocouples do not exceed 5uV, and the annual change in thermoelectric potential at the copper point of a second-class standard thermocouple in use does not exceed 10uV.
3. Standard thermocouples that are frequently used should undergo necessary supervisory verification based on their usage to ensure accurate and reliable measurement values.
The supervisory verification of standard thermocouples is carried out using first-class standard thermocouples or second-class standard thermocouples that are not frequently used as standards. The qualification of the thermocouples is determined by the difference between the thermoelectric potential measured on the copper point and the thermoelectric potential value given in the metrological verification certificate (the difference is not greater than 7uV).
4. According to the metrological verification, the standard thermoelectric spot check certificate in accordance with JJG75-1995 "National Metrological Verification Regulations for Standard Platinum Rhodium 10 Platinum Thermocouples" is issued as the product's factory qualification certificate. The significant digits of the standard thermocouple thermoelectric potential value given in the certificate are three decimal places (see subsequent certificate data for details).
structure
The standard platinum rhodium 10 platinum thermocouple consists of a complete product consisting of wire material, insulated ceramic tube, and outer packaging box. The standard thermocouple has a platinum rhodium 10 wire positive electrode and a platinum wire negative electrode, and is fitted with a 550mm long double hole insulated ceramic tube; Refer to the positive pole with a red or pink plastic tube, and the negative pole with a white or blue plastic tube; The entire product is stored in a glass outer sleeve.
Precautions for use
1. When using and storing, the ceramic and plastic tubes on the marked platinum rhodium 10 platinum thermocouple should not be removed arbitrarily, and efforts should be made to keep the mark straight and avoid severe bending of the thermocouple; Quartz outer protective tube should be added; During transportation and storage, standard thermocouples WRPB-1/WRPB-2 should be protected from severe mechanical vibrations.
2. Regular supervisory inspections and periodic verifications should be conducted in accordance with the National Metrological Verification Regulations for Standard Platinum Rhodium 10 Platinum Thermocouples (JJG75-95).
3. Please keep the calibration certificate attached to the standard thermocouple manufacturer when it leaves the factory properly. The original calibration certificate must be brought with you during the next calibration. Without a certificate, it will not be used as a standard platinum rhodium 10 platinum thermocouple calibration.
National product standards
Implementation of First Class and Second Class Standard Platinum Rhodium 10 Platinum Thermocouples (JJG75-1995) "National Metrological Verification Regulations for Standard Platinum Rhodium 10 Platinum Thermocouples"