Metrology Knowledge Hub & Precision Calculators
Authoritative engineering standards, real-time sensor solvers, Callendar-Van Dusen conversion algorithms, and EURAMET cg-13 calibration procedures provided by Dual Brothers.
RTD PT100 / PT1000 Solver
Dew Point & RH Solver
Pressure Metrology Matrix
Tachometer RPM & Frequency
📘 Standard Metrology Reference Standards (ITS-90 & IEC)
Fundamental equations and tolerance limits applied across ISO/IEC 17025 accredited calibration laboratories.
| Temperature (°C) | Class 1/10 DIN (±°C) | Class A (±°C) | Class B (±°C) | Nominal PT100 Resistance |
|---|---|---|---|---|
| -50.00 °C | ±0.035 °C | ±0.250 °C | ±0.550 °C | 80.31 Ω |
| 0.00 °C (Ice Point) | ±0.030 °C | ±0.150 °C | ±0.300 °C | 100.00 Ω |
| 50.00 °C | ±0.040 °C | ±0.250 °C | ±0.550 °C | 119.40 Ω |
| 100.00 °C (Steam Point) | ±0.050 °C | ±0.350 °C | ±0.800 °C | 138.51 Ω |
| 200.00 °C | ±0.070 °C | ±0.550 °C | ±1.300 °C | 175.86 Ω |
| 400.00 °C | ±0.110 °C | ±0.950 °C | ±2.300 °C | 247.09 Ω |
| 600.00 °C | ±0.150 °C | ±1.350 °C | ±3.300 °C | 313.71 Ω |
1. EURAMET cg-13 Dry Well Calibrator Axial & Radial Homogeneity
Dry well temperature calibrators (like our DB Therion Series) must satisfy EURAMET cg-13 metrology guidelines. The thermal block achieves radial uniformity within ±0.03°C and axial gradient less than ±0.05°C over the bottom 40mm immersion zone. Always maintain minimum insertion depth of 15× sheath diameter to eliminate ambient stem conduction loss.
2. ASTM E2847 Infrared & Blackbody Cavity Radiation Calibration
Non-contact infrared thermometers and thermal imagers require calibration against certified blackbody cavities (like our DB Pyrovia Series). The target emissivity (ε) is maintained between 0.95 and 0.995 with target uniformity exceeding ±0.1°C. Calibration is performed across multiple isothermal plate points with fixed distance-to-spot (D:S) alignment.
3. Guide to the Expression of Uncertainty in Measurement (GUM) Budget
Uncertainty evaluation is formulated via combined standard uncertainty: \( u_c(y) = \sqrt{\sum (\frac{\partial f}{\partial x_i})^2 u(x_i)^2} \). Type A evaluations quantify repeatability from n ≥ 10 repeat measurement cycles; Type B incorporates manufacturer master standard calibration drift, immersion thermal gradient, display resolution, and ambient atmospheric stability.
Need Bespoke Calibration Instruments or Technical Quotation?
Dual Brothers manufactures and exports ISO/IEC 17025 accredited dry wells, 1000-bar hydraulic test benches, humidity chambers, blackbody sources, and custom RTD sensors to 80+ countries worldwide.