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Temperature Bath Calibration Simulator – RTD & Thermocouple

Temperature Bath Calibration: RTD, Thermocouple and More

A temperature sensor is calibrated by comparing it with a better reference standard in the same constant-temperature bath. Follow the job like a technician: 1 Safety, 2 Choose equipment, 3 Set up (immersion, stirring, wiring), 4 Calibrate (5 points, wait for stability, record, adjust), 5 Finish safely. Mistakes show up as real errors. Use Next step to move on, Skip this step if you want to jump ahead, or Go to start.

Procedure map (click a step)

Hint

1 Safety and planning

Hot baths cause burns and fires. Never put a wet probe into hot oil (it spatters), never use water above about 95 C, and never touch a hot probe or bath.

Live bench readings

Bath set / actual
Reference standard
Sensor under test
Difference (UUT – standard)
Stability (60 s spread)
Simulated time

Results table

PointStandardUUTErrorTol +/-Result
Error (UUT minus standard) at each temperature. Blue = this run, green band = tolerance. A flat line near zero means a good sensor.

Calibration certificate and uncertainty budget

As-found worst error
As-left worst error
Reference standard (k=2)
Bath stability + uniformity
Immersion + resolution + junction
Expanded uncertainty U (k=2)
Test uncertainty ratio (smallest tolerance / U)
Result
Typical practice (follow your site procedure): traceable reference, TUR 4:1 or better, probes at the same depth in the uniform zone, wait for stability, record as-found before any adjustment, then as-left.

Which bath for which job

BathRangeStability / uniformityRemember
Ice point0 C onlyExcellentCrushed ice, only just covered with water, stirred; a primary fixed point
Stirred liquid bath5 to 150 CVery goodWater or oil; stirring is essential; do not use water near its boiling point
Hot oil bath50 to 250 CGoodFumes, flash point, never insert wet probes
Dry-block-25 to 650 CFair (longer axial gradient)Fast and portable, needs well-fitting insert sleeves, probes need long immersion
Fluidised bath100 to 700 CGoodFor high temperatures; sensors must tolerate heat and thermal shock