Introduction
Calibrating thermocouples demands precision. Follow this workflow to minimize errors and maximize repeatability.

Step 1: Pre-Calibration Checks

• Furnace Warm-Up: Preheat to the target temperature (e.g., 500°C) and stabilize for 30+ minutes.

• Thermocouple Inspection: Check for oxidation, cracks, or insulation damage.

Step 2: Positioning

• Place the thermocouple junction at the furnace’s geometric center.

• Use ceramic insulators to avoid contact with furnace walls.

• For multi-sensor calibration, ensure equal spacing to prevent thermal interference.

Step 3: Reference Standards

• Insert a NIST-traceable PRT (Platinum Resistance Thermometer) or master thermocouple beside the unit under test (UUT).

• Record readings at 100°C intervals (e.g., 100°C, 200°C, up to max temperature).

Step 4: Post-Calibration

• Certify results with a calibration report (include date, technician, and environmental conditions).

• Apply corrections to the thermocouple’s output table if errors exceed acceptable limits.

Avoid These Mistakes:

• Skipping stabilization time.

• Using damaged reference probes.

• Ignoring ambient temperature effects.