Thermocouples are workhorses for temperature measurement, but their data loggers can turn good readings bad if not controlled properly. From electromagnetic interference to wrong wire types, small issues add up—here’s how to keep accuracy tight, no matter the scenario.

Fight interference:

· EMI/RFI: Power tools, motors, or radio towers can corrupt signals. Use shielded thermocouple wire (e.g., Teflon-insulated with a braided shield) and ground the shield at one end (not both—avoids ground loops).

· Thermal EMF: When different metals touch (e.g., a copper connector on a K-type thermocouple), tiny voltages form. Use isothermal blocks to keep connections at the same temperature.

Match logger to thermocouple type:

· K-type (most common): Loggers with cold-junction compensation (CJC) work best—they adjust for room temperature changes.

· J-type (for low temps): Ensure the logger’s input range goes down to -210°C (some cheap ones stop at -50°C).

· T-type (precision): Use loggers with 24-bit ADCs to capture their ±0.5°C accuracy.

Scenario hacks:

· High-vibration areas (e.g., engine tests): Use strain-relief cable clamps to stop wires from breaking at the logger input.

· Wet environments (e.g., humidity chambers): Choose loggers with IP65 ratings—sealed against dust and water jets.

· Remote locations: Battery-powered loggers with 100+ hour life (look for “low-power mode”) beat plug-in models.

Check accuracy monthly:
Use a calibration bath (e.g., 0°C ice water, 100°C boiling water) to verify the logger. A drift of >1°C means it’s time to recalibrate.

Having trouble with jumpy readings? Share your setup (thermocouple type, environment), and we’ll diagnose the issue.