Ultra-high resolution heat flux sensor HFP03

calibration

Ultra-sensitive heat flux plate HFP03 for measurement of very small heat fluxes in soil and through walls and building envelopes. The sensor is passive (thermopile) and provides a small voltage output proportional to heat flux; it is designed with a ceramics-plastic composite body to keep total thermal resistance small and enable measurement of fluxes below 1 W/m².

Key features

• Exceptionally high sensitivity suitable for fluxes below ~1 W/m²
• Ceramics-plastic composite body (low total thermal resistance)
• Thermopile sensor — passive, no power required
• Direct connection to common data logging systems; heat flux (W/m²) obtained by dividing sensor output voltage by sensitivity on the calibration certificate
• Alternative: several HFP01 sensors can be connected electrically in series as an alternative to HFP03

Suggested use / Applications

• Measurement of extremely small heat fluxes (below ~1 W/m²)
• Geothermal heat flux measurement
• Embedding in or mounting on walls, building envelopes or soil for conductive/convective flux measurement

Technical specifications

• Measurand: heat flux
• Sensing area: 64 x 10⁻⁴ m²
• Sensor thermal resistance: 71 x 10⁻⁴ K/(W/m²)
• Sensor resistance range: 10 to 32 Ω
• Sensor thickness: 5.4 x 10⁻³ m
• Uncertainty of calibration: ± 6 % (k = 2)
• Measurement range: -2000 to 2000 W/m²
• Sensitivity (nominal): 500 x 10⁻⁶ V/(W/m²)
• Rated operating temperature range: -30 to +70 °C
• Cable diameter: 4 x 10⁻³ m
• IP protection class: IP67
• Standard cable length: 5 m (options: 10, 15, 20, 30, 40 m)