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Enabling better global research outcomes in soil, plant & environmental monitoring.

SNiP-HFP for Heat Flux

The SNiP-HFP is a 'Sensor Node Integrated Package' for LoRaWAN or CAT-M1 communication of real-time heat flux measurement for continuous environmental monitoring.


The SNiP-HFP intergrates 1x MFR-NODE with 1x HFP01 Heat Flux Sensor and 2x THERM-SS Temperature Sensors to a site’s unique network, communication and power requirements.

The HFP01 Heat Flux Sensor is the world’s most popular heat flux sensor for heat flux measurement in soil as well as through walls and building envelopes. By using a ceramic-plastic composite body the total thermal resistance is kept small.

The THERM-SS is a high quality, low cost sensor for measurement of soil, air or liquid temperature. The sensor consists of a thermistor embedded in a protective stainless steel body. THERM-SS sensors can be used in a wide range of applications from soil monitoring and climate control to concrete monitoring and explosive testing.


See Further Specifications on the MFR-NODE
See Further Specifications on the HFP01 Heat Flux Sensor
See Further Specifications on the THERM-SS Temperature Sensor

Further parameters can be added to SNiP-HFP, without requiring loggers to match each distinct sensor, substantially reducing the cost of getting a fuller picture on the application.

HFP01 serves to measure the heat that flows through the object in which it is incorporated or on which it is mounted. The actual sensor in HFP01 is a thermopile. This thermopile measures the differential temperature across the ceramic-plastic composite body of HFP01. The HFP01 is completely passive, generating a small output voltage proportional to the local heat flux.

Using HFP01 is easy. For readout one only needs an accurate voltmeter that works in the millivolt range. To calculate the heat flux, the voltage must be divided by the sensitivity; a constant that is supplied with each individual instrument.

HFP01 can be used for in-situ measurement of building envelope thermal resistance (R-value) and thermal transmittance (H-value) according to ISO 9869, ASTM C1046 and ASTM 1155 standards.

Traceability of calibration is to the “guarded hot plate” of National Physical Laboratory (NPL) of the UK, according to ISO 8302 and ASTM C177.

A typical measurement location is equipped with 2 sensors for good spatial averaging. If necessary two sensors can be put in series, creating a single output signal.


The Multifunction Research Node has been designed to provide flexible communication, sensor and power options.

The MFR-NODE supports SDI-12 and 4 x dry contact digital inputs as well as optionally 2x differential / 4x single ended analogue inputs. The MFR-NODE supports sensors with higher power requirements; a solar panel can charge either the internal lithium-ion battery or both the node and sensor can be powered by an external 12V system (e.g. battery or mains source). Optional CAT-M1 provide an option for remote installation and in areas outside the range existing LoRaWAN networks. The optional multiconstellation GNSS ensures you won’t lose track of your device. The MFR-NODE has an onboard 8GB SD Card to provide data logging capabilities and full data redundancy in the event of temporary loss of communications or dropped packets – ideal for research applications.

  • LoRaWAN™ low-power long-range connectivity
  • 8GB SD Card for data storage
  • Supporting SDI-12, 2 x 32-bit dry-contact counting digital inputs.
  • Optional 24-bit ADC for 2x differential / 4x single ended sensor.
  • Optional CAT-M1
  • Solar rechargeable Lithium-ion or external 12V power options
  • Optional Multi-constellation GNSS
  • External solar/battery input: 12-32V DC.


HFP01 Heat Flux Sensor

The HFP01 heat flux plate offers a solution for measuring heat fluxes.

Suggested use

  • meteorology
  • building physics
  • H-value and R-value determination
  • building climate control

 HFP01 Specifications

Nominal sensitivity 50 µV/Wm²
Temperature range -30 to +70°C
Range -2000 to +2000 W/m²
Sensor thermal resistance < 6.25 10-3 Km²/W
Calibration traceability NPL, ISO 8302 / ASTM C177
Expected typical accuracy (12 hr totals) within +5%/-15% in most common soil, within +5%/-5% on walls