Digital Class A (secondary standard) Pyranometer with Heating and Tilt Sensor

Welcome to the next level in solar radiation monitoring! The all-digital heated SR30-M2-D1 offers the highest accuracy and highest data availability: using Recirculating Ventilation and Heating (RVH™) technology, SR30 outperforms pyranometers equipped with traditional ventilation systems. SR30 is the ideal instrument for use in PV system performance monitoring and meteorological networks. It measures the solar radiation received by a plane surface, in W/m², from a 180 ° field of view angle. SR30 is an ISO 9060 spectrally flat Class A (previously “secondary standard”) pyranometer. It is employed where the highest measurement accuracy is required. SR30-M2-D1 offers several advantages over competing pyranometers:

  • Heated for high data availability, featuring new RVH™ technology
  • Compliant with IEC 61724-1:2017 Class A and B
  • Low cost of ownership
  • Remote sensor diagnostics
  • Liabilities covered: test certificates


Heated for high data availability, featuring RVH™ technology

High data availability is attained by heating of the outer dome using ventilation between the inner and outer dome. RVH™- Recirculating Ventilation and Heating – technology, developed by Hukseflux, suppresses dew and frost deposition and is as effective as traditional ventilation systems, without the maintenance hassle and large footprint.

The dome of SR30 pyranometer is heated by ventilating the area between the inner and outer dome. RVH™ is much more efficient than traditional ventilation, where most of the heat is carried away with the ventilation air. Recirculating ventilation is as effective in suppressing dew and frost deposition at less than 3 W as traditional ventilation is at 10 W. RVH™ technology also leads to a reduction of zero offsets

Compliant with IEC 61724-1:2017 Class A and B

IEC 61724-1: Photovoltaic System Performance Monitoring – Guidelines for Measurement, Data Exchange and Analysis – requires ventilation and heating for Class A monitoring. Only SR30 offers both, without the need for additional accessories. Most competing pyranometers do not even comply with Class B, which requires heating.

Remote sensor diagnostics

In addition to solar irradiance, SR30 outputs sensor diagnostics such as:

  • tilt angle
  • Internal ventilator speed (RPM)
  • Internal humidity
  • Heater current

Remote diagnostics permits real-time status monitoring, reducing the need for (un)scheduled field inspections.

Tilt angle measurement included

SR30 includes a tilt sensor. This is very practical for remote checks of instrument condition or to monitor PV systems with solar trackers. The sensor measures with high accuracy, within 1 ˚, and is tested and temperature compensated between -30 and + 50 ˚C. SR30-M2-D1 offers improved electronics over its predecessor SR30-D1


Spectrally flat as required for meteorology and PV monitoring

The new ISO 9060:2018 version defines pyranometer classes A, B and C. The standard also adds a new subclass, called “spectrally flat”. The vast majority of users needs to use instruments of the spectrally flat subclass; only spectrally flat instruments measure with high accuracy, also when a cloud obscures the sun, or when the irradiance includes reflected radiation. These situations occur for example when you measure Global Horizontal irradiance (GHI) under partly or fully cloudy skies, when you measure Plane of Array (POA), albedo or net-radiation. Normal instruments, just of class A, B or C, and not spectrally flat, only measure accurately under clear sunny skies.


New Sensor Manager software

SR30-M2-D1 is delivered with new Hukseflux Sensor Manager software, version v2021. It provides a user interface for communication between a PC and digital Hukseflux pyranometers and pyrheliometers with a Modbus interface. The software allows the user to locate, configure and test one or more sensors and to perform simple measurements using a PC. The Sensor Manager software is supplied with the SR30-M2-D1 on a USB flash drive. It can also be downloaded: The new v2021 version of the Sensor Manager replaces previous versions such as v1817 and v1920 beta. Always use the latest version of the software. Need support in using the v2021 software? Please consult the separate Sensor Manager user manual.

Suggested Use

  • PV system performance monitoring
  • Scientific meteorological observations

Areas of Application

  • Meteorology / surface energy flux measurement
  • Solar energy / PV system performance monitoring


  • AMF03
  • SHR02
  • PMF01
  • PMF02
  • Sensor Manager
  • CMF01



Hemispherical solar radiation

ISO 9060:2018 classification

spectrally flat Class A (secondary standard)

IEC 61724-1:2017 compliance

Class A


National Meteorological NetworksPV monitoring commercial and utility scale,meteorology / climatology, other


with RVH Recirculating Ventilation and Heating

WMO performance level

high quality pyranometer

Calibration uncertainty

< 1.2 % (k = 2)


Sensor tilt angle

Tilt measurement uncertainty

± 1 ° (0 to 90 °)





Technology employed

Recirculating Ventilation and Heating (RVH™)

Standard operating mode

heated and ventilated

Calibration traceability

to WRR

Calibration registers

Accessible to users

Spectral range

285 to 3000 x 10⁻⁹ m

Rated operating temperature range

-40 to +80 °C

Temperature response

< ± 0.4 % (-30 to +50 °C)

Temperature response test of individual instrument

Report included

Directional response test of individual instrument

Report included

Tilt sensor test of individual instrument

Report included

Standard cable length

5 m

Rated operating voltage

5 to 30 VDC range

Operating condition

heater and ventilator [OFF] in low power mode

Zero offset a

< 2 W/m²

Power consumption

< 0.1 W at 12 VDC in low power mode

Digital Output



irradiance in W/m², instrument body temperature in °C, tilt angle in °, internal humidity in % and ventilator speed in RPM

Communication protocol


Transmission mode


Hardware interface

2-wire (half duplex) RS-485

Version order codes

SR30-M2-D1, SR30-M2-D1-LM01, SR30-M2-D1-TLM01


• Spring-loaded levelling mount (Specify article number LM01 when ordering)
• Tube levelling mount with set of bolts (Specify article number TLM01 when ordering)
• Longer cable; 10 and 20 metres


Download Product Brochure

Download Product Manual

Important changes SR30-M2-D1 memo

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