SR300-D1 ClassA デジタル日射計

Industrial Class A pyranometer with heating and tilt sensor

Hukseflux is proud to introduce SR300-D1. Succeeding our market-leading SR30 model, SR300-D1 is further optimised for use on PV power plants. The sensor complies with the industrial-grade requirements for sensor surge immunity and installation safety. SR300-D1 is intended for deployment where the highest measurement reliability and accuracy are required.

  • designed for IEC 61724-1 Class A compliant PV system performance monitoring
  • internal heating for dew and frost mitigation in all climates
  • integrated surge protection, designed to withstand the extreme conditions encountered on PV power plants, upgradable to 4 kV with optional SPD01 Surge Protection Device
  • compliant with IEC 61326-1 “Industrial equipment” – rated for Industrial Electromagnetic Environments
  • enables system designers to comply with local safety regulations
  • supported by a worldwide calibration organisation for the lowest total cost of ownership
  • hemispherical solar radiationsensor tilt angle (3 components x, y and z)
ISO 9060:2018 classification
  • spectrally flat Class A pyranometer
IEC 61724-1:2021 compliance
  • meets Class A PV monitoring system requirements


  • hemispherical solar radiationsensor tilt angle (3 components x, y and z)
ISO 9060:2018 classification
  • spectrally flat Class A pyranometer
IEC 61724-1:2021 compliance
  • meets Class A PV monitoring system requirements
IEC 61724-1:2021 compliance
  • - for solar irradiance for all locations and climatic conditions - for single axis tracker and pyranometer tilt angle measurement
Dome protector
  • included (model DP01)
Status LED
  • power & communication
Instrument diagnostics
  • leakage, tilt, rotation, heating, internal humidity
  • included
Calibration certificate
  • included (content limited according to ISO/IEC 17025, section
Temperature response test of individual instrument
  • report included
Temperature response
  • < ± 0.4 % (-30 to +50 °C)
Directional response test of individual instrument
  • report included to 95 °
Accelerometer test of individual instrument
  • report included
Tilt measurement uncertainty
  • ± 1 ° (0 to 180 °) (-30 to +50 °C)
Standard cable length (not included)
  • 3 m
EMC and Surge immunity *
  • :
Equipment classification
  • Industrial Equipment
Surge Immunity
  • Level 2, test level 1 kV
with optional SPD01
  • Level 4, test level 4 kV
Electrical Safety in the workplace
  • :
Safety compliance
  • EU Low Voltage Directive (2014/35/EU) / USA National Electric Code (NFPA70)
Earthing terminal
  • included on instrument
Operation in 3 power modes **
  • :
Norma -heated, ventilated
  • < 3 W
Medium -unheated, ventilated
  • < 1 W
Low -unheated, unventilated
  • < 0.5 W
Digital communication
  • :
Communication protocol
  • Modbus RTU
RS-485 isolation voltage
  • 1.5 kV
Hardware interface
  • 2-wire RS-485
  • at standard cable length of 3 m
  • @ 24 VDC

We offer accessories for use with the SR300-D1, including electrical and mounting hardware options.

•    SPD01 Surge Protection Device (for 1 to 3 instruments) for cables longer than 3 meters and to upgrade Surge Protection to level 4
•    PID01 Pyranometer Isolation Disc, electrically insulating the instrument from the mounting platform, spring-loaded for easy levelling
•    LM01 spring-loaded levelling mount; a practical mount for easy mounting, levelling, and instrument exchange on flat surfaces 
•    TLM01 tube levelling mount with a set of bolts 
•    calibration certificate including customer name and contact information 
•    DP01 dome protector, set of 5 pieces
•    AMF03 albedometer fixture
•    PMF01 and PFM02 mounting fixtures


SR300-D1: "industrial-grade" solar radiation monitoring

Hukseflux introduces “industrial-grade” solar radiation monitoring! The all-digital heated SR300-D1 pyranometer is engineered to measure solar radiation with the utmost reliability and measurement accuracy. SR300-D1 is the successor to our SR30-M2-D1 pyranometer, renowned worldwide as the ideal instrument for use in PV system performance monitoring.

SR300-D1 continues to provide the measurement accuracy of the SR30. It may look like it as well, but in many ways the SR300-D1 is a completely new instrument, tailored for use in PV monitoring systems.

SR300-D1 complies with – Industrial-grade – Immunity, Emission, Electrical, Environmental and Safety requirements for use in outdoor industrial environments, greatly improving measurement reliability.

Ease of operation is further enhanced through extended functionality and diagnostics.

PV system performance monitoring: IEC 61724-1 Class A compliant

SR300-D1 complies with IEC requirements for “Class A” PV system performance monitoring, without the need for additional accessories. It includes: 

  • onboard heating for dew and frost mitigation
  • accredited pyranometer calibration within the required uncertainty limit
  • calibrated tilt sensor accurate within ± 1 ° as required for single axis tracker fault detection and pyranometer tilt measurement

Immunity to high voltages and currents - surges

SR300-D1 is tested and classified for Industrial Environments according to IEC 61326-1 and IEC 61000-6-2. When designing a measuring system, SR300-D1 users may reach several levels of immunity.

With the optional Surge Protection Device SPD01 this immunity can be increased to 4 kV. Up to 3 pyranometers can be protected with a single SPD01. A third-party SPD with similar specifications may be used instead.

To attain the required level of immunity for a given installation, some general system components should be included, such as:

•    lightning protection system
•    earthing and grounding network
•    external surge protection in addition to the native on-board sensor protection

Electrical safety in the workplace

A PV power plant is a potentially hazardous workplace environment. To comply with safety regulations, SR300-D1 features a dedicated earthing terminal for connection to protective earth. When the pyranometer is isolated from the mounting platform, it should still be properly earthed via this terminal. SR300-D1 allows system designers to comply with safety regulations. These are often based on EU and US electrical safety standards such as:

•    EN-50110 Operation of Electrical Installations
•    NFPA 70 National Electrical Code (NEC)

Tilt angle measurement

For PV systems with single-axis trackers, IEC 61724-1:2021 Class A systems also require a tilt angle measurement. The sensor used for this is an accelerometer. Every SR300-D1 accelerometer is individually calibrated, and temperature compensated from -30 to +50 °C, resulting in a high accuracy measurement in compliance with the required accuracy of ± 1 °. The acceleration components x, y and z can separately be read out to provide additional information about the instrument orientation.

Heated for high data availability, operation in 3 power modes

SR300-D1 includes a heater. Heating mitigates dew and frost, leading to high data availability.

SR300-D1 can be operated in 3 power modes. Overall performance in all 3 modes complies with ISO 9060 Class A classification criteria. This allows users to conserve power and continue the measurement, also when the system operating power is limited.

•    normal, < 3 W heated / ventilated for optimal dew and frost mitigation
•    medium, < 1 W unheated / ventilated for high accuracy measurement, when dew and frost are not an issue 
•    low, < 0.5 W unheated / unventilated to save power

Heating counters frost and dew deposition. In the picture on the right you see a clear difference between a heated and non-heated pyranometer.

Remote diagnostics

In addition to solar irradiance, SR300-D1 outputs several alerts and measurements for remote use, most importantly:

•    alert: instrument leakage 
•    alert: change of tilt and rotation
•    alert: heating malfunction
•    internal humidity
•    internal pressure
•    instrument tilt and rotation

Remote diagnostics reduces the need for (un)scheduled field inspection.

On-site diagnostics: status LED

The status LED provides visual feedback to a local operator. On-site, users have immediate information on instrument power and data traffic. This is especially useful during installation and field inspections.


  • PV system performance monitoring
  • scientific meteorological observations
SR300-D1 ClassA デジタル日射計
SR300-D1 ClassA デジタル日射計
  • Compliant with IEC 61724-1 Class A
  • Heated for high data availability
  • Integrated surge protection
  • Compliant with IEC 61326-1 “Industrial equipment”
  • Remote diagnostics
  • Liabilities covered: test certificates