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Delta-T SPN1 Sunshine Pyranometer

Collect high-quality global and diffuse radiation as well as sunshine duration using the Delta-T SPN1 Sunshine Pyranometer.

  • Delta-T SPN1 Sunshine Pyranometer
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Configuration Options

The Delta-T SPN1 Sunshine Pyranometer measures global (total) and diffuse horizontal irradiance as well as sunshine duration. It is an affordable alternative to shade-ring pyranometers, pyrheliometers, and traditional sunshine recorders. The SPN1 Sunshine Pyranometer is exceptionally easy to use, works at any latitude, and does not require routine adjustment or polar alignment. 

Direct and Diffuse Radiation

The SPN1 Sunshine Pyranometer uses an array of seven miniature thermopile sensors and a computer-generated shading pattern to measure the direct and diffuse components of incident solar radiation. The SPN1 Sunshine Pyranometer computes direct radiation by subtracting the diffuse from the global (total) radiation.

Sunshine Duration

The WMO threshold for bright sunshine is 120 W.m-2 in a plane perpendicular to the direct solar beam. The SPN1 Sunshine Pyranometer uses an algorithm based on the ratio of direct to diffuse radiation, combined with their absolute values, to estimate sunshine duration to within a few percent of the WMO standard.

The SPN1 Sunshine Pyranometer does not need to be adjusted or re-positioned to track the sun  a distinct advantage over devices with shadow rings. There are no complex electro-mechanical assemblies and no burnt paper tracks to interpret.

Outputs and Logging

The SPN1 Sunshine Pyranometer provides two analog voltage outputs for global and diffuse radiation, and a digital output for sunshine duration. The sensor is compatible with the SymphoniePRO Data Logger. The SPN1's signal output is compatible with SymphoniePRO's channels 16-19  but depending on your configuration, you may also need a P-SCM card (P-SCM #9132).

This sensor comes with a certificate of calibration and 5m cable. Note that as with all thermopile pyranometers, regularly scheduled maintenance is imperative to achieve the sensor’s specified performance.


  Delta-T SPN1 Sunshine Pyranometer (#10535)
Sensor type Thermopile solar radiation sensor
  • Solar resource assessment and monitoring
  • Meteorological studies
  • Argonomy & plant science
Sensor range 0W/m2 to 2000W/m2
Spectral range 400nm to 2700nm
Instrument compatibility
  • NRG SymphoniePRO logger with P-SCM#9132
  • Logger measurement range 0 W/m2 to 1500W/m2
Measurement range Sunshine status threshold:
120W/m2 in the direct beam
Output signal  
Sensitivity Analogue output sensitivity:
  • 1mV = 1W/m2

    Spectral sensitivity variation:
  • 10% (typical)
Linearity > 99%
Stability Recalibration recommended every 2 years
Response time 100ms (typical)
Accuracy Total (Global) and Diffuse radiation:
  • ±5% Daily integrals
  • ±5% ±10W/m2 Hourly averages
  • ±8% ±10W/m2 Individual readings

    Sunshine status:
  • ±10% sun hours with respect to the threshold

    Cosine correction:
  • ±2% of incoming radiation over 0-90° Zenith angle

    Azimuth angle
  • ±5% over 360° rotation
Output signal range 0 - 2500mV

Sunshine status output:
  • No sun = open circuit
  • Sun= short circuit t ground
Resolution 0.6W/m2 = 0.6mV
Performance characteristics  
Tilt Tilt response:
Power requirements  
Supply voltage 5V - 15V DC
Heater supply voltage 12V - 15V DC
Heater supply current Up to 1.5A
Power Required <30μA (asleep) to 2mA (awake)
Mounting 3 x M5 tapped holes in base at 108mm dia., 120° spacing
Operating temperature range -40 to +70°C (-40 to +158°F)
Temperature dependence Temperature coefficient:
0.02% per °C (typical)
Other Zero offsets:
  • < 3W/m2 for a change of 5°C/hr in ambient temperature
  • < 3W/m2 dark reading

    Latitude capability:
  • -90° to +90°
Connections RS232 Connector:
  • 5-pin M12
    Signal output & power-in connector:
  • 8-pin M12
Weight 786g (1.73 lb)
Dimensions 126mm dia. x 94mm high (5" dia. x 3.7" high)
Enclosure Environmental sealing: IP67

Customer Service

+1 802-482-2255

Mon – Fri: 8:30am – 5:00pm Eastern Time (GMT-5)