The SK01-DP2 version incorporates a special interference reflector to limit its sensitivity to the Photosynthetically Active Radiation region of the solar spectrum (400-700nm).
The SK01-DP2 sensor is an major upgrade of our popular SK01-D sensor. The body parts have been extensively revised to raise the weatherproof rating to IP67 (immersion proof), and the aluminium components are now hard anodised for increased durability. The SK01-DP2 retains the convenient features of protective glass dome, bubble level, and in-built signal amplifier.
|Response time (to 95%):||30ms|
|Non-stability (per year):||< ± 2%|
|Non-linearity:||< 1 %|
|Directional response (30°- 80° zenith):||< 1 ms< ± 30 W.m-2 (ISO9060 2nd class)|
|Spectral response (w.r.t clear sun), SK01-D2:||-6% (heavy haze) to +4% (bright cloud)|
|Temperature response:||< ± 0.15% per °C|
|Tilt response:||no tilt error|
In-built signal amplifier to give a millivolt output for easy measurement.
Chopper stabilised (for zero amplifier drift), with overvoltage & polarity reversal protection.
SK01-D2 spectral response varies with wavelength so it is calibrated for solar spectral distribution and is not recommended for use in indirect or artificial lighting.
Sealed to IP66, with internal desiccant (non-toxic silica-gel).
User’s Instructions and Calibration Certificate included.
|Viewing Angle||2 pi steradians|
|Spectral Range (nominal)||SK01-DP2: 400-700nm|
|Irradiance||SK01-DP2: 0-3000 µ mol.s-1.m-2|
|Sensitivity||SK01-DP2: 0.5mV/µ mol.s-1.m-2|
|Calibration Accuracy||± 3%|
|Operating Temperature||-35°C to +60°C|
|Power Requirement||5.5V to 14.5VDC, 3mA|
|Sensor Type||silicon photodiode|
|Mounting||central M5 hole; adjustable feet|
|Shipping Size & Weight; Net Weight||150 x 150 x 150mm, 0.5kg, 0.3kg|
Solar radiation at Earth’s surface is typically defined as total radiation across a wavelength range of 280 to 4000 nm (shortwave radiation). Total solar radiation, direct beam and diffuse, incident on a horizontal surface is defined as global shortwave radiation, or shortwave irradiance (incident radiant flux), and is expressed in Watts per square meter.
The SK01-D2 pyranometer is for measuring solar global radiation. It uses a silicon photodiode detector shielded by a cosine corrected diffuser and has a glass dome to keep debris off the diffuser. It is sealed and fully weatherproof. The detector signal is boosted by a low noise amplifier that is drift stabilised.
Select a site that has an unobstructed view of the sun from sunrise to sunset. Place the instrument on a flat horizontal platform and adjust the feet with a 7mm A.F. spanner until the circular level is centered. Secure the instrument to the platform with a 5mm holding screw in the centre of the base; the screw should be brass or stainless steel.
Power up the instrument by connecting the lead to the terminals of a 5.5-14.5V DC supply (a fresh 9V PP3 alkaline battery will power the instrument for up to 200 hours). red to +ve blue to -ve.
Measure the output signal by connecting the lead to a voltmeter, data-logger, chart recorder, or similar instrument. yellow (or white) to +ve clear (or green) to -ve.
Note: the instrument has a low current drain and a 50ms settling time; it is suitable for unattended installation with a battery operated data logger periodically powering it up.
The SK01-D2 is calibrated for use in unobstructed daylight. The calibration is by outdoors comparison to a reference pyranometer. It is recommended that the calibration be checked annually.
The output signal is factory set to 1mV/W.m -2 (so 1000W.m -2 of sunshine = 1 volt).
Photodiode detectors do not have a flat spectral response and are therefore not recommended for use in indirect or artificial light. In daylight the spectral selectivity can cause small deviations from ideal response: global irradiance will tend to be overestimated by up to 2% in bright cloud conditions, and underestimated by up to 6% in heavy overcast conditions. The cumulative solar energy error from spectral selectivity is small.