The SNiP-SR1 is a preconfigured 'Sensor Node Integrated Package' for LoRaWAN communication of real-time measurements of solar radiation, for continuous environmental monitoring.
The SP-110 Milivolt Pyranometer is an amplified sensor with a milivolt output and exhibits excellent cosine response to measure solar radiation. Total shortwave radiation is an important component in determining evapo-transpiration rates, energy balance, net radiation as well as monitoring solar power panels.
Further parameters can be added to the SNiP without requiring loggers to match each distinct sensor, substantially reducing the cost of getting a fuller picture on the application.
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 (Wm-2, equal to Joules per second per square meter). Pyranometers are sensors that measure global shortwave radiation.
Apogee SP series pyranometers are silicon-cell pyranometers, and are only sensitive to a portion of the solar spectrum, approximately 350 – 1100 nm (approximately 80 % of total shortwave radiation is within this range). However, silicon-cell pyranometers are calibrated to estimate total shortwave radiation across the entire solar spectrum. Silicon-cell pyranometer specifications compare favourably to specifications for World Meteorological Organization (WMO) moderate and good quality classifications and specifications for International Organisation of Standardisation (ISO) second class and first class classifications, but because of limited spectral sensitivity, they do not meet the spectral specification necessary for WMO or ISO certification.
Typical applications of silicon-cell pyranometers include incoming shortwave radiation measurement in agricultural, ecological, and hydrological weather networks, and solar panel arrays.
Apogee Instruments SP series pyranometers consist of a cast acrylic diffuser (filter), photodiode, and signal processing circuitry mounted in an anodised aluminium housing, and a cable to connect the sensor to a measurement device. Sensors are potted solid with no internal air space and are designed for continuous total shortwave radiation measurement on a planar surface in outdoor environments. SP series sensors output an analogue voltage that is directly proportional to total shortwave radiation from the sun. The voltage signal from the sensor is directly proportional to radiation incident on a planar surface (does not have to be horizontal), where the radiation emanates from all angles of a hemisphere.
The AD-NODE is designed for those requiring precision in their analogue and digital measurements. With a 24-bit ADC, the AD-NODE supports two RTDs, a 0–10V with compressing range and a 4–20mA input. Each of the four dry-contact digital inputs is capable of simultaneously sampling at 1 kHz, with periodic reporting. Settings on the device can be altered remotely via LoRaWAN™ or locally via USB.
All Apogee pyranometers incorporate a silicon-cell photodiode that measures total shortwave radiation with a sensor housing design that features a fully potted, domed-shaped head making the sensor fully weatherproof and self-cleaning.
|ISO 9060:2018||Class C (previously known as second class)|
|Output (Sensitivity)||0.2 mV per W m-2|
|Output Type||0 to 400 mV|
|Digital Input Voltage||–|
|Calibration Factor (reciprocal of output)||5 W m-2 per mV|
|Calibration Uncertainty||± 5 %|
|Measurement Repeatability||Less than 1 %|
|Long-term Drift||Less than 2 % per year|
|Non-linearity||Less than 1 % up to 2000 W m-2|
|Response Time||Less than 1 ms|
|Field of View||180°|
|Spectral Range||360 to 1120 nm|
|Directional (Cosine) Response||± 5 % at 75° zenith angle|
|Temperature Response||0.04 ± 0.04 % per C|
|Operating Environment||-40 to 70 C; 0 to 100 % relative humidity;
can be submerged in water up to depths of 30 m
|Dimensions||24 mm diameter, 33 mm height|
|Mass (with 5 m of cable)||90 g|