Is the SolarSIM-GPV an ISO9060:2018 Class A pyranometer?
Yes, the SolarSIM-GPV is fully compliant with ISO9060:2018 Class A instrument performance criteria. In addition, ISO9060:2018 specifies sub-classifications of 'spectrally flat' and 'fast response'. The SolarSIM-GPV is spectrally flat for sunlight and a 'fast response' version of the SolarSIM-GPV is available as an option. The SolarSIM-GPV is the only Class A pyranometer that is able to accurately resolve both broadband irradiance and PV spectral correction factors.

Why would I choose a SolarSIM-GPV over a traditional pyranometer or reference cell?
Thermopile pyranometers do a good job of measuring broadband irradiance, but are spectrally blind and are unable to quantify spectral effects. Failing to account for spectral effects introduces spectral uncertainty into PV performance models and operating metrics. Spectral uncertainty can be as high as 5% on an annual basis, or up to 40% on an instantaneous basis. The SolarSIM-GPV allows users to accurately quantify and eliminate spectral uncertainty leading to improved performance prediction and analysis. The SolarSIM-GPV is the only Class A pyranometer that provides the capability to accurately quantify broadband irradiance and spectral effects within a single sensor.

What is the cosine response and why does it matter?
The cosine response relates to how accurately a global irradiance sensor measures sunlight an angles away from the normal. The SolarSIM-G, SolarSIM-GPV, SolarSIM-3C and SolarSIM-UV are specifically designed to achieve best-in-class cosine response.

How do the SolarSIMs work?
The SolarSIMs are software augmented multi-filter radiometers. They use filtered photodiodes to make precise, multi-spectral measurements of the solar spectrum in several narrow wavelength bands. These measurements then inform the SolarSIMs' software to accurately resolve the complete solar spectrum, total global irradiance and other data streams under all sky conditions.

How often should I calibrate my SolarSIM?
We recommend recalibration every two years in order to ensure the highest measurement accuracy. Recalibration is performed on-sun, at Spectrafy HQ in Ottawa, Canada. Please contact us prior to shipping your unit in order to ensure the swiftest calibration process possible.

Does Spectrafy sell complete measurement systems?
Yes, we can provide you with a complete turn-key system so you can hit the ground running with your SolarSIM measurements.

How do I connect a SolarSIM to my datalogger?
The SolarSIMs communicate via RS-485 ASCII. As such they can connect to any datalogger that accepts RS-485 or RS-232 inputs. Sections 4 and 6 of the SolarSIM-G User Manual provides details regarding data logger integration, as do our data logger app notes found in the 'Software and Datalogger Support' section of the website.

Why would I use a SolarSIM over a spectroradiometer?
The SolarSIMs offer a number of benefits over traditional field spectroradiometers for the measurement of solar spectral irradiance. These include greater accuracy, higher spectral resolution, broader wavelength range, greater thermal stability, smaller size and weight, better reliability, better cosine response, lower power consumption as well as lower capital and maintenance costs.

What is the difference between the SolarSIM-D2 and the SolarSIM-G?
The SolarSIM-D2 is designed to measure direct solar irradiance, whereas the SolarSIM-G measures global irradiance.

How does the process of upgrading my SolarSIM to add additional measurement functions work?
The SolarSIM-G can be purchased with any or all of its measurement capabilities activated. Additional measurement options can be added at any point in the future via a simple software upgrade. At the same time, users can also choose to have their historical data reprocessed, to include the new measurand(s) from inception.

How are the SolarSIMs calibrated?
All SolarSIM-G production units undergo electrical, thermal and optical calibration. The optical calibration is performed on-sun against our reference SolarSIM-G sensors. The reference sensors are calibrated for absolute irradiance at NREL in Golden Colorado and are traceable to NIST Spectral Irradiance Standard Model FEL lamps.

What OS is the SolarSIM software compatible with?
The SolarSIM software is compatible with Windows and Linux.

What does the SolarSIM software do?
The core of the SolarSIM software is a proprietary radiative transfer model that uses the SolarSIM's multi-spectral measurements of sunlight, along with its measurements of ambient temperature, pressure and humidity to reconstruct the solar spectral irradiance over the 280-4000nm range. It is available as a GUI and as a command-line executable.

Does the SolarSIM-D2 require a solar tracker?
Yes, the SolarSIM-D2 needs to be pointing at the sun in order to function. This is typically achieved using an automated, dual-axis sun tracker and we sell the ST-5 sun tracker for this purpose.