three-component solar irradiance measurement
SolarBand-C3
The SolarBand-C3 is a photodiode-based pyranometer that provides highly accurate measurements of global and diffuse irradiance with no external moving parts.
The SolarBand-C3 employs three silicon photodiode detectors and an automated, internal shadowband to provide an accurate, affordable and low-maintenance solution for diffuse irradiance measurement.
| Measurands: | Global solar irradiance, diffuse solar irradiance, direct solar irradiance (calculated). |
| Technology: | Triple-photodiode pyranometer with internal automated shadowband. |
| Highlights: | Accurate diffuse irradiance measurement with no external moving parts. |
Accurate, reliable DHI measurement
The SolarBand-C3 represents an exciting step forward in the measurement of diffuse irradiance. The SolarBand-C3 combines the accuracy of an automated shadow band with the reliability of a fully enclosed system to provide accurate, affordable measurements of diffuse, global and direct irradiance, from a single, digital sensor with no external moving parts.
The SolarBand-C3 employs three photodiodes (two global, one diffuse) and an automated, internal shadow band to measure global and diffuse irradiances simultaneously. The shadow band is mounted to an internal motor that slowly rotates over the course of each day, ensuring that the diffuse sensor remains continuously shaded.
The SolarBand-C3 is built for ease-of-use and is equipped with industry-standard features such as RS-485 Modbus communication, internal diagnostics, built-in heating and third-party calibration support, while also introducing on-board GPS and automated alignment verification.
Applications for the SolarBand-C3 include solar resource assessment, PV plant operation aswell as meteorological research and monitoring networks.
All three irradiance components
| Global horizontal solar irradiance | Broadband GHI, measured via silicon photodiode |
| Diffuse horizontal solar irradiance | Broadband DHI, measured via shaded silicon photodiode |
| Direct normal solar irradiance | Broadband DNI, calculated from the global and diffuse measurements |
| Sunshine duration | Calculated from the DNI data |
The SolarBand-C3 comes with powerful software to process and visualize your data.
The SolarBand-C3's embedded software completes all data processing onboard, thereby enabling easy integrating with SCADA systems via the Modbus RTU communication protocol. In addition, for applications where it is desirable, the SolarBand-C3 ships with a Windows-based GUI to provide the user with clear visualization of its data streams.
Easily integrates with modern MET stations.
Datalogger
With RS-485 Modbus RTU digital output, the SolarBand-C3 can connect to any RS-485 capable datalogger. Sample datalogger code and Modbus register maps are available upon request.
Combox
Get your SolarBand-C3 working straight out of the box with our custom power/comms converter. The Combox allows you to connect to and power a SolarBand-C3 directly through a laptop or PC.
Serial over ethernet
The SolarBand-C3 can be connected to a networked PC/server via a suitable SoE device. Hardware recommendations are available upon request.
Diffuse Horizontal Irradiance
| Accuracy (k=2) | ± 4% Daily integral |
| ± 4% ± 5 W/m2 hourly average | |
| ± 5% ± 5 W/m2 individual readings | |
| Measurement range | 0 - 2000 W/m2 |
| Response time (95%) | < 0.1s |
| Non-stability (change per year) | 0.2% |
| Non-linearity | 0.3% |
| Zero offset (A and B) | n/a |
| Spectral range | 300-1130nm |
| Temperature response (-10 °C - +40 °C) | 0.5% (on-board temp. correction) |
| Latitude capability | -90º to +90º |
Global Horizontal Irradiance
| ISO 9060:2018 classification (excl. spectral error) | Class B, Fast response |
| Max. spectral error (per ISO9060:2018) | ± 2.1% (± 8.8 W/m2) |
| Measurement range | 0 - 2000 W/m2 |
| Non-stability (change per year) | < 0.2% |
| Non-linearity | < 0.5% |
| Cosine error | < 10 W/m2 |
| Zero offset (A and B) | n/a |
| Spectral range | 300-1300nm |
| Temperature response (-10 °C - +40 °C) | < 1.0% (on-board temp. correction) |
| Tilt response | n/a |
Measurands
| Global horizontal solar irradiance | W/m2 |
| Diffuse horizontal solar irradiance | W/m2 |
| Direct normal solar irradiance (calculated) | W/m2 |
| Sunshine duration | Hrs |
General
| Weight | 1.2 kg |
| Dimensions | 132 x 132 x 110 mm |
| Power supply and use | 12 VDC, <3W |
| Communication | RS-485 Modbus RTU, Direct to PC, serial over ethernet |
| Operating temperature range | -30 to 65 °C |
| Humidity range | 0 to 100% RH |
| Max measurement frequency | 1s |
| Ingress protection rating | IP67 |
| Mounting | Three M4 thru-holes, equally spaced on 130mm circle |
The go-to solution for a wide range of applications.
| Solar resource assessment | The SolarBand-C3 provides accurate and affordable measurements of diffuse and direct irradiance. |
| Solar power plant O&M | Meets ISO requirements for diffuse and direct irradiance data while minimising cost, maintenance and part count. |
| Meteorological research | Collect direct and diffuse irradiance data at remote and hostile sites where reliability and minimum maintenance requirements are paramount. |
| Meteorological networks | The SolarBand-C3’s measurement capabilities and ease of integration make it an ideal sensor for new or upgraded networks. |
How does the SolarBand-C3 work?
The SolarBand-C3 employs three silicon photodiodes mounted beneath quartz diffuses. Two photodiodes measure GHI, while the central photodiode measures DHI. To enable the DHI measurement, the SolarBand-C3 employs a small automated shadowband inside the glass dome that rotates over the course of each day, ensuring that the central photodiode is continuously shaded.
How extensively has the SolarBand-C3 been validated?
The SolarBand-C3 has undergone extensive internal validation testing over the course of 18 months at Spectrafy's on-sun test site in Ottawa Canada.
Why would I choose a SolarBand-C3 over alternative DHI measurement options?
The SolarBand-C3 hits the sweet spot of accuracy, reliability and affordability for DHI measurement. It combines the accuracy of an automated shadowband with the reliability of a fully enclosed system, at a market-leading price.
-3C allows you to do much more than a thermopile pyranometer. As well as providing ISO9060:2018 Class A measurements of global solar irradiance (like a traditional thermopile pyranometer) the SolarSIM-3C also resolves direct and diffuse irradiance data, with no additional hardware required. This makes the SolarSIM-3C a compelling option for when diffuse and/or direct irradiance data is required in addition to GHI.
How is the SolarBand-C3 calibrated?
All SolarBand-C3 production units undergo electrical, thermal and optical calibration. The optical calibration is performed on-sun against our reference SolarBand-C3 sensors The reference sensors are calibrated for absolute irradiance against thermopile pyranometers traceable to the WRR. The DHI sensor of the SolarBand-C3 is calibrated under diffuse horizontal irradiance. The GHI sensors on the SolarBand-C3 are calibrated under global normal irradiance.
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 SolarBand-C3 measurements.
How do I connect a SolarBand-C3 to my datalogger?
The SolarSIM-3C communicates via RS-485 Modbus. As such it can connect to any datalogger that accepts RS-485 inputs. The Modbus Register Map can be found in the SolarBand-C3 download section.
How often should I get my SolarBand-C3 recalibrated?
We recommend recalibration every two years in order to ensure the highest measurement accuracy. Recalibration can be performed at Spectrafy HQ in Ottawa, Canada, or at qualified third-party calibration labs. Please contact us prior to shipping your unit in order to ensure the swiftest calibration process possible.
Combox
The Combox is a power and comms converter that allows the user to connect to and power their SolarSIM and SolarBand-C3 sensors directly through a PC or laptop.
MP-D2 Mounting Plate
We offer a range of standard, anodized aluminum mounting plates suitable for mounting the SolarSIM-D2 to various solar trackers. Also compatible with the SolarSIM-G, SolarSIM-GPV, SolarSIM-GUV and SolarBand-C3. Custom options are also available.
MP-G Mounting Plate
We offer a range of standard, anodized aluminum mounting plates suitable for mounting the SolarSIM-G, SolarSIM-GPV, SolarSIM-GUV and SolarBand-C3. Custom options are also available.
TMP-G Tripod Mounting Platform
Our tripod mounting platform with integrated mounting plate, provides a rugged, easily installed solution for deploying your SolarSIM-G, SolarSIM-GPV, SolarSIM-GUV and SolarBand-C3 sensor in the field.
Data loggers
Spectrafy offers a range of third-party dataloggers preconfigured with the data logger code required to interact with the SolarSIM and SolarBand sensors.
