Diffuse solar radiation sensor SRD100

RS485Modbus RTUwith humidity measurement

Overview
The SRD100 is an industrial diffusometer for accurate measurement of diffuse solar radiation, intended for PV performance monitoring and meteorological applications. It is an all-digital, heated sensor that can be used standalone or together with a pyranometer to separate direct and diffuse irradiance components.

Key features

• No moving parts: utilizes a static sensor array and unique shadow mask with a Fibonacci lattice.
• Industry-leading accuracy: fully compliant with IEC61724-1 requirements for Class A monitoring systems.
• Digital connectivity: includes remote diagnostics and supports MODBUS communication over an RS-485 interface.
• Built-in heating: provides dew and frost mitigation for reliable operation in all climates.
• Optimized for PV: delivers high-accuracy measurements, specifically designed for clear sky and partly cloudy conditions that are most relevant for PV applications.
• Can be used as spectrally matched reference device measuring the PV-usable portion of solar radiation.
• Rugged surge protection: integrated industrial-grade surge protection ensures durability under extreme PV power plant conditions, with an optional SPD01 Surge Protection Device available to upgrade to 4 kV.
• Global support network: backed by our worldwide service organization for the lowest total cost of ownership.

Applications

• Diffuse solar irradiance monitoring for photovoltaic (PV) performance monitoring systems
• Solar resource assessment and meteorological monitoring networks
• Long-term monitoring in utility-scale solar plants and harsh outdoor environments

Specifications

• Measurand: Diffuse solar radiation [W/m²]
• Optional measurand: Spectrally matched diffuse solar irradiance [W/m²]
• Standard cable length: 3 m
• Uncertainty of calibration: < ±10 %
• Temperature response (-30 °C to +50 °C): < ±0.4 %
• Operating temperature range: -40 °C to +80 °C
• Ingress protection: IP67
• Power consumption (heated): < 2 W (adjustable)
• Power consumption (unheated): < 0.5 W
• Electrical operating voltage: 8 to 30 VDC
• RS-485 isolation voltage: 1.5 kV
• Internal relative humidity: < 40 %
• Recommended calibration interval: < 2 years
• Earthing terminal: Included

Cable length options

• No cable
• 3 m
• 5 m
• 10 m
• 20 m