RT1 Rooftop PV Monitoring Sensor
The RT1 is an affordable rooftop solar monitoring sensor that combines a pyranometer and a back-of-panel temperature probe, designed to mount on the corner of a commercial rooftop PV array for plane-of-array irradiance monitoring.
- Range
- 0 to 2000 W/m² (irradiance)
- Output
- RS-485 Modbus
- Supply
- 5 to 30 VDC

Overview
In detail
How it works
Mounted on the corner of a rooftop solar panel, the RT1 measures plane-of-array irradiance alongside back-of-module temperature, letting operators assess a solar array's actual output against its expected output.
Deployment
Commercial-scale rooftop solar arrays are growing rapidly, some reaching the size of small utility-scale solar farms, yet performance monitoring has not always been a priority for them. Installing a full pyranometer such as an SMP6 or SMP10 is often not cost-effective for rooftop arrays, so the RT1 gives operators a lower-cost way to plan panel cleaning and maintenance checks.
Connectivity
An RS-485 Modbus output integrates the RT1 into any SCADA or monitoring system.
Measurement
The sensor delivers ISO 9060 Class C irradiance performance and ±1 °C panel temperature accuracy, calibrated against a traceable reference pyranometer.
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Specifications
Technical specifications
- Range
- 0 to 2000 W/m² (irradiance)
- Resolution
- 1 W/m²
- Spectral range
- 400 to 1100 nm
- Output
- RS-485 Modbus
- Operating temperature
- -40 to +80 °C
- Supply voltage
- 5 to 30 VDC
- PV panel temperature
- -20 to +100 °C, ± 1 °C
- Power consumption
- 60 mW
- Non-linearity
- < 1% (0 to 100 W/m²)
- Calibration
- Against traceable reference pyranometer
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