Pyranometer for Small-Scale PV Monitoring

LPPYRA-Lite measures global solar irradiance (direct + diffuse) on a flat surface in W/m². This allows you to compare the incoming solar energy with the actual PV power output and to calculate performance indicators such as the performance ratio of your PV system. priggen.com+4

The device is designed for small-scale PV monitoring, i.e. smaller rooftop or commercial PV systems. Typical applications include PV monitoring, energy yield forecasting, simple weather stations, and general solar radiation measurements for climate and agricultural applications.

LPPYRA-Lite is a spectrally flat pyranometer, ISO 9060:2018 class C, and thus complies with the relevant WMO and PV monitoring requirements for entry-level and small PV systems.

Several versions are available:

• LPPYRA-Lite: passive, analogue output in µV/Wm²

• LPPYRA-LiteAC: active 4–20 mA current loop output

• LPPYRA-LiteS: digital RS485 Modbus-RTU interface

• LPPYRA-LiteS12: digital SDI-12 interface
  This makes integration into data loggers, PV monitoring systems, PLCs or weather stations very straightforward.

The passive LPPYRA-Lite version requires no external power supply. The active versions are supplied as follows:

• LPPYRA-LiteAC: 10…28 VDC (4–20 mA loop powered)

• LPPYRA-LiteS: 5…30 VDC

• LPPYRA-LiteS12: 7…30 VDC

The pyranometer is optimised for direct tilted mounting in the plane of the PV modules. For horizontal mounting, optional adapters with integrated levelling device are available. Additional mounting brackets (e.g. LPS40/32, LPS3, LPRING04) and M12 connection cables in different lengths simplify mast or rail installations.

LPPYRA-Lite measures global irradiance from 0…2000 W/m² with a spectral range of typically 300…2800 nm (50% points) and a field of view of 2π sr, as is standard for global irradiance sensors.

The pyranometer is specified for an ambient temperature range of –40…+80 °C, 0…100% RH and has an IP67 protection rating. With a weight of about 150 g and an MTBF of more than 10 years, it is well suited for permanent outdoor installation on PV plants.

Each sensor is delivered with its own individual calibration factor (sensitivity in µV/Wm²) printed on the housing and specified in the documentation. iwa-onlineshop.com+3priggen.com+3priggen.com+3
For long-term PV monitoring, international guidelines and manufacturers typically recommend recalibration intervals of about 1–2 years, depending on standards and operating conditions.

• The passive µV version is connected to a high-resolution analogue or differential input of a data logger.

• The 4–20 mA version is wired into a current loop and read via a standard analogue input.

• The digital versions are integrated via RS485 Modbus-RTU or SDI-12 into PLCs, RTUs or environmental data loggers.
  M12 connectors and optional pre-assembled cables simplify wiring; pin assignments and configuration details can be found in the data sheet and operating manual.