Daylight measurement in climatological and meteorological applications needs a probe that sees light in the same way as the human eye. This photometric probe measures illuminance in lux, with spectral response adapted to the standard photopic curve V(λ), making it suitable for long-term outdoor daylight monitoring.
A solid-state sensor with a dedicated filter provides the photopic response, while the 50 mm dome protects the optical system against weather agents. Cosine-law correction supports accurate illuminance measurement even at low sun elevation, and each luxmeter is individually factory-calibrated using illuminant 'A' according to CIE publication N°69.
Output versions cover both simple and integrated measurement setups. The passive LPPHOT02 provides mV/klux output without power supply, while active versions offer 4…20 mA or 0…1 V, 0…5 V or 0…10 V outputs over the 0…150 klux range. A levelling device and optional mast accessories support correct outdoor installation.
The probe uses a solid-state sensor with a special filter to match the human-eye photopic response.
It measures illuminance as the ratio between luminous flux through a surface and the surface area.
The diffuser and housing geometry provide cosine-corrected response across the viewing range.
LPPHOT02 connects to a millivoltmeter or data acquisition system and does not require power supply.
LPPHOT02AC provides 4…20 mA output, while LPPHOT02AV provides voltage output defined when ordering.
A silica-gel cartridge absorbs humidity in the dome chamber to help prevent internal condensation.
Code: LPPHOT02 [1]
Example: LPPHOT02AV5
[1] Output
Blank = Passive in mV
AC = 4...20 mA, 2-wire
AV1 = 0...1 V
AV5 = 0...5 V
AV = 0...10 V
