The PMA2132   Quantum analog Photosynthetically Active light sensor measures the photon flux in wavelength range from 400 to 700 nm. The PMA1132 has a water-proof enclosure and can operate outdoors or in a wet environment. There is a proportional relationship between the number of photons absorbed in 400 to 700 nm band and the rate of photosynthesis in plants.

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U.S.Pat.5,946,641

U.S.Pat.5,790,432

FEATURES

• High sensitivity
• Wide dynamic range
• Excellent long term stability
• Cosine corrected
• NIST traceable calibration
• Hermetic enclosure
  

APPLICATIONS

• Agriculture
• Photobiology
• Meteorology and climatology
• Environmental monitoring
• Educational

> Underwater UVA Detector available

> Wiring Diagram

The energy of a photon is proportional to its frequency and therefore inversely proportional to wavelength. In order to produce a signal proportional to the photon flux (number of photons per unit of area per second) the sensor’s spectral power response (in Amps/[W/cm²]) must be inversely proportional to the photon’s
frequency and therefore proportional to wavelength. Traditionally the quantum flux is measured in micro-moles (also called micro-Einsteins) per second per square meter. The conversion factor is:

1µE/s/m² = 1µmole/s/m² = 6.02*10¹⁷ quanta/s/m²

The angular response of the PMA1132 analog sensor is cosine corrected and suitable for measurements of diffuse radiation or radiation from extended sources.

Specifications

• Spectral response Quantum response (400-700nm) Figure 1
• Angular response 5% for angles <80°
• Range 20,000 uEinsteins/second/m²
• Display resolution 0.1 uEinsteins/second/m²
• Operating environment -40 to 120°F (-40 to +50°C) outdoors
• Temperature coefficient <0.15%/°C
• Cable 50ft (15m)
• Diameter 1.6" (40.6 mm)
• Height 1.8" (45.8 mm)
• Weight 7.1 oz. (200 grams)
  

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