5. Overview
The CS310 quantum sensor measures photosynthetically active radiation (PAR) in the 389 to
692 nm waveband. The unit of measurement is micromoles per second per square met
re
(µmol/m
2
/s). The CS310 can accurately measure PPFD from 0 to 4000 μmo/m
2
/s, which is a
voltage range of 0 to 40 mV. In practice, the maximum PPFD in the field is about 2500 μmo/m
2
/s,
so the practical (expected) voltage range is 0 to 25 mV.
The quantum sensor is designed to measure PAR received on a plane surface. The indicated
sensor response (
(p. 5)) is selected because it approximates the photosynthetic
response of plants for which data is available. A silicon photodiode with an enhanced response in
the visible wavelengths is used as the sensor. A visible band pass interference filter in
combination with colo
u
red glass filters is mounted in a cosine corrected head.
Measuring PAR within plant canopies, greenhouses, controlled environment chambers, confined
laboratory conditions, or at remote environmental monitoring sites are all typical applications for
this sensor.
During the night, the CS310 may output a slightly negative value, caused by RF noise. Negative
values may be set to zero in the data logger program.
FIGURE 5-1. CS310 spectral response
CS310 Quantum Sensor
5
