RBRquadrante (quad)

The RBRquadrante four-channel sensor (Fig. 32) supports multiple radiation measurements (combinations of PAR and rad sensors) within the same sensor package and can be integrated into the RBRconcerto3 and RBRmaestro3.

PAR sensors measure intensity of visible light at frequencies associated with photosynthesis. Narrow-band radiometers are available in a variety of wavebands.

The maximum depth rating of the RBRquadrante is 2000m.

rbrquadrante datasheet69
Fig. 32.    RBRquadrante with three narrow-band radiometers and one PAR channel

Optical radiometry

Parameter Value

Dynamic range

>5.5 decades (nominal)

Initial accuracy1

±2%

Linearity

±1%

Operating temperature range

-5°C to 35°C

Cosine response error (water)

±5% at 0-60°C , ±10% at 61-82°C

Azimuth error (water)

±1.5% at 45°C

Out-of-band rejection2

>25dB (typical), OD 2.5

1 RBR calibrates radiometers with NIST traceable references.

2 Out-of-band rejection is wavelength-dependent for narrow-band radiometers.

PAR

Parameter Value

Wavelength range

400nm to 700nm

Full scale range

0 to 5000µmol/m²/s (minimum)

Resolution

±0.010µmol/m²/s

Narrow-band channels

Parameter Value

Centre wavelengths (CWL)1

380 / 413 / 445 / 475 / 488 / 508 / 532 / 560nm

Full width at half-maximum (FWHM)

10nm (25nm for CWL 475nm)

Full scale range

0 to ≥200µW/cm²/nm (full sun)

Resolution2

±0.001µW/cm²/nm

1 Other CWL options within the 300-1100nm range are available upon request. Contact RBR for more information.

2 Resolution is wavelength-dependent for narrow-band radiometers.

Dark offset is internally temperature-compensated.

Calibration equations

PAR

\[\text{PPF}_c=C_0+C_1*C_2*(V+X_0+X_1*(T-X_3)+X_2*(T-X_3)^2)\]

Irradiance

\[Irr_c=C_0+C_1*C_2*(V+X_0+X_1*(T-X_3)+X_2*(T-X_3)^2)\]