RBRcoda PAR, RBRcoda rad

The RBRcoda PAR and RBRcoda rad instruments (Fig. 7) look identical and share several specifications.

coda par
Fig. 7.    RBRcoda PAR and RBRcoda PAR | deep

The RBRcoda PAR and RBRcoda PAR | deep use the cosine photosynthetically active radiation sensors which can measure light within one hemisphere.

The RBRcoda rad and RBRcoda rad | deep use radiometers measuring narrow-band light with a fixed channel width, available in various 10nm- and 25nm-wide channels. Both centre wavelength and channel width are factory-configured.

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°, ±10% at 61-82°

Azimuth error (water)

±1.5% at 45°

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 400µW/cm²/nm (minimum)

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.

Physical

Parameter Value

Connector

MCBH-6-MP

Communications

RS-232

Housing

Plastic or titanium

Diameter

25mm

Length

~235mm (~270mm with connector)

Weight

170g in air, 40g in water (plastic)
330g in air, 200g in water (Ti)

Depth rating

Up to 1000m (plastic)
Up to 2000m (Ti)

Sampling rate

Up to 16Hz

Power

Parameter Value

Supply voltage

6 to 18V (12V nominal)

Power

77mJ per sample (1Hz or slower)
15mA (180mW) (2Hz or faster)

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

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