SUNA - Model V2 -UV Nitrate Sensor

The SUNA V2 (Submersible Ultraviolet Nitrate Analyzer) is a chemical-free UV nitrate sensor based on the ISUS (In Situ Ultraviolet Spectroscopy) UV nitrate measurement technology developed at MBARI. Satlantic has adapted the technology to develop the SUNA V2 to measure nitrate in increasingly more challenging environments including extremely turbid and high CDOM conditions. With improved optics and built-in logic intelligence, the SUNA V2 measures nitrate with industry leading accuracy and stability over a wide range of environmental conditions, from blue-ocean nitraclines to storm runoff in rivers and streams.

The SUNA V2 is the ultimate solution for real-time nutrient monitoring. Every SUNA V2 now comes with our proven universal real-time nitrate processing algorithm, which has been upgraded to include adaptive sampling intelligence that automatically adjusts for signal strength. Also included in every SUNA V2 is a 10 mm pathlength, a class based nitrate calibration, serial data output and a 500 meter depth rating.
 
In addition to these standard features, a wide range of optional features provide the ability to customize the instrument to meet your specific research and deployment needs.
 
Optional Features

• Reduced 5mm pathlength for high turbidity environments
• Active fouling control
• Internal data logging and scheduling with 2 GB memory
• Full Freshwater & seawater calibrations
• USB communications and data download
• SDI-12 interface

Performance

• Limit of Detection:
• 0.5 μM (FW or SW with T/S correction)
• 2.0 μM (SW 0-40 psu)
• Detection Range:
• 3000 μM (10 mm path length)
• 4000 μM (5 mm path length)
• Accuracy: ± 2 μM (± 0.028 mg/I-N) or ± 10% of reading
• Short-term precision (at 3σ):
• 0.3& μM (FW or SW with T/S correction)
• 2.4 μM (SW 0-40 psu)
• Drift (per hour lamp time):
• 0.3 µM (FW or SW with T/S correction)
• 1.0 µM (SW 0-40 psu)

Turbidity range:

• 625 NTU* (10 mm path length; absent other absorbing species)
• 1250 NTU (5 mm path length; absent other absorbing species)

*Nephelometric Turbidity Units

Optics

• Path Length: 10 mm & 5 mm (high turbidity option)
• Wavelength Range: 190-370 nm
• Lamp Type: Continuous Wave, Deuterium Lamp
• Lamp Lifetime: 900 h

Electrical

• Input Voltage: 8-18 VDC
• Power Consumption: 7.5 W (0.625 A at 12 V) nominal

Mechanical

• Material : Titanium
• Depth Rating:
• 500 m
• Weight (Acetal/ Titanium):
• 5.1 kg
• Displacement:
• 1749 cm3

Calibration

• Methods:
• Seawater
• Freshwater
• Class-based Freshwater
• Correction:
• Real-Time temperature-salinity correction available*  (0-35o C, 0-40 PSU)

* Requires external T/S data.