PUV-2500
Profiling Ultraviolet Radiometer 

Biospherical Instruments Inc.  PUV-2500 Profiling Ultraviolet radiometers are battery-powered, submersible radiometers that may be operated as instantaneous profilers of UV radiation and as data loggers - integrating and recording data from all sensor channels at user-defined intervals.  The system has been specifically designed to measure downwelling (cosine) irradiance, pressure/depth, and temperature. Irradiance bands are 305, 313, 320, 340, 380, 395 nm, and PAR (400-700 nm).  Incorporating a custom interference filter with a "solar blind" detector to reduce red-leakage, the 305-nm sensor is designed to respond to the region of the UV-B spectrum strongly affected by atmospheric ozone concentration. Similarly, the 313, 320, 340, and 395 nm detectors incorporate custom interference filters that, in combination with UV-passing/light-blocking filters and sensitive silicon photodiodes, minimize errors associated with spectral leakage.

Key Features

• High speed, very wide dynamic range
• Standard 6 UV wavelengths and PAR downwelling irradiance
• Standard upwelling natural fluorescence radiance channel
• Small, rugged, lightweight, battery-powered
• Hand deployed in lowering frame or free-fall (optional)
• Available with radiometrically matching surface sensor (PUV-2510)
• Individual cosine collector simplifies optical calibrations and is optimized for use underwater (PUV-2500) or in air (PUV-2510)
• Requires just a single COM port for both instruments (PUV-2500 and PUV-2510)

The PUV-2510 was specifically designed as the radiometrically matching surface reference sensor for the PUV-2500 Profiling UV Radiometer. Like the PUV-2500, the PUV-2510 measures downwelling irradiance at 305, 313, 320, 340, 380, 395 nm and PAR (400-700 nm). The design features a Teflon® diffuser and quartz optics to achieve outstanding cosine response in air.

BSI provides PROFILER, a Windows-based data acquisition and analysis software package.  This software allows the host PC to acquire data and display it on a monitor.  The software includes full graphical display with multiple user-selected channels. Data files are recorded in an ACCESS® database format. The profiler package includes user-specified configuration to speed profile setup. 

Specifications
PUV System Electronics Specifications

• Microcontroller: High performance PIC17C756 CMOS microcontroller Featuring 8bit, 18.432MHz frequency, internal 16K non-volatile EEPROM
• Data Acquisition: A high accuracy 16 bit ADC with a PGA input yielding a 10 VFS and 1.3 µV LSB. The microprocessor enables auto zero and gain corrections for the A/D and PGA. A set of internal voltage references are also used in calibrations.   32 channel multiplexer selects analog signals from up to 19 photodetectors, temperature sensors, pressure and tilt/yaw sensors.  Real time data averaging can be selected from 17Hz to 1 hour
• Photodetector Preamps: Each detector is individually amplified by an electrometer grade FET Op Amp with variable gain. The available gains (100,000 V/A, 306 V/A and 1010 V/A) cover 10 decades of light levels with minimum detectable signals of less than 10 femptoAmps.
• System Data Rate: user adjustable with maximum rate of 20 Hz and 57600 Baud
• Channel Sampling Time: scan time is typically 15msec when reading including additional processing time, all heads are synchronized to start scans within 500 µsec ±175 nsec
• Optional Sensors: dual-axis instrument inclinometer

• Standard Wavelengths: 305, 313, 320, 340, 380, 395, PAR, Lu(chl)
• Optional Wavelengths: Consult factory for availability.
• Bandwidth: 10 nm FWHM standard except 305 (controlled by atmospheric ozone cutoff)
• Filter Photodetectors: 7 downwelling irradiance wavelengths standard
• Filter Type: Custom low-fluorescence design , 5 cavity interference filters
• Cosine Collector: Teflon®-covered quartz. 
• Angular Response: ±2% from 0° to 65°; ±10% from 65° to 85°
• Out-of-band Rejection: 1x10^-6
• Typical Saturation: 10⁵ µWcm^-2nm^-1
• Noise Equivalent Irradiance: 10^-5 µWcm^-2nm^-1

• Filter Photodetectors: 1 wavelength standard
• Detectors: Custom 13 mm² silicon photodiodes
• Filter Type: Custom low-fluorescence interference
• Out-of-band Rejection: 1x10^-6
• Typical Saturation: 10³ µWcm^-2nm^-1sr^-1
• Noise Equivalent Radiance: 10-6 µWcm^-2nm^-1sr^-1

• Diameter: 10.2 cm Length: 40.5 cm
• Depth Range: 350 m (recommended max. operating)
• Materials: PET plastic housing; plastic fins (optional); stainless steel lowering frame
• Weight: 3.2 kg in air, near neutral in water (without fins)
• Temperature Rating: -5C to 50C
• Typical Performance: Terminal velocity and attitude within 2 m; free-fall orientation less than 2° tilt

• Optical Specifications match PUV-2500 except optimized for use in air.
• Diameter: 10.2 cm Length: 35.6 cm
• Materials: Aluminum housing
• Weight: 3.4 kg in air
• Temperature Rating: -10C to 50C

• Microprocessor: A separate PIC17C756 CMOS microcontroller is used to translate the high level PC program commands to individual head commands, buffer the high volume of data transmitted from the heads and provide exact timing of data collection between heads
• Cable: 2 m RS-232 serial interface
• Battery Power: Rechargeable 12-V gel cell battery; LED indicator light for low battery voltage
• AC Adapter/Charger: Universal 90-240 VAC, 50-60 Hz
• Output: single COM port for both instruments (PUV-2500 and PUV-2510)

Options

• PUV-2510: Radiometrically Matching Deck Sensor
• PUV-514:  Additional Input for Transmissometer. Includes: bulkhead connector, dummy/selector plug if PUV-2500 is equipped with a PUV-683, and a one-meter interface cable. Note: Transmissometer is not included.
• PUV-515:  Lowering Frame Upgrade to Mount Transmissometer
• PUV-552:  Instrument Inclinometer for the PUV-2510
• PUV-565:  PUV Series Travel Case. Fits PUV-2500 in lowering frame with PUV-2510, deckbox, AC adapter and cables (up to 100 m of underwater cable; molded case with retractable wheels; meets ATA dimension requirements for checked baggage, but full system may exceed 18 kg, depending on cable length.

Related Instruments:

• GUV-2511 Ground-based Ultraviolet Radiometer (alternate surface reference for PUV-2500)

  Click here to download a copy of the PUV brochure (588 KB).