Valeport - Model 308 -Self Recording Current Meter

Sensors

Speed

• Type: Impeller [0.27m pitch x 125mm Ø]
• Range: 0.03 to 5.0 m/s
• Accuracy: <0.15m/s, ±0.004m/s >0.15m/s, ±1.5% reading
• Resolution: 0.001m/s

Direction

• Type: Flux gate compass [± 25° gimbal]
• Range: 0 - 360°
• Accuracy: ± 0.25°
• Resolution: 0.25°

Temperature

• Type: PRT
• Range: -5 to 35°C
• Accuracy: ± 0.02°C
• Resolution: 0.002°C

Conductivity

• Type: Inductive coils
• Range: 0.1 to 60mS/cm
• Accuracy: ± 0.05 ms/cm
• Resolution: 0.003mS/cm

Pressure

• Type: Strain gauge
• Range: 100, 200, 500, 1000 or 2000 dBar
• Accuracy: ± 0.1% FS
• Resolution: 0.005% FS

Derived parameters

• Salinity, Speed of Sound and Density are derived from the Conductivity, Temperature and Pressure readings using industry standard equations

Data Acquisition
The vector average is based on a 5 second period during which impeller counts are measured and a single compass reading is made, and the vector average is built up over the averaging period set. Averaging period is any multiple of 5 seconds, up to a maximum of 30 minutes. For the optional parameters, the sample is taken at the end of each sample period, and averaged over the averaging period. Real time display and memory are updated at the end of each averaging period.

Communications

• RS232: Standard, up to 100m cable, direct to PC
• Digital Standard fit, used by 8008 CDU, this is a 2 wire
• Current Loop: method suitable for real time communications over cable lengths up to 3000m (requires adaptor for PC comms))
• RS485: Option, suitable for communications over cable lengths up to 1500m (factory fit, disables RS232).

Memory

• The Model 308 is fitted with 512kb memory, which will hold over
• 125,000 speed & direction records, or over 50,000 records if CTD is also fitted. An optional 1Mb memory is also available.

Control Display Unit

The Model 308 can be used in real time with Valeport’s Model 8008 Control Display Unit (CDU). This features an LCD graphics display of all parameters and allows full sampling set up of the instrument. The 8008 CDU also has its own internal memory, which can be downloaded to PC in spreadsheet compatible format.

• Power: 8 x 1.5v "C" cells (also powers instrument)
• Size: 244 x 193 x 94mm, 2kg
• Protection: IP67 (10secs @ 0.3m).

Power

• Internal: 7 x 1.5v “C” cells, which last for over 1 year at 10
• minute recording intervals.
• External: 10 - 18vDC, <1W. (May be taken from 8008 CDU).

Physical

• Depth rating: 2000m (Only 1000m if Conductivity fitted)
• Materials: Titanium, 316 Stainless Steel & Acetal and ABS plastic
• Size: 76mmØ x 1080mm
• Weight: 13.5kg
• Suspension: 1000kg
• Shipping: 130 x 30 x 32cm, 27kg

Software

• System is supplied with DataLog Windows based PC software, for instrument setup, data extraction and display of tabular and graphical data plots. DataLog is license free.