The OBS501 is a submersible turbidity probe with active antifouling capabilities for better measurements in biologically active water with both high and low turbidity. It outputs an SDI-12, digitally processed signal that many of our data loggers can measure. The OBS501 is similar to the OBS500, but the OBS501 has better mechanical performance in heavy sediment/sand conditions.
The OBS501 has a unique design with a backscatter sensor for higher turbidity and a sidescatter sensor for lower tubidity. It features a shutter that opens only during measurements to prevent algae buildup.
To avoid sand or sediment wedging, the shutter and body eliminate parallel surfaces between moving parts. A flushing action clears sediment behind the shutter.
For biofouling prevention, it uses the ClearSensor Method (U.S. Patent No. 8,429,952) with a shutter/wiper mechanism and a biocide-dilled chamber. OBS501 is a trademark of Campbell Scientific.
It can detect motor strain and dislodge sand grains if needed. Optional plastic or copper sleeves are available for added protection, especially in sea water.
- Dual backscatter and sidescatter sensors used to measure turbidity
- ClearSensor antifouling method for better measurements in biologically active water
- Shutter/wiper mechanism keeps lenses clean
- Refillable biocide chamber prevents fouling
- Disposable plastic sleeve facilitates cleanup
- Optional copper sleeve for additional protection (especially for sea water) or disposable plastic sleeve facilitates easy cleanup
| Dual Probe | 90° sidescatter and backscatter |
| Measurement Range | 0 to 4000 NTU |
| Active and Passive Antifouling | Shutter, wiper, biocide, copper, optional removable sleeve |
| Accuracy | ±2% of reading or 0.5 NTU (whichever is greater) |
| Operating Temperature Range | 0° to 40°C |
| Storage Temperature Range | 0° to 40°C |
| Temperature Accuracy | ±0.3°C |
| Emitter Wavelength | 850 nm |
| Power Requirements | 9.6 to 18 Vdc |
| Measurement Time | < 10 s |
| Maximum Submersion Depth | 100 m (330 ft) |
| Diameter | 4.8 cm (1.88 in.) |
| Maximum Cable Length |
|
| Length | 27 cm (10.63 in.) |
| Weight | 0.59 kg (1.30 lb) |
Power Consumption |
|
| Quiescent | < 200 µA |
| Measurement | < 40 mA |
| Communication | < 40 mA |
| Active Shutter Motor | < 380 mA |
Outputs |
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| SDI-12 | Version 1.3, 1200 bps |
| RS-232 | 9600 bps, 8 data bits, 1 stop bit, no parity, no flow control |
| Analog | 0 to 5 Vdc |
