OTT PLS - Pressure Level Sensor
Robust ceramic pressure transducer for water level measurement
The OTT PLS measures water level, depth to water, or pressure by means of an integrated controller and ceramic pressure-measuring cell. Design features such as multiple communication outputs (SDI-12 or 4 ... 20 mA), stainless steel housing, and a rugged cable make this sensor ideal for monitoring water level in a variety of applications.
- Surface water, Groundwater
- Vented pressure cell
- Water level, Pressure, Temperature
- Water level and temperature measurement - for use with external data logger
- 0 … 4, 10, 20, 40, and 100 m
- ± 0.05% FS
- No
- SDI-12, RS-485 (using SDI-12), or 4 … 20 mA
- The robust ceramic pressure cell offers industry-leading accuracy and does not deform over time like membrane technology, providing long-term measurement stability
- Rugged design: Ceramic pressure cell resistant to physical force (5 x burst pressure) and enclosure made of high-quality saltwater resistant steel for use in coastal environments
- Built-in microcontroller – compensates for temperature effects and applies correction values for gravitational acceleration and water density
- Vented pressure probe, automatically compensates for changes in barometric pressure
- Robust cable with Kevlar core for length stabilization and capillary tube for venting
- Simple setup and connection to external dataloggers using SDI-12 or 4 ... 20 mA interfaces
- Optimized resolution is achieved by assigning the 4 ... 20 mA to that part of the measuring range that is actually required
- Water temperature output in addition to water level (for SDI-12 output)
Measuring water level in surface and groundwater, including:
- Stations with sloping bottom, e.g. water banks
- Small diameter pipes or holes (from 1" Ø)
- Dams, weirs, irrigation systems
- Waterways that occasionally ice over
- Brackish water, saltwater
- Waterways that do not contain water throughout the year (e.g. retaining basins)
| Water level measurement | |
| Measurement range | 0 ... 4 m, 10 m, 20 m, 40 m, 100 m |
| Accuracy | |
| SDI-12 | ±0.05 % FS (linearity and hysteresis) |
| 4 ... 20 mA | ±0.1 % FS (linearity and hysteresis) 10 ppm/°C at 20 °C |
| Resolution (SDI-12) | 0.001 m; 0.1 cm; 0.01 ft; 0.1 mbar; 0.001 psi |
| Temperature compensated working range | -5 °C ... +45 °C (ice-free) |
| Temperature measurement range | -25 °C ... +70 °C (ice-free) |
| Resolution | 0.1 °C / 0.1 °F |
| Accuracy | ±0.5 °C / ±0.9 °F |
| Electrical data | |
| Available interfaces (use as required) | 4 ... 20 mA, SDI-12, RS485 (via SDI-12 protocol) |
| Supply voltage | +9.6 ... +28 V DC, typically 12/24 V DC |
| Power consumption (SDI-12) | |
| Sleep | <600 µA |
| Active | <3.6 mA |
| Pressure sensor | (capacitive pressure sensor) ceramic, temperature compensated, overload safe for up to 5 times the measuring range without permanent mechanical damage |
| Temperature sensor | NTC |
| Dimensions | 195 mm x 22 mm |
| Weight | approx. 0.3 kg |
| Environmental conditions | |
| Operating temperature | -25 ... +70 °C |
| Storage temperature | -40 ... +85 °C |
| Materials | |
| Housing | stainless steel 1.4539 (904L) resistant to sea water |
| Seals | Viton |
| Cable jacket | PUR |
| Protection type | IP68 |
| Mechanical Strength | meets the mechanical shock tests of IEC 68-2-32 |
| EMC limits | CE conformity; EN 61000-4-2/3/4/5/6 and EN 61000-6-3 Class B are adhered to |