WL400 Level Sensor (Submersible Pressure Transducer)
The Global Water WL400 Level Sensor is a rugged, submersible pressure transducer engineered for highly accurate water level measurement across a wide range of demanding environments. Each sensor uses a solid-state transducer with a flexible silicon wet/wet diaphragm, encapsulated in a 304L stainless steel housing (approx. 13/16" diameter) and finished with marine-grade epoxy so moisture can never work its way in and cause drift. A stainless steel micro-screen cap keeps silt, mud, and sludge from fouling the sensing element.
The WL400 outputs a two-wire 4–20 mA signal (convertible to 0.5–2.5 VDC across a 125 ohm resistor) that can run up to 3,000 ft to your logging device, so it drops easily into virtually any datalogger, telemetry system, monitor, or display. A vented cable provides automatic barometric pressure compensation, and a dynamic temperature-compensation system holds accuracy across a broad temperature range.
What’s Included
- WL400 submersible pressure transducer with 304L stainless steel housing
- Molded-on, waterproof vented cable in the length you select (barometric compensation built in)
- Integrated temperature measurement output
- Configuration/calibration software
- Quick reference guide and factory calibration
Key Features
- Accuracy of ±0.1% FS (full scale); ±0.2% over a 35°–70°F range
- Wet/wet silicon diaphragm for excellent linearity and very low hysteresis
- 4–20 mA output; signal transmits up to 3,000 ft
- Automatic barometric compensation via vented cable
- Marine-grade epoxy encapsulation and stainless micro-screen cap resist fouling and moisture
- 10–36 VDC supply; operating range −40° to +185°F
- Six pressure/level ranges (0–3, 0–15, 0–30, 0–60, 0–120, 0–250 ft) and cable lengths up to 500 ft
Applications
The WL400 is used for remote monitoring and recording of water level and pressure in a wide variety of settings, including:
- Groundwater level and well-depth monitoring
- Pump tests and aquifer/sludge testing
- Surface water flow, stream and river gauging, irrigation canals
- Tank, tide, and floating-dock level monitoring (including saltwater)
- Stormwater, flood analysis, and run-off studies
- Pipe flow and general water pressure measurement
Configuration Guidance
Select the pressure range that covers the maximum water level change expected for your application (not necessarily the total water depth) — choosing the smallest suitable range yields the best accuracy. Then choose the cable length measured from the top of your logger to the bottom of the sensor. A 25 ft cable is standard; longer cables are available up to 500 ft.
Note: the standard polyurethane cable is not recommended for use with hydrocarbons or high concentrations of chlorine — consider the WL450 Water Level Transmitter for those applications.