Slim-Diameter Submersible Level Transmitter for Tight Boreholes | SLS300F
An ultra-narrow, fully-welded submersible level transmitter engineered specifically for groundwater grids, restrictive deep wells, and tight borehole piezometric pipes.
The SLS300F solves the problem of deploying instrumentation in crowded or small-diameter observation holes where standard 28mm industrial probes inevitably jam. Offering exceptional profile choices down to a slim 16mm or 19mm outer diameter, this piezoresistive transmitter slides effortlessly past tight pump casings and structural restrictions. Built with a rugged, hermetically sealed 316L stainless steel isolation diaphragm, it delivers dynamic, highly precise downhole telemetry over a wide measurement matrix.
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Ultra-Narrow Form Factor: Available in compact 16mm and 19mm diameters, capable of inputting into narrow 20mm pipes.
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Full-Welding Process: Seamless, rugged downhole construction ensuring premium durability and true IP68 hermetic sealing.
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High-Resolution Precision: Features advanced digital linear compensation with standard 0.5% FS accuracy and custom factory calibrations up to 0.1% FS.
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Flexible Digital & Analog Telemetry: Supports standard current loops, voltage outputs, low-power industrial configurations, and high-efficiency digital I²C / RS485 Modbus RTU.
Description
Precision Hydrostatic Measurement for Space-Constrained Ground Telemetry
Managing groundwater tables, draw-down tests, and deep agricultural well grids requires instrumentation that adapts to tight structural restrictions. The SLS300F Series provides highly stable continuous level monitoring based on the exact physical law that static fluid pressure is directly proportional to depth. Utilizing advanced diffused silicon piezoresistive sensing cores, the sensor converts downhole hydrostatic head directly into stable, industrial-standard electrical signals.
Sized Perfectly for Piezometric Tubes and Casing Clearances
Traditional industrial level probes feature a bulky footprint that makes them highly prone to catching on internal well lips or wiring bundles. The SLS300F bypasses this challenge by condensing advanced digital sensor electronics into two streamlined, ultra-slim configurations:
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SLS300F-1 (19 mm Diameter): The optimal low-profile balance for standard observation wells and deep municipal waterworks.
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SLS300F-2 (16 mm Diameter): An ultra-narrow profile specifically optimized to fit tight ≤20 mm structural monitoring pipes, small borehole sleeves, and crowded deep-well environments.
Features
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Ultra-Narrow Form Factor (16mm / 19mm): Engineered specifically to pass into tight 20mm groundwater observation wells and narrow borehole clearances without jamming.
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Full-Welding Process Integrity: Avoids structural mechanical degradation, providing a durable, hermetically sealed downhole device ready for continuous long-term submersion.
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Advanced Noise Resistance & Anti-Surge: Integrated digital circuitry isolates the transmitter from high RFI/EMI interference and electrical spikes, protecting telemetric data lines.
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Wide Power Supply Flexibility: Operates reliably across a broad input voltage span (8–30VDC default), with low-voltage options (3–5VDC) optimized for digital remote RTU grids.
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Custom Downhole Cable Alloys: Configurable with rugged oil-resistant PUR, durable water-grade PE, or chemically inert PTFE jackets to match diverse groundwater chemical profiles.
Specification
| Parameter | Technical Specification |
| Available Diameters |
19mm (Model 300F-1) / 16mm (Model 300F-2) |
| Measuring Ranges |
0–3 m up to 300 mH2O (Gauge pressure standard) |
| Overload Limit |
Variable by range (150% to 300% FS) |
| System Accuracy |
±0.5% FS standard (High-precision ±0.25% or ±0.1% FS optional) |
| Long-Term Stability |
<0.2% FS/year @ 0.5% FS standard |
| Response / Starting Time |
Response time: <= 10ms (Optionally 1ms) / Starting time: 100ms |
| Signal Outputs |
2-wire 4–20mA / 3-wire 0–10V, 0–5V, 0.5–4.5V / Digital I2C or RS485 Modbus |
| Diaphragm Material |
316L Stainless Steel (Optional: Tantalum, Hastelloy C-276, Titanium) |
| Shell Material |
304 Stainless Steel standard (316L or Titanium optional) |
| Cable Jacket Selection |
Heavy-duty Polyurethane (PUR standard), Polyethylene (PE), or PTFE |
| Protection Rating |
IP68 (Hermetically fully-welded waterproof seal) |
FAQ
Q: What is the main advantage of the SLS300F over standard deep-well transmitters?
A: The defining advantage is its physical size. Standard deep-well probes usually feature a 28mm diameter body. The SLS300F series compresses identical premium piezoresistive accuracy into a slim 16mm or 19mm profile, allowing it to bypass internal tight clearances and drop easily into restrictive piezometric tubes.
Q: Is the SLS300F suitable for heavy-silt downhole conditions?
A: For mediums containing high ratios of abrasive silt, mud, or sand, protective filtering measures must be taken at the transmitter head to prevent clogging the pressure ports or scratching the 316L isolation face. If you are dealing with open, highly turbulent surface waters or unmanaged riverbed channels, our sediment-resistant L706 with a porous ceramic shield is the recommended choice.
Q: Can this sensor be used with low-power battery data loggers?
A: Yes. The SLS300F can be customized with a low-voltage 3–5VDC power configuration and direct digital I²C or RS485 outputs. This enables immediate sleep/wake cycling, drastically extending battery life in remote solar or battery-operated telemetry enclosures.
