HNL70-A Submersible Liquid Level Sensor & Transmitter, IP68

The HNL70-A immersion level sensor uses a high-performance diffused silicon piezoresistive pressure element to measure the liquid static pressure, which is proportional to liquid depth. A signal conditioning circuit converts the pressure into a standard current or voltage output, giving a linear correspondence between output signal and liquid depth. The probe can be immersed directly for long periods; it has special gas-conducting cable, advanced sealing technology and good anti-leakage performance, and is easy to use.

INQUIRY

Hydrostatic Level Measurement for Wells, Tanks and Reservoirs

The transmitter suits petroleum and chemical industry tanks, power plant water and oil systems, urban water supply and distribution, hydrological exploration and monitoring, deep wells and boreholes, reservoirs, rivers and lakes, sewage and wastewater treatment, groundwater monitoring, fire water tanks, irrigation and canal systems, and industrial water and oil tanks.

Good fit: petroleum and chemical tanks, power plant water and oil systems, urban water supply, hydrological exploration and monitoring, deep wells and boreholes, reservoirs, rivers and lakes, sewage and wastewater treatment, groundwater monitoring, fire water tanks, irrigation and canals, industrial water and oil tanks.

Is HNL70-A Suitable for Your Application?

Choose HNL70-A when:

• You need hydrostatic level measurement by immersing the probe in wells, tanks, reservoirs or open channels.

• The control system accepts 4–20 mA two-wire, HART, RS485 or a three-wire voltage output, and a display head is optional.

• You need a sealed stainless probe with IP68 sensor part and IP65 wiring part.

Confirm with us first when: the medium is corrosive to 316 / 0Cr18Ni9 stainless steel, the required range exceeds 200 m, the medium temperature is outside the rated range, or a flange / special process connection is required.

Structure and Features

Split sealed design

Split-type structure: the sensor immersed in liquid is a fully sealed stainless steel assembly; the electronic circuit housing is a cast aluminum part installed at a convenient wiring location. The imported sensor chip has laser resistance compensation for zero point and temperature performance.

Protections and reverse polarity

Multiple protections give good anti-leakage performance and strong anti-interference ability, with reverse power protection. A display head (LED or LCD) can be added on suitable versions.

Element and range options

Diffused silicon, ceramic piezoresistive or ceramic capacitor elements; integrated, split, high-temperature, rod or anti-corrosion versions; range up to 200 m on request.

Technical Specifications

Selection Code

Mechanical Dimensions

Stainless submersible probe connected by vented polyethylene cable to the cast aluminum electronics housing; the housing can carry an LED or LCD display head. Probe length and cable length match the ordered range; rod and anti-corrosion versions follow their own range limits.

Installation and Wiring

Lower the probe to the tank or well bottom so the pressure port faces downward or as specified; keep the vented cable's air path clear to avoid clogging. Mount the housing at a dry, accessible wiring location. Wire the two-wire 4–20 mA loop to the supply and controller; match three-wire voltage and RS485 versions to their respective wiring. Protect the cable against abrasion and floating debris; verify the level reading against a reference after commissioning.

Typical Applications

• Water supply and wells: deep wells, boreholes, reservoirs, rivers and lakes, groundwater monitoring.

• Industry: petroleum and chemical tanks, power plant water and oil systems, industrial water tanks.

• Environment: sewage and wastewater treatment, hydrological exploration and monitoring, irrigation and canals.

• Storage: fire water tanks, dosing and circulation tanks.

What to Send Us for Selection

Send: medium and density, required range, medium temperature, supply voltage, output preference (4–20 mA / HART / RS485 / voltage), display requirement, process connection, and whether the medium is corrosive to stainless steel. We will confirm the element, version and selection code before quoting.

Frequently Asked Questions

Can it measure deep well water levels?

Yes. The immersed probe measures hydrostatic pressure to the liquid surface; diffused silicon versions cover up to 200 m. For deep wells, specify well depth, water level variation and cable length so we match the range and cable.

How does liquid density affect hydrostatic level accuracy?

Hydrostatic pressure equals density × gravity × depth, so level reading follows the actual density. For consistent density (water) the calibration holds; for varying or known non-water density, tell us the density so we can confirm the scaling.

Will corrosive media damage the stainless probe or vented cable?

Standard connectors are 316 / 0Cr18Ni9 stainless steel with polyethylene vented cable. Strong acids, alkalis or solvents may attack these; describe the medium so we can recommend the anti-corrosion version or a suitable element.

Can 4–20 mA output support pump dry-run and overflow control?

Yes. The 4–20 mA loop feeds the controller or pump interlock; combine a level switch or threshold logic for dry-run protection and overflow alarm. HART or RS485 versions add signal and diagnostic access where supported.

What maintenance keeps the pressure port and vent tube unobstructed?

Keep the pressure port free of sludge and scale, and keep the vent tube's air path clear against moisture and dust. Inspect the probe and cable periodically in sewage or dirty service, and clean or replace per the actual fouling condition.

Datasheet Download

HNL70-A Submersible Level Sensor Datasheet (PDF) — view all product manuals on our Download page »

Need a Submersible Level Transmitter?

Send us the medium, density, range and temperature. We will confirm the element, version and selection code before we quote.

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