1. Althen Sensors
  2. Sensors
  3. Linear position sensors
  4. Linear inductive postion sensors
  5. S125 Submersible linear inductive position sensor

S125 Submersible linear inductive position sensor

Compact and durable submersible sensor for precise linear position feedback in harsh underwater environments.


Key features

  • Sealed to IP68 for 350 bar underwater use
  • Travel range configurable from 5 to 800 mm
  • Infinite resolution and high linearity
  • Compact stainless steel design
  • Multiple output options (voltage, current)
  • Optional spring-return push rod

Performance highlights S125 (Submersible) linear inductive position sensor

The S125 sensor delivers highly accurate linear position feedback using non-contacting inductive technology, eliminating mechanical wear for longer service life. Its robust stainless steel body ensures exceptional performance in subsea and harsh environments up to 350 bar pressure.

Usage conditions

Ideal for underwater applications including ROVs and marine machinery, the S125 performs in temperature ranges of -4°C to +50°C and resists vibration, shock, and electromagnetic interference.

Possible applications

  • Subsea robotics (e.g., ROVs)
  • Offshore oil & gas installations
  • Marine hydraulics and actuators
  • Underwater inspection tools
  • Scientific measurement equipment

Advantages of choosing this product

The S125 offers a space-efficient, rugged solution with configurable stroke lengths and signal outputs. It simplifies integration through axial or radial wet-mate connectors, supports spring-loaded push rod options, and operates maintenance-free due to its wear-free core technology.

Other important features

  • EMC-compliant (EN 61000-6-2, EN 61000-6-3)
  • Frequency response >10kHz (voltage), >300Hz (current)
  • Shock resistance up to 40g
  • Vibration rated at 10g
  • Available with M8 or M12 rod-eye fittings
  • Up to 3500m operating depth

Do you need this sensor for your next project?

Request a no-obligation quote or send us your contact details for a free, no-obligation consultation. Our sales engineers will then contact you within a maximum of 1 to 2 working days.

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Not exactly what you are looking for? We offer standard sensors, but can also help you with sensors adapted for you or a fully customised measurement solution. Contact us for advice or pricing.

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Technical Specifications

Specification Value
Displacement 0-5 mm to 0-800 mm (factory set)
Output options 0.5–4.5V, ±5V, ±10V, 4–20mA (2-/3-wire), 0.5–9.5V
Independent linearity ≤ ±0.25% (up to 450mm), ≤ ±0.5% (over 450mm)
Resolution Infinite
Frequency response >10kHz (voltage), >300Hz (current loop)
Noise < 0.02% FSO
Sealing IP68, 350 bar
Temperature range -4°C to +50°C
Vibration 10g (IEC 68-2-6)
Shock 40g (IEC 68-2-29)
Body material Stainless steel 316
Rod types Captive, non-captive, spring-return
Connector type Wet-mate MC BH-4-M axial/radial with 0.5m molded cable
Output signal type Ratiometric voltage, differential voltage, current loop

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