How to select a Concens electric actuator for underwater operation? A guide to the new models

Choosing the right electric actuator for underwater operation requires both technical expertise and a thorough understanding of the environment in which the device will function. Concens models, regarded as some of the most reliable actuators for demanding conditions, are used in subsea applications such as underwater drones, drilling platforms, service vessels, and hydrotechnical structures.

If you need long-lasting, safe, and efficient operation of an electric actuator underwater, selecting the right Concens model according to specific criteria is the key to success.

Advantages of Concens electric actuators in underwater applications

con series – compact linear actuators for harsh conditions

The con series is a family of slim, cylindrical linear actuators available in several sizes, suitable for a wide range of loads—from lightweight mechanisms to high-force applications. A common feature of all variants is their narrow, linear housing, making them easy to integrate into profiles, arms, yacht furniture, or structures where every millimeter of space matters.

For water and marine environments, the key features include:

• Harsh Environment (HE) versions – tested for submersion and resistance to high-pressure water jets (IP68/IP69),
• Stainless steel versions (e.g., AISI 316/316L) – used where the actuator operates in contact with seawater, splashes, salt mist, or cleaning agents,
• Wide range of forces and strokes – from small, compact drives for deck mechanisms to powerful actuators for hydrotechnical or offshore applications,
• Adjustable speed and gear ratio options – tailored to the movement profile (fast repositioning, slow adjustment, intermittent or frequent operation).

This makes it possible to select a con actuator for both a lightweight service hatch exposed to rain and splashes, and for structural components that are periodically submerged or operate in direct contact with seawater.

icon series – actuators with integrated controller for intelligent marine systems

The icon series is mechanically based on the same concept as the con actuators (the same slim form, similar dimensions, and force range), but the key difference lies in the integrated control electronics. The actuator housing contains a built-in controller that:

• enables motion control via MODBUS RTU (RS485) or discrete signals,
• allows configuration of speed, acceleration/deceleration ramps, and end positions,
• provides diagnostic data such as current consumption, actuator status, and error reporting.

In marine and underwater applications, this has several practical benefits:

• less external electronics – no need for a separate control unit in an additional enclosure, reducing the number of connections and potential leakage points,
• simplified wiring – mainly power supply and communication cable are required,
• easier diagnostics – service technicians can read actuator status from the master control system without physical access to the drive (which is often difficult underwater or on deck).

Combined with stainless steel construction and high ingress protection, icon actuators perform excellently as “intelligent drives” in marine environments—not only in yacht seat adjustment applications but also in technical systems such as hatches, valves, masts, platforms, and covers requiring both environmental resistance and advanced control.

Material durability and corrosion protection

The materials used in Concens actuators are selected to withstand aggressive marine and subsea conditions. Depending on the series and configuration, they include:

• AISI 316 / 316L stainless steel – used in both housing and piston rod; widely applied in marine and chemical industries due to high resistance to chloride corrosion,
• Coated steel and anodized aluminum – for components not requiring full marine-grade resistance but still exposed to moisture,
• Water-, oil-, and chemical-resistant sealing elastomers,
• Special coatings and housing design to minimize water ingress.

HE (Harsh Environment) versions of the Con35, Con50, and Con60 are tested according to IP68 and IP69 standards, meaning resistance to both submersion (e.g., below 1 meter for 1 hour) and high-pressure water cleaning. These configurations form the basis for subsea, offshore, and direct seawater-contact applications.

Protection of electronic systems is equally important. In integrated solutions (e.g., icon35), the control electronics are enclosed within the actuator housing, and cables are routed through sealed glands, ensuring overall system tightness while maintaining full automation functionality.

Selection criteria for the right model

Determining force and torque underwater

Selecting actuator force for underwater environments differs from land-based applications. Water introduces additional drag, friction, and buoyancy forces. Therefore, the required push/pull force must be carefully calculated, including fluid resistance.

Torque (resulting from the gear ratio converting rotary to linear motion) must also account for environmental resistance. Concens models offer a wide range of gear ratios and motor powers—from lightweight con25 designs to powerful con60 actuators—allowing selection for both laboratory and heavy industrial applications.

Selecting stroke length and speed

The actuator stroke must match the application—whether opening a valve, positioning a manipulator, or regulating flow. Underwater, smooth and uniform motion is essential and often slower than on land due to increased resistance.

Speed should be selected as a compromise: too fast may cause cavitation or dynamic overload, too slow may reduce system efficiency.

New Concens actuators—especially in the icon version—enable precise adjustment of speed and motion profile through the integrated controller. Adjustable acceleration and deceleration ramps help reduce mechanical shocks and minimize stress on seals and guides.

IP ratings and marine certifications

For underwater applications, IP68 is the absolute minimum, ensuring dust-tight protection and full submersion capability. In marine or deep-sea environments, IP69 resistance to high-pressure water jets is recommended, along with additional industry certifications if required.

Concens actuators in HE versions meet IP68/IP69 test requirements, making them compatible with offshore, marine energy, and shipbuilding standards. Selecting the correct protection class and materials ensures durability, compliance, and reduced failure risk.

Practical case study and inspiration

Challenge: seat backrest actuation on an external yacht deck

A Polish yacht furniture manufacturer approached AMG Automatyka to design a drive system for adjusting a seat backrest on an external yacht deck. The requirements were similar to those in many underwater and marine applications:

• direct exposure to seawater, salt mist, and UV radiation,
• fully concealed installation within the seat structure (requiring a very slim linear actuator),
• minimal maintenance requirements due to limited access,
• preference for minimal external control components.

AMG Automatyka solution: ICON35 in stainless steel

Application analysis showed that the optimal solution was the ICON35 compact linear actuator with integrated controller. The proposed configuration included:

• Integrated controller (icon) – eliminated the need for a separate control unit, saving space and reducing potential failure points,
• AISI 316 stainless steel construction – ensured corrosion resistance in marine conditions,
• High ingress protection – suitable for splashes, heavy rain, and periodic flooding,
• Operating temperature range from –20°C to +70°C – aligned with European marine climate conditions.

Result:
The seat gained smooth, precise adjustment, while the drive remained virtually invisible to the user. The solution:

• Meets marine environmental requirements,
• Requires minimal maintenance,
• Operates quietly and energy-efficiently.

Conclusions for designers of underwater and marine systems

The yacht case highlights universal principles applicable to strictly underwater applications:

1. Compact linear construction (as in con/icon families) simplifies integration in confined spaces,
2. Integrated control electronics reduce connectors and corrosion-prone components,
3. Proper material selection (AISI 316/316L) and IP rating (IP68/IP69) directly reduce maintenance costs—especially where access is difficult (under deck, underwater, offshore),
4. Cooperation with an experienced automation partner helps move from a general concept to a verified, application-specific actuator model.

This example demonstrates that Concens actuators—from con25 to con60 and in icon versions—can operate successfully both “on water” and underwater, provided the configuration, materials, and protection class are properly selected.