CT125 Electric Tunnel Thruster – 48V (122 kgf)

High-Performance Electric Tunnel Thrusters for Motor Yachts & Sailing Yachts

Max Power CT Series Electric Tunnel Thrusters are designed to give you precise, confident control of your yacht in marinas, tight berths and strong crosswinds. From compact units for 17–28 ft boats up to the heavy-duty CT550 AC for superyachts around 150 ft, the CT range covers almost every type of motor yacht and deep-keeled sailing yacht.

Each CT thruster is built around a robust DC motor, patented composite drive leg, hardened spiro-conical gears and purpose-built high-power connections. Most models use maintenance-free composite legs, while the larger units are available with bronze or aluminium legs for extra strength on heavier displacement yachts. Twin-propeller “Duo” versions deliver maximum thrust and equal performance to port and starboard, while keeping noise and vibration low.

Because these thrusters are supplied as complete, engineered systems, they integrate easily with Max Power control panels, joysticks and safety electronics. That means safer docking, less stress on the crew and better control in real-world conditions such as wind, current and limited visibility.

As an official Max Power supplier, Gaelix Marine Service supports you at every stage: from thruster selection and tunnel sizing to electrical design, installation advice and worldwide shipping. Whether you are upgrading an existing boat or specifying equipment for a new build, our team will help you choose the right CT model and configure it correctly for your yacht.

Technical Specifications — Max Power CT Electric Tunnel Thrusters

Performance data is given for thrusters installed at an immersion depth of one tunnel diameter.

For detailed selection help or custom projects, please contact Gaelix Marine Service — we can match the correct CT model to your hull type, windage and operating profile.

Dimensions + Weight

These dimensions help you check available installation space, tunnel size and hull thickness before ordering your thruster.

Dimensional Drawing (A, B, C, D, E)
(use your CT drawing image here — the one you attached)

• A — Overall length of the motor and leg assembly along the tunnel axis

• B — Overall width of the motor housing

• C — Overall height from the bottom of the tunnel to the top of the motor

• D — Tunnel interior diameter (D Ø Interior)

• E — Recommended hull thickness range at the tunnel location

By comparing these values with your available space, you can confirm whether a given CT model will fit your bow or stern position.

How to Choose the Correct Thruster for Your Boat

For every boat owner it is important to choose the correct thrust rating (or relative power), whether it will be a tunnel thruster or a retractable thruster. To simplify the complex calculations behind hull shapes, windage and displacement, Max Power provides selection charts that show which CT models match each boat length and hull type.

When using these charts, there are two key factors (besides boat length) you should consider:

1. Relative size & wind area of your yacht

For a boat of any given length, the side wind area can differ a lot from one design to another. Underwater shape and displacement also vary. Most recreational motor and sailing yachts will fall into one of these categories:

• Cruising

• Fast Cruising

• Super Fast Cruising

Heavier, taller boats with more windage benefit from the higher-power CT models in each size range.

2. Conditions in which you use your boat (thruster force required)

Usage patterns also matter. An expedition yacht on a world cruise will face very different conditions to a picnic boat moored on a sheltered lake. Some owners prefer extra thrust as a safety margin for strong side winds, tight marinas or short-handed crews.

If the length of your boat intersects more than one thruster on the selection chart, your choice should be based on:

• how exposed your home port is,

• how often you berth in strong wind or current,

• and how much safety margin you want when manoeuvring.

If in doubt, Gaelix Marine Service generally recommends selecting the more powerful model within the range shown on the chart — especially for high-windage or heavily loaded cruising yachts.

Installation Notes

Correct installation is essential for getting full performance and long service life from any Max Power CT Electric Tunnel Thruster. We recommend the following guidelines:

• Tunnel position & depth

  • Mount the tunnel as low as the structure safely allows.

  • The tunnel centreline should typically be at least one tunnel diameter below the loaded waterline to minimise cavitation and noise.

  • Avoid placing the tunnel too close to spray rails, chines or strong hull curvature.

• Tunnel length & alignment

  • Keep the tunnel as short and straight as possible — no more than 2 × tunnel diameter in total length.

  • Ensure the tunnel is perfectly perpendicular to the hull centreline, with smooth transitions and fairing on both sides.

• Hull structure

  • Follow the recommended hull thickness (E) for your chosen CT model.

  • In high-load areas or on cored hulls, add local reinforcement rings or laminates around the tunnel.

• Electrical installation

  • Use correctly sized cables and main fuses according to Max Power specifications.

  • Keep cable runs as short as practical to reduce voltage drop.

  • Mount batteries close to the thruster when possible, especially on larger CT125–CT325 systems.

• Controls & protection

  • Use only original Max Power control panels, joysticks and safety modules.

  • Integrate thermal and over-current protection as specified in the installation manual.

For shipyards, refit yards and private owners, Gaelix Marine Service can provide complete installation advice and, if required, on-site support for fitting CT tunnel thrusters correctly.

FAQ — Max Power CT Tunnel Thrusters

1. Is the CT Series suitable for my boat?

The CT Series covers boats from around 17 ft up to 150 ft, with different options for displacement and windage. If you are unsure, send your boat details (length, beam, displacement, hull type) to Gaelix Marine Service and we will recommend the correct model.

2. What are the benefits of the composite drive leg?

The composite drive leg is corrosion-resistant, maintenance-free and lightweight, while still extremely strong. It removes the need for regular oil changes and greatly reduces long-term service costs.

3. When should I choose a 48 V thruster instead of 12/24 V?

48 V CT thrusters (CT125, CT300, CT325) draw less current for the same power, allowing smaller cables, lower losses and longer duty cycles. They are ideal for larger yachts with dedicated 48 V battery banks or hybrid power systems.

4. Can I retrofit a Max Power CT thruster to an existing yacht?

Yes. CT tunnel thrusters are frequently installed during refits. As long as there is suitable structure and access for the tunnel, Gaelix Marine Service can help you specify the right model and plan the installation.

5. What makes the CT550 AC different from the DC models?

The CT550 AC uses a three-phase AC motor (30 kW) with a powerful 4-blade DUO propeller set and a 400 mm tunnel. It is designed for large yachts and small commercial vessels up to about 150 ft that require very high, continuous thrust and robust industrial-grade performance.