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Max Power · tunnel thruster · bow or stern
Max Power CT550 (three-phase): specs, price and the boats it fits
It gives 992 lb (450 kgf) of push.
- Haul-out to install
- DIY 2 of 5: wiring prep only
- 3-year warranty
Quick stats
- Thrust 992 lb 450 kgf, Max Power's rating
- Boat length Not published See our sizing below
- Price per lb of thrust Not worked out It needs a price and a thrust figure
- Voltage Not stated Ask the maker before wiring
- Battery Not published Ask the maker before wiring
- Run limit Not published Ask the maker before long use
- To install it Haul-out The boat comes out of the water
- Anodes No US price The parts list names them
About the Max Power CT550 (three-phase)
The CT550 is an AC thruster for large yachts: a 30 kW motor on three-phase power turns four-blade counter-rotating propellers in a 400 mm tube for 992 lb of push. An inverter gives proportional control, so you can ease the bow across rather than jab at it.
It runs from a generator, not a battery bank. Max Power specifies 380 to 420 V three-phase at 50 Hz, and any other supply must match the motor’s nameplate, so confirm your generator with the dealer. There is no published price; the dealer quotes the unit and the electrical work together. See the specs.
Read more
Max Power says the counter-rotating propellers, one left-hand and one right-hand, make it more efficient. The motor alone weighs over 220 kg, so it is designed into a build or a major refit. Warranty: two years, transferable.
Installers will find the wiring figures and dimensions further down. For the rest of Max Power’s line, read the Max Power thruster review.
Where this summary comes from (3 sources, read 12 October 2026)
Will the Max Power CT550 (three-phase) steer your boat?
80 FT TRAWLER · BOW · 15 KT WIND
Every knot figure here is wind speed, not boat speed or current.
On a 80 ft trawler the Max Power CT550 (three-phase) (992 lb) steers her in a 23 knot breeze. Her bow needs about 428 lb from a tunnel to steer her in a 15 knot breeze.
The finder leaves it off her list. It is far more than she needs.
The Max Power CT550 (three-phase) on a trawler, by length
- 25 ft72 kt
- 30 ft61 kt
- 35 ft52 kt
- 40 ft46 kt
- 45 ft41 kt
- 50 ft37 kt
- 55 ft33 kt
- 60 ft30 kt
- 65 ft28 kt
- 70 ft26 kt
- 75 ft24 kt
- 80 ft23 kt
Outlined: the finder does not list it at that length (under 13 kt, far more than she needs, or outside Max Power’s own length range).
- Under 10 kt
- 10 to 15 kt
- 15 to 20 kt: the sweet spot
- Over 20 kt: more than she needs
Prices are the low end of the installed total, from our estimate. For your own boat, drive and installer, the finder prices each unit.
Is it right for your boat?
Every kind of boat it fits, by length
| Boat | Full thrust at 15 knots | Still a fit, in lighter wind |
|---|---|---|
| Pontoon & tritoon | Not listed. A pontoon has no hull body between the logs to bore a tunnel through, and nobody sells one for these boats. | |
| Sailboat | No length. More thrust than the boat needs. | |
| Houseboat | 65 to 80 ft | None |
| Catamaran | No length. More thrust than the boat needs. | |
| Trawler | No length. More thrust than the boat needs. | |
| Motor yacht | No length. More thrust than the boat needs. | |
| Bass & flats | Not listed. Nobody sells a tunnel kit for these hulls, and a bass boat’s shallow planing bow has almost no depth to hold one. | |
| Wake & ski boats | Not listed. Nobody sells a tunnel kit for these hulls. | |
| Express cruiser | No length. More thrust than the boat needs. | |
| Center console | No length. More thrust than the boat needs. | |
The Max Power CT550 (three-phase) against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
The first column is where one unit gives all the thrust the boat needs in 15 knots. The second is where the finder still lists it: the unit steers her in a 13 or 14 knot wind, within 15 percent of the 15 knot breeze this site sizes for. On a boat shorter than the first column’s shortest length, the unit is more than the boat needs.
How we size it
Our figure is the longest boat one unit can steer in a 15 knot wind. It is a range because each kind of boat catches the wind differently.
The table tries the Max Power CT550 (three-phase) on each kind of boat, at every length that kind of boat is built in. The wind is 15 knots and the rules are the finder’s own. A length counts as a fit when the unit gives the thrust that boat needs at the bow. Max Power publishes no boat length, so thrust alone decides.
It is sized for one kind of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the installing. The compare page sets this unit beside others.
What it costs installed
No US dollar price is published for the Max Power CT550 (three-phase), so we build no total for it. The yard’s share of the job is on the cost page.
The sizing and the costs on this page are estimates, for guidance only and without warranty. They are no quote, and nobody has inspected your boat. Check them against the maker’s manual and your yard before you rely on them. Terms of use.
DIY breakdown
DIY levels
- Level 5: Owner install. No yard, no electrician.
- Level 4: You install it, electrician connects. You mount and wire it; a marine electrician makes the final connections.
- Level 3: Split with the yard. The yard does the below-waterline part; you do the wiring.
- Level 2: Wiring prep only. The yard installs the unit and does the hull work; you do the wiring prep.
- Level 1: Yard job. A qualified professional does all of it.
You Yard Electrician. The bar is labor hours; a haul-out is a note.
How we rate DIYYou: 4 to 16 hours Yard: 32 to 70 hours Electrician: 2 to 4 hours Plus a haul-out.
Your part needs:Heavy battery cableCrimping big lugs
Every step, and who does it
- Cut, bond and fair the tunnel; fit the gear leg, motor and propeller Yard 32 to 70 hours The low end is two crew over two days, the job as owners describe it on the forums. The high end rises with boat length between two real billed figures: 32 hours at 35 ft, and the largest invoice we hold, 70 hours at 47 ft.
- Mount the battery box, switch and fuse holder; run and secure the cables You 4 to 16 hours Our estimate. No maker times this step, and a first-time owner is slower than a yard, so the range is wide.
- Final connections at the battery and the motor, load test Electrician 2 to 4 hours Our estimate. Nobody publishes a time for the final connections and test on their own.
A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.
Related videos
One of Max Power’s own videos, from its YouTube channel. They play only when you tap. A maker’s video is its pitch, so take any claim back to the figures on this page.
Know before you buy
What sets this model apart, what it costs to keep, and what to weigh.
Price per pound of thrust
There is no US price to divide by its thrust.
Controls
Delivered without accessories: the fuse, holder and control panel are bought.
- Control panel, on/off dual joystick (bow and stern) (318204), $466.83 at MarineDeal.
- Control panel, on/off single joystick (318202), $232.19 at MarineDeal.
- Control panel, on/off touch panel (318200), $219.91 at MarineDeal.
Anodes
We found its anode in Max Power’s parts list, with no US price. The parts below name it.
They sit below the waterline, so a change means a haul-out or a diver.
Service and warranty
Max Power's website gives 3 years. Its manual gives 2, and 1 more if the warranty is registered within 3 months of installation. Outside pleasure craft it is 6 months. It transfers to the next owner, and the first year covers up to 2 hours of labor in the field.
See Max Power’s warranty Max Power's warranty conditions.Special mentions
Max Power sells it for either end, so it can go at the bow or the stern.
Dealer prices at Fisheries Supply, read 26 October 2026.What to weigh
The boat comes out of the water to install it: it needs a tunnel bore below the waterline.
Max Power publishes no boat length for it. The boat table is our sizing alone.
No US dollar price is published for it, so we can work out no installed cost.
Parts for the Max Power CT550 (three-phase)
See the Max Power CT550 (three-phase) manualSearch for the number as printed here, with no spaces. Prices are each dealer’s on the day shown, before shipping and tax. Check the plate on your motor before you order: some parts change with the tunnel size, the voltage or the year.
For the install what the box leaves you to buy
The manual button above opens it on the maker's site. It has the hull, wiring and fuse figures for this model.
From Max Power’s CT550 AC installation manual, September 2026, read 25 October 2026.
- In the box
- The manual prints no box list. It says the inverter comes with its functions set at the factory.
- Bought separately
- A 24 V DC supply for the proportional joystick, the AC power supply and the tunnel. The manual does not say whether the joystick is in the box.
- Charging
- It runs on the boat's AC power, so there is no thruster battery to charge. The proportional joystick needs a 24 V DC supply.
A yard job adds these parts on top of the unit: $1,189 to $2,130 for the priced ones, at Fisheries Supply’s prices on 30 September 2026 and 26 October 2026. It runs on AC power, so there is no battery, charger or battery cable to buy. The cost page has what every maker says about each part.
Outside the hull replacement parts in the water
Anode
The metal that wears away in the water so the drive does not. Max Power calls it “ANODE”.
Propeller, left hand
The propeller on the drive. Max Power calls it “PROPELLER LH”.
Propeller, right hand
The propeller on the drive. Max Power calls it “PROPELLER RH”.
Seal
It keeps water out of the joint it sits in. Max Power calls it “SEAL 30-62-7”.
Drive leg (complete)
The leg under the motor that turns the propeller. Max Power calls it “DRIVELEG”.
Drive leg gasket (seals the leg to the tunnel)
The leg under the motor that turns the propeller. Max Power calls it “GASKET”.
Inside the boat replacement parts on board
Control panel, on/off dual joystick (bow and stern)
The control at the helm. Max Power calls it “Dual joystick, black (318205 gray)”.
The gray one is 318205.
Control panel, on/off single joystick
The control at the helm. Max Power calls it “Single joystick, black (318203 gray)”.
The gray one is 318203.
Control panel, on/off touch panel
The control at the helm. Max Power calls it “Touch panel, two buttons, black (318201 gray)”.
The gray one is 318201.
Motor drive (inverter)
The electric motor that turns the propeller. Max Power calls it “Inverter”.
Replacement motor
The electric motor that turns the propeller. Max Power calls it “AC induction motor 30Kw 400V 3ph 50Hz 2P”.
No part matches. Try the number without spaces, or the part’s name.
Spare part numbers come from Max Power’s parts pages and manuals. A dealer may sell a part we have not priced. Search for the number.
Other sizes and close alternatives
The other makers listed are the nearest match each makes, of the same style and for the same end, within a quarter of its thrust. The compare page lists every model, and the thruster index lists every model with a page here.
For the yard and the installer
Every published figure, with its source.
Full spec sheet
| Thrust and motor | |
|---|---|
| Thrust | 992 lb (450 kgf) As printed: 450 / 992 (kgf/lbs) |
| Motor | 30 kW |
| Voltage | Not stated |
| Run limit | Not published |
| Installation | |
| Type | Tunnel, fixed mount |
| End of the boat | Bow or stern |
| Tunnel diameter | 400 mm |
| What it does to the hull | Tunnel bore below the waterline |
| Haul-out to install it | Yes |
| Maker’s boat length | Not published |
| Price and ordering | |
| Price | No US price published |
| Part number | 6001384-blade duo counter-rotating, bronze drive leg, 3-phase, 380-420 V 50Hz 3PH |
| Documents | |
| Manual | Installation manual (PDF)on the maker's site |
| The site’s review | Max Power thruster review |
Every published figure the site holds for the Max Power CT550 (three-phase), with where each came from.
The tunnel: length and depth rules
Depth below the waterline. The minimum acceptable position is 139 mm below the waterline. Ideally the top of the installed tunnel sits 185 mm below it. Shallower than the ideal, the manual says, performance falls off progressively. CT100 and CT125 installation manual (July 2024).
Our notes from the manual and listings
In the box: Delivered without accessories: the fuse, holder and control panel are bought.
Our note
A 30 kW unit on 380 to 420 V three-phase at 50 Hz, so it runs from a generator, with four-blade counter-rotating props in a 400 mm tunnel. Max Power publishes no price and sells through dealers. Its Global Network page lists ten in the US.
Where each point above comes from
- Max Power sells it for either end, so it can go at the bow or the stern.The maker's listing
- The boat comes out of the water to install it: it needs a tunnel bore below the waterline.The mounting: a bore through the hull, or a housing recessed into it
- Max Power publishes no boat length for it. The boat table is our sizing alone.The maker's documents, as the database records them
- No US dollar price is published for it, so we can work out no installed cost.The maker and the dealers the database reads
Not sure this is the one? The thruster finder asks about your boat and prices every unit that fits.