The Mariner Powertrain is ideally suited for Sailing Vessels up to 10,000 lbs in displacement looking to achieve between 5.5 and 6 knots continuous vessel speed.

The Mariner Powertrain is recommended only for applications requiring a low profile drive.

Voltage:  48 Volts

Maximum Power:   10 KW

Continuous Power:   5 KW

Continuous Current:   100 amps

Motor RPM:  2,100 rpm

Reduction:   Helical Gearbox

Cooling:  Forced Air,  Motor Fan, Intake Fan, Exhaust Fan.    Intake and Exhaust Fan controlled by motor temperature.

Propulsion Battery Bank:   10 Kilowatt Hours, 210 amp hours, 48 volts

Hybrid Charger:   1.4 KW or 1.5 KW or 3 KW

House Battery Bank:   2.5 Kilowatt Hours, 210 amp hours, 12 volts




The Mariner Powertrain Includes:

GFCI Protected Smartplug Shorepower Cord cut to length (up to 50 feet available) with integral GFCI protection molded into shorepower cord:   Protects against shorepower induced corrosion in Salt Water and Electric Shock Drowning in fresh water in the event shorepower cord is kicked into water while energized.



Smartplug Shorepower Inlet:   Larger contact surfaces, with O ring seals.    Better wire attachments for longer life.



North Shore GFCI protected cord between inlet and isolation transformer – A space saving way of providing an over current breaker for ABYC requirements, while providing additional, redundant GFCI protection.    Identical to the Northshore Safety Component installed in the shorepower cord.



Charles Isolation Transformer:  The Charles Isolation Transformer is the Heart of the Shorepower Electrical System.     The Charles Transformer contributes to the Safety, Efficiency and Power of the Powertrain and is the most important component of the AC system.

  1. Isolates your Boat’s grounding system from Shorepower Ground.
  2. Eliminates  Corrosion in Salt Water and Electric Shock Drowning in Fresh Water caused by sharing grounds with the dock and other boats.
  3. Suppresses noise from AC line, and reduces voltage spikes that may be harmful to chargers and other electronic equipment.
  4. Eliminates the need for galvanic isolator or polarity indication.
  5. Provides new source of power so fault currents do not flow through the water, making the electrical system much safer.
  6. Wired to provide split phase 120/240 VAC for chargers to increase charger power by up to 65%.
  7. Enables whole boat GFCI protection by eliminating nuisance tripping of the GFCI breaker caused by line filters.


Electroprop AC Distribution:  Provides Split Phase AC distribution to chargers and house AC supply.    Master RCBO breaker for Ground Fault Protection for Ship side AC power.   Individual breakers for charger(s) and house AC circuits.    Waterproof for reliability and to prevent nuisance tripping of Ground Fault Breakers.   Plastic Enclosure to prevent shock hazards and rusting of components.   Built to last to the highest quality.


3 KW Electroprop Hybrid System with 100 amp House Charging:  Waterproof AC Hybrid System in non-conductive plastic enclosure with heat sink and fans for cooling.    The non-conductive enclosure is necessary for a floating propulsion battery bank (negative is not tied to ground – see below for more info ).    The enclosure housing the charger modules is water proof to marinize for the marine environment.    Heat is conducted through aluminum plates to an aluminum heat sink.   A blow box is mounted under the sealed charger box for two fans to blow air across the heat sink, keeping the charging components cool so high charging outputs can be sustained.

Up to three 1500 watt modules can be housed in charger.   Only two can be run at the same time.    Switch between 3 KW charging for the 48 volt system for AC hybrid operation of fast dock charging,   or 1.5 KW charging for 48 volt system plus 1.5 KW charging for house 12 volt or 24 volt system.


with Electroprop Battery Management System:    The Battery Management System has 5 main purposes

  1.  Monitors the batteries for over voltage and turns chargers off if any individual battery goes over a safety set point, thus preserving the life of the battery.
  2.  Monitors the Batteries for low voltage, or amp hours remaining, and turns off loads when batteries get too low, thus preserving the life of the battery.
  3.  Monitors the amp hours consumed and gives a digital readout of remaining battery capacity
  4.  Balances the battery pack to extend the life of the battery pack
  5.  Provides necessary information so operator can deduce health of battery pack and replace battery pack in time to prevent sailing on an empty battery.



1.4 KW Network Charging System

  •  4 x Mastervolt 25 amp Network Chargers with Temp Sensors
  • New Mastervolt Easy Display for displaying Battery Voltage and Temperatures
  • New E xpert Pro Battery Monitor for displaying 48 volt battery information including remaining battery capacity and time to go

With New Easyview 5 display for displaying individual Battery Voltages


Electroprop Waterproof DC Distribution:   Waterproofing extends the life of components by controlling exposure to moisture.   Insulated, Plastic box with O rings eliminates exposure to current carrying conductors to prevent accidental arcing from metallic tools.    Breaker board has Expert Pro Shunt for current measurement.   All cables come in through waterproof strain reliefs.   1 foot long service loop is required.

Electroprop Motor Breaker:   250 amp

Electroprop Logic Breaker: 5 amp

Electroprop Cooling Fan Breaker:  5 amp

Electroprop Charger Breakers: 1 x 60 amp

Solar Breaker:   10 amp

DC converter Breaker:  10 amp

One Accessory Breaker     Choice of 5,10, 15, 20, 30 and 60 amp breakers

Two Fuses for Battery Management System

Two Fuses for Shunt Measurement

The Electroprop DC distribution panel is capable of distributing up to 18 KW of power to your boat systems.    This is the ultimate marine electric DC power panel.

All Breakers are Double Pole Breakers.   The combination of Ground Fault Monitoring and Double Pole Breakers gives the operator the ability to exactly diagnose the system at sea.   Most issues can therefore be resolved immediately allowing uninterrupted use of the vessel.

All Breakers are rated for charging voltages ( 48 volt batteries charge at 58 volts ) and peak currents experienced by the system.


Electroprop Ground Fault Monitoring of Floating Battery Bank:    Electroprop tests for Insulation Resistance to ground for the entire 48 volt electrical system.  Floating (or  Isolating) the battery pack is how all electric cars are wired, and how any boat from 48 volts to 500 volts are wired.    We use this method because it is safer, easier to understand, easier to monitor.    The propulsion battery bank is not connected to the boats grounds, underwater metals, AC green wire or 12 volt DC negative.   Keeping the Propulsion Battery Independent insures reliable operation of the vessel.

It is simply the best way of building a high energy battery bank.



Victron Solar Charge Controller:    The Victron Solar Charge controller is capable of handling up to 25 amps of charging current in a small form factor with great efficiency and easy setup.   Optionally, this controller can allow remote monitoring of the battery bank either through the internet or on a cell phone.



4 Northstar Thin Plate, Pure Lead, Advanced AGM batteries:   The Best Marine Battery ever made.  

We use Northstar Batteries exclusively in our systems because they are the best marine battery ever made.    The Northstar Battery is the most forgiving, can be discharged completely without failure, can be recharged faster than other AGM batteries, are forgiving to deep discharges, do not have to recharged immediately and can function in Partial State of Charge (PSOC)  for weeks at a time.  The form factor allows four of these batteries to fit within a 2′ x 2′ x 2′ cube easily making there energy density by volume bigger than other battery shapes and sizes.    There are several sizes of Northstar batteries to choose from.   Standard equipment for the Sailor Drivetrain is 4 x 210 amp hour for the propulsion battery and 1 x 210 amp hour for the house battery.

The Northstar battery will last longer, be more reliable and operate more efficiently than any other lead acid battery.   While operating in PSOC, the Northstar efficiency rivals that of Lithium batteries.   More charging energy is captured and stored for longer ranges.

Thanks Northstar for making such a fantastic battery for electric boats!



And 1 Northstar 2.5 KWH House Battery.   Identical to Batteries in Propulsion Bank is included.   Charged By 100 amp x 12 volt Charger in Hybrid System or separate Mastervolt 25 amp charger.


Electroprop Fused Power Rail

All fuses are within 6 inches of the terminals.   All Fuses are Waterproof with Boots.   All Conductors are Insulated by Grey and Black Large Conduit.   Connections for Battery Management System are fused in the Power Rail.

Electroprop Mariner Drive:  

The Electroprop Mariner Drive has been refined through the years to be  efficient, powerful, tough and reliable.

The Permanent Magnet, Double Stator Motor:   The Sailor Drive features a Permanent Magnet AC motor that gets its power from a Sevcon controller which makes AC out of the DC from the battery pack.

The Helical Gearbox:  The helical gearbox is the most efficient method of converting up to 7 KW of propulsion power to thrust.   Low ratios mean lower input rpm which translates into lower input rpm related losses for any given propeller rpm.    Steel on Steel gears are more efficient than belts.    The gearboxes are very low maintenance and can go over 10 years operation in a recreational sailboat before changing the oil.    Synthetic Oil lasts a long, long time.    Ball Bearings are more efficient than tapered roller bearings at providing thrust in this power range.    The motor is very simple to install on the C face adapter that is part of the gearbox.   The cast iron frame is tough and will last a lifetime.    We custom order our gearboxes with Corrosion duty paint specially applied for the marine application.    We have yet to find a gear reduction method that is more efficient than the helical gearbox in power ranges up to 7 KW continuous / 15 KW Peak.  

The Sevcon Controller:   Known in the industry as the toughest, most reliable, most efficient controller.    We simply can’t say enough good things about the Sevcon Controller.   Over the years we have refined the software to maximize efficiency.    Sevcon and the folks that run this company are first rate.   I have visited the Main Headquarters in England and worked extensively with the technicians in Boston to develop the best firmware and settings possible for our application.    Many thanks to Sevcon for a great product and a great team to back it up.  

The Sevcon Clearview Display:   Mounted in the front of the Sailor Drive, the Sevcon Clearview display provides detailed information on the status of the Motor and the Controller, including Motor RPM and Temperature,   Battery Voltage and Current Consumed by the Drive, controller temperature and Operating Status of the Drive system.    We build a drive system to be as reliable as we can, and constantly improve our products, but we can’t predict operating conditions in the marine world including moisture, water or other issues.     For these reasons we like to enable the operator with as much knowledge of the drive system as possible which is the main function of the Clearview display.    Apart from providing all the operating data, the Clearview gives fault management to enable an operator to quickly find any potential issue that might arise in the marine environment.    The Clearview enables the boat owner to troubleshoot the drive system to give the operator the knowledge to bring the boat home safely.   Its important to us that we give you access to information so you can operate the boat to its fullest potential.    The Clearview gives an interface that allows proper sizing of the propeller, proper rpm for the motor, and different acceleration rates to personify the drive to your liking.   The Clearview is mounted in the drive enclosure to protect from the effects of lightning.    The clearview has been custom programmed for Electroprop for Sailboat Propulsion.

Snow Lily Control Panel


Traditional Throttle:   The Mariner Drive includes the traditional throttle or cable actuated Hall Sense Throttle.

Cooling Fans:   A cooling fan is provided that can be mounted anywhere around the motor to prevent heat buildup.    The mariner drive is rated to 5 KW, and ducting for cooling air at this level of power is not as necessary as for higher levels of power.

Electrical Conduit:   Each Mariner Drive comes with 2 inch flexible electrical conduit for mounting the main power cables in.    The conduit screws into the side of the Mariner drive for a solid mounting.    Plastic Conduit is a great way to protect the large power cables feeding the motor.

Lightning Protection:  

The Electroprop Hybrid Energy System includes surge protection which may help to protect the charger.    Since the Mariner Drive is not in an enclosure, it is not fully protected from a lightning strike.     To minimize the effects of lightning, make sure to mount display and throttle as central and low in the boat as possible (without being in the lower, wet part of the cockpit)    Be sure to take other precautions including an adequate down conductor, an adequate lightning plate underwater at base of mast, and tie all lifelines into the grounding system.   A stem to stern central conductor along the lowest most central part of the boat and hooking together the underwater ground plate and rudder shaft is recommended.



The Propeller:

Choose our High Efficiency Propeller (included) which has high pitch, high blade area ratio, and cupping, an optional feathering propeller,  or a propeller credit and source your own propeller.



The Mariner Drivetrain has been engineered to provide the highest levels of safety, efficiency, reliability and power.    Electroprop drives are leading the way for a clean future for sailing on the water, while providing the highest quality of life aboard.



Our standard system includes what we feel to be the ultimate, complete set of components for a safe, reliable, powerful drive system.    By carefully measuring where you mount the various components, we can customize and prefabricate the entire wiring system to minimize installation time.   Various components can be removed or added to the system to make it ideal for your boat or your budget.    We like to work with you and the relationship we forge together, we hope will last a lifetime.   Our customers have enabled and contributed to the developments of the Mariner Drive over the last 10 years and have made our Mariner Drive system one of the only complete systems available today.

Thanks for taking a good look at the Mariner Drive Train.