Continuous Improvements – Wiring

Continuous Improvements – Wiring

Over the course of developing our electric sailboat propulsion system, numerous design changes and improvements have been developed, tested, and incorporated into the baseline design.

Looking back, we’ve gone though some significant updates of the motor frame, the gear box, the battery pack, and the cockpit computer.  Lots of software updates for the cockpit computer!

Each of these has resulted in significant improvements that has added to the robust solution we use today.

The next update is going into the wire harness.  The wire harness is central to the system, as it literally connects all the parts.  A new version of that harness is being assembled and installed in our test vessel, so that we’re always demonstrating the latest hardware and software that we’re selling.

The battery pack to motor connections are the high current connections.  Our system limits the maximum current from the battery pack, in three separate ways.

  1. In-line marine circuit breaker at the top of the LFP battery, which will trip if an electrical short occurs in the system.
  2. We setup a current limit in the Battery Management System (BMS)
  3. We also setup a current limit in the motor controller, to taper off power to the motor well in advance of any breakers tripping.

The cockpit has five electrical components that are wired to the motor controller and the battery pack.

  1. EVMS Computer System (cockpit touchscreen, typically mounted in an instrument pod)
  2. Key-switch
  3. Forward / Reverse Switch
  4. Throttle knob
  5. Re-generation knob

The part of the wire harness that runs from the motor to the cockpit is setup with three wires with unique weather proof connectors (so they only fit with their correct mate).  A wire diagram details each of these connections.

We use robust connections that meet industry standards, that make installation as simple as possible.

Over current protection is located in the required areas.  Proper wire types and sizes are used throughout the system.

The cockpit console is laid out in a simple and organized way.  While the EVMS computer isn’t needed for the rest of the system to function, it is always on when the key-switch is on.  It provides important information about the state of the system including battery levels, motor power, vessel speed, heading, and more.

Two of the runs in the wire harness can vary significantly, depending on the boat size and where the battery pack is located.  We will build wire harnesses to order, based on some measurements you take (or given your boat information).  We also can consult with you though the boat re-powering project, depending on your interests and needs.

Just ask, we’re here and want to help.


Walt White

Founder and lead systems engineer, working to bring new products to market that make a positive impact to the environment. Our products and services help boats make the switch to battery electric propulsion, harness renewable energy, and solve other challenges involving marine electric propulsion systems.

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