Hubbub

While the boat is fundamentally sound, deferred maintenance had accumulated to the point where several vital systems had become unreliable. Electrical, fresh water, and engine issues all require attention. I decided to tackle electrical first because it is central to all the others.

Electrical issues include:

• Faulty shore power connection that was not originally designed for N. America
• Worn out AC and DC circuit breakers
• Batteries that are poorly located and nearly dead
• Numerous short circuits and no sealed connection (heat shrink) wire terminations

On the bright side, there are plenty of serviceable components including VHF radio, instrumentation, radar, chart plotter, pumps, solar panel, and DC refrigeration. All of these require battery power and the batteries are unmaintainable without steady AC power to the battery charger. The critical path starts with safe, reliable AC shore power that can remain connected while the boat is unattended. This will pave the way for new batteries and proper battery maintenance along with an AC heater to keep the cabin warm and dry during the winter.

After a lot of technical study, information and advice from experienced boaters and service people, and endless review of product brochures, I have a polished plan for refitting the AC electrical system.

AC Schematic

The system begins with a SmartPlug shore power inlet. SmartPlug’s combination of features are a vast improvement over the current shore power connection standard. Better electrical contact, superior weatherproofing, a shape that fits only one way, and thermal shutoff built into the inlet all contribute to a much safer and more convenient shore power connection. It’s a vast improvement over the the current round plugs that have been in use for over 70 years. SmartPlug’s ”dual configuration” cordsets will connect the new inlet to standard shore power terminals found in marinas. We’ll carry both 25′ and 50′ cordsets for choice in size and redundancy.

The inlet will connect by a short run to a 30 amp ELCI cirbuit breaker. This device is literally a life saver and as of 4 months ago is a standard requirement on new boats. Here’s an article that explains why every boat with AC shore power should be equipped with a residual current circuit breaker: A Preventable Dockside Tragedy by Kevin Ritz. Just in case you don’t read Kevin’s article, a word to the wise… never get in the water in a marina or swim near any boat that may be connected to shore power.

The ELCI breaker will be part of a custom panel from Blue Sea Systems. Blue Sea offers a flexible, modular panel system that allows one to select the size of panel and exact components to include. Mine will be a 2 x 2 panel containing the 30 amp ELCI main breaker with reverse polarity indicator, a four position distribution module, an electrical meter, and a more comprehensive systems monitor.

The main breaker will feed the primary of a Charles isolation transformer (IT). An IT provides a safe method for electrically decoupling the boat’s AC system from the shore power system and avoiding most galvanic corrosion. The specific model is 93-ISOG2/8-A, which comes with the cabability of transforming 230 volt (European standard) AC supplies to 120 volt. The electrical meter in the Blue Sea custom panel will show volts, amps, and cycles of the shore power current supplying the transformer primary.

The transformer secondary will feed the four position distribution panel with separate circuits for battery charger, water heater, and two outlets. Volts, amps, and cycles will be monitored by the Blue Sea Vessel Systems Monitor. This device is capable of further monitoring batteries, tanks, and bilge pump activity and triggering an alarm when a value exceeds its acceptable range.

I have two more pieces of homework to complete before diving in. First, the SmartPlug inlet will require cutting a hole in the boat and adding a backing plate for reinforcement and to assure a good seal. I don’t relish the idea of cutting a hole in the boat and want to be sure I know what’s involved before starting.

Second, placement of the isolation transformer may be trickier than I first assumed. The device is less than one foot square, but requires 6 inches on each side for proper cooling. Also, transformers hum and it’s not recommended for installation underneath berths, precisely where I had envisioned putting it.

That’s where the project stands for now. Once the outstanding questions are answered, I’ll be ready to start cutting. Step one will be installing the SmartPlug inlet.

Main information resources:

• Nigel Calder: Boatowner’s Mechanical and Electrical Manual
• Charlie Wing: Boatowner’s Illustrated Electrical Handbook
• Online product brochures
• Cruisersforum.com