Planned Electrical Work
The electrical work planned for 2020 can be summarized in the two words "complete rewire". The decision to completely rewire the boat came after tracing the original wire and noting the poor quality of the wiring and bad wire routing choices.
Original Wiring
After considering a partial rewire it became clear that some of the original wire would remain, some would be removed, and accomodating new wiring in the old circuit panel was close to hopeless.
Diesel related wiring
With the removal of the diesel engine quite a bit of electrical wiring is no longer needed. This includes key switch, temperature sensor, diesel tank level, and tachometer. Since the house batteries are being moved and no longer located aft of the engine, these original wires will also be removed.
Engine driven refrigeration wiring
It appears that the engine driven refrigeration was added by a previous owner. This is likely to have been contracted to a professional as it was well done. Regardless the refrigeration wiring differs for a modern electrical refrigeration system. This wiring was also removed early in the process.
Original battery and charging wiring
The original house battery bank is a single 12V 125AH AGM deep cycle battery. In addition there is a 12V starter battery. Both of these batteries have already been removed. The original house bank was charged by the alternator and trickle charged by a 100W solar panel. A Xantrax Echo charger was used to provide charging for the starter battery.
Wires for the original solar charger and battery monitor have been be removed. The battery monitor will be replaced with a set of shunts for charging and load on the 48V, 24V, and 12V banks. The original solar charge controller will also be replaced as it is a PWM controller rather than MPPT. There may be no use for the original Xantrex Echo Charger that isolates the two original 12V batteries.
Original instrument wiring
The original depth and speed instruments were all Datamarine models that were likely installed at build time. The depth instrument was analog with old and corroded coax cables to the transducer. The speed instrument had a clicker style knotlog installed in the navigation station. The wind instrument was also Datamarine and added later, but still very old. The radar was an ancient Furuno with CRT display. None of these intruments are networked since most were early 1980s vintage.
The wind instrument and tachometer were in a terrible location, on the forward wall of the cockpit footwell. If anyone were sitting or standing in the cockpit their legs would obscure visibility. This also seems to be a bad place to put holes in the cockpit.
The GPS was a Garmin 182C, a portable unit mounted when needed to the steering pedestal bars. This is a poor solution for this size boat and while perhaps the most recent instrument is also not capable of networking.
A decision was made to replace all of the original instruments and so with them the wiring.
Original wiring routing and quality
Many of the original wires were run down the center of the engine compartment, through the bilge, and either further aft or under the cabin sole to either side near the aft end of the water tanks. This put electrical wire in the bilge and tie wrapped to the fresh water lines. Even AC wires were routed through the bilge.
On the port side there are very good alternative wiring routes along the cabin sides behind cabinetry. On the starboard side wire routing is a bit more difficult due to the navigation station. Small load wiring can be run in the space above the cabinetry and below the side decks. This might be tight for high load wires but fine for smaller low load wires.
The manufacturers wiring quality was poor. Wire sizes were small. Many wires are duplex with red and black inside a grey cover with some red and brown in a white cover. None of the wires are marked. In many places wires were bundled with what seems to be masking tape or some other paper based tape which had long ago deteriorated.
Most of the previous owners wiring was worse. The VHF was tied directly to the battery. Wire nuts and electrical tape were used to connect wires including AC wiring. AC wiring added by a previous owner used household NM-B solid conductor wire. DC wiring added by a previous owner was often spliced into an unrelated existing pair of wires.
The wires on the circuit panel were soldered on. The circuit panel also had the 12V dual battery switch. Replacing the panel has become a priority due to the unworkable spagetti wiring and use of 24V and 12V battery banks and use of battery protectors.
Gas locker solenoid and stove wiring
The decision to replace the gas stove makes the wiring associated with the gas locker solenoid no longer needed.
New Wiring
This section provides a broad overview of the electrical system. References are provided to other web pages that provide details on the various components of the electrical system and their installation.
Battery Banks
There will be two new house battery banks, a 24V and a 12V bank. The 24V battery bank will serve all high current load, except any that are only available in 12V. The 12V battery bank will handle the cabin load such as lighting, as well as NAV lighting, anchor light, and instruments. The autopilot and replacement radar likely to be 24V loads. Where possible, pumps will be 24V. Refrigeration will be 24V. Any inverter needed for AC/heat or other 120VAC loads will be 24V. If possbile the water heaters will be 24V.
A 48V battery bank will support the electric auxilliary. When an electric stove is added the 48V bank will also support the powerful inverter needed for the stove.
The selection of batteries is described in the Batteries web page. Each of the three banks will be wired as modules with two batteries per module. This is described in detail in the Battery installation Plan web page.
Charging
Charging is expected to be entirely from renewable sources with few if any exceptions. The Battery Charging Plans web page provides an overview of charging plans and links to pages related to charging sources and electronics to monitor and protect batteries. The web page and Wind Generator Mounting web page describe the mounting and wiring of these renewable energy sources.
The Charge Controllers web page describes the charge controllers used for the solar panels, the charge controllers used to charge the smaller batteries, and the related electronics that monitors battery voltages and charge and load currents and power.
The Battery Monitoring and Protection web page describes the electronics to monitor and protect batteries including long term data logging of the battery voltages and the charge and load currents.
The Shore Power AC Charging subsection of the Battery and Electrical Wiring web page describes the shore power charger. The shore charger is installed for the rare occasion when a difficult harbor entrance or canal transit depletes the 48V battery or weather requires extended use of the AC/heat, most likely heat.
Wiring
The current electrical panel is a very old design. It is 17" high by 10" wide, which is an odd size. A new electrical panel enclosure will be made with similar dimensions. It will have multiple 6-8 breaker panels for 12V and 24V loads and various priority loads.
Wiring is described in detail in the Battery and Electrical Wiring web page. This web page has five major sections. The Battery Charge and Load Wiring section covers the high amperage wiring and high amperage discrete circuit breakers, solenoids, shunts, and charge controllers for the 24V and 12V batteries. The Electrical Panel and Breakers and Fuses section describes the electrical panel enclosure and wiring, inverters, and cabin wiring. The Inverters section describes the multiple inverters that will be installed to keep AC wiring to a minimum. The Cabin Wiring section described the overall routing of wiring to the loads in the cabin. The Grounding and Bonding section covers issues of marine grounding and bonding and describes the approach being used.
Loads
The largest electrical load is the electric auxilliary propulsion. The Electric Auxilliary Propulsion web page describes the options considered and the selection of a motor. The Electric Auxilliary Installation web page describes the mechanical and electrical installation of the motor.
An Electric stove will be added later. This will require nearly 5kW of 115V or 230V power provided by a dedicated inverter. A 48V inverter of this capacity would draw 100A with all burners running and the stove running. This is an unlikely case but the inverter should be sized for it. Daily duty cycle is small so this load on the batteries will be less than the electric auxilliary.
The Instrument, Radar, and SSB web page describes the removal of all existing instruments and their replacement. A multifunction display will be mounted on the steering pedestal bars. The Steering Pedestal Changes describes the changes to the steering pedestal bars and the binnacle assembly.
The Autopilots web page describes the autopilot systems considered.
The Electric Refrigeration web page describes heat loss and power draw considerations and the preliminary selection of a refrigeration system.
The Air Conditioning and Heat web page describes the selection of a heat pump unit for air AC/heat. This page also contains some notes on spaces to locate this unit and some of the tank space under the v-berth.
If the windlass is replaced with a 24V electric, this will likely require and 80A breaker. It will require heavy cables to the bow. Wire in the range of AWG #6 to AWG #2 gauge will likely be used.