Friday 12 August 2022

Shore supply

 I have recently started a new project which is to install a shore power supply this will be useful for a number of reasons, the main one is to keep the batteries fully charged in the winter especially when using the heater which I have not got round to yet. I started by installing the connection for the incoming supply in the forward cockpit bulkhead, I used a previous opening which housed the defunct Stowe echo sounder, wherever possible I try to to reuse openings I have an aversion to cutting unnecessary holes in the boat.


Shore power connection

The shore power connection is linked directly to a two way consumer unit with a 30mA RCD, the earth is connected via a galvanic isolator to protect the boats metalwork from any stray currents. It is recommended that the earth for the 240v shore power system is connected to the boats earthing system so that operation of the boats RCD is not reliant on the marina earthing system. However if there are stray earth currents from other boats or the marina pontoons a circuit can be set up which can lead to rapid degradation of the boats anodes and/or under water metalwork. The galvanic isolator is basically a capacitor connected between the marina earth and the boats earth.


Galvanic isolator and consumer unit

The galvanic isolator and the consumer unit are installed in the quarter berth on the aft side of the bulkhead, the galvanic isolator was Sterling Power Products Pro Save A 16 amp unit. I have installed three single unswitched socket outlets one in the forward cabin, one in the aft cabin and one in the saloon, Again these were positioned to cover up redundant holes in the internal moulding although they are in a practical usable position. The sockets are by a company called Berker available from Fearneaux Riddall.


Aft cabin socket


Saloon socket


Forward cabin socket

The large hole in the internal moulding in the aft cabin was the original route for the engine exhaust and will be utilised for the heater outlet in the aft cabin eventually. I have also installed a Sterling Power Products battery charger. I have run out of places to install an object this size so I made a recessed panel, basically a wooden box, and screwed it to tha back of an opening in the longitudinal bulkhead that runs the length of the quarter berth underneath the chart table.


Battery charger 

The shore supply system is largely complete and up and running the final part of the job is to connect the calorifier immersion heater to the system which is next weeks task. I have managed a couple of sailing trips so far as well as the odd day sail, the main aim was to reach Lowestoft but was defeated by the weather on the first attempt but still managed an enjoyable week away in the river Blackwater, the second trip away to the Walton Backwaters was also defeated by the weather after reaching Pyefleet but a plan 'B' back t to Stangate creek and the Medway ensured that all was not lost