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Battery Selector Panel

The new battery selector panel controls power to the House and Engine busses. The panel is mounted at the forward end of the port settee. The house switch selects between the house 1 and house 2 batteries. The engine switch selects either the engine battery or the house bus. This arrangement allows any (or all) of the batteries to be used for engine starting in an emergency. It also minimizes the chance of inadvertantly draining the engine battery.

There are 4 breakers on the panel, of which 3 are currently in use. The breaker to the left has a special cover plate to prevent it from being accidentally turned off. It controls power for the automatic bilge pump circuit and also feeds the memory power to the FM radio. It is powered through a pair of diodes connected directly to the 2 house batteries, bypassing the battery selector switches.

The next breaker, unlabeled in the picture, sends power to the audio amplifier (that our son supplied) so that he could play his 'music' at an appropriate level (for him - and for the rest of the anchorage if he forgets to turn it down.)

The other breaker in use is a 30 amp unit to power the macerator pump on the holding tank. It receives its power from the house bus. There is also a key switch on the macerator pump circuit that is located near the pump under the aft end of the port V berth. To actually pump overboard, the thru-hull must be opened and then both the breaker and the key switch turned on.

I planned to add an AC breaker and a GFCI protected outlet in the blank area to the right for dock side power. At present, the AC shorepower is connected directly to the battery charger and relies on the dock side current protection. This hasn't happened in the 20 odd years we've been sailing since we are rarely on a dock. Other than a small inverter, we do not presently have any AC outlets on board.

The panel is made from 1/8" aluminum cut from an old speed limit sign that had been defaced and consigned to the local dump (aka 'swap shop'). We spray painted it to match the interior. The labeling was printed on transparent self-adhesive label stock on a good laser printer and then cut out and pasted to the panel.

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last modified: February 12, 2021