Perko Dual Battery Selector Switch, Cup Mount

The Perko Dual Battery Selector Switch is a cup-mount switch selecting either battery or both in parallel, with a make-before-break design.

Make-before-break is the specification that protects the alternator, and it is not optional on a boat with one fitted. The switch connects the next position before releasing the last, so the alternator is never left with no battery on it. A break-before-make switch momentarily disconnects the load, and that voltage spike destroys alternator diodes.

Cup mounting sets the switch into a panel rather than standing it proud, which suits a helm or a console face. That is a different installation from the bulkhead-mounted switches in the range, and the cutout has to be made for it.

It selects either battery individually or both in parallel, and can serve as an emergency main disconnect. Both-in-parallel is what gets a boat started on a flat bank, and having that on the main selector avoids a separate emergency parallel switch. Explore more battery switches.

• Make-before-break protects the alternator
• The alternator is never left with no battery on it
• A momentary disconnect destroys the diodes
• Cup mount sets into a panel, not onto a bulkhead