Boats, both power and sail, that have 110V need Shore Cords to plug into marine power at the dock. Some use one while others need two cords.
Shore cords are designed for marine use where water and hydro are in such close proximity.
Domestic extension cords are not approved for marine use and could actually be dangerous. Like everything else marine, you have to know how to use, store and care for your cords.
It’s easy, right? You just plug in both ends and you’re good to go. But, which end do you plug in first?
Think of your shore cord as a water hose. The only way to turn off the water flow is at the dock end first. You wouldn’t disconnect the water hose from the boat first, because the water would continue to flow.
Similarly, you shouldn’t disconnect the boat end of the shore cord first, because it is still alive and could potentially kill someone if it landed in a puddle or fell in the harbour.
So, when leaving the dock, always unplug the dock/shore end first.
NEVER LEAVE A LIVE SHORE CORD ON THE DOCK.
When arriving at the dock, plug in the boat end first, then the dock end. If you do it the other way around, you, could be electrocuted if you accidentally drop the live Shore Cord in the water or grab the end of the cord with wet hands.
You wouldn’t connect the dock end of your water hose first and turn it on before connecting to the boat.
Similarly, you shouldn’t connect the dock end of the power cord first, then handle and connect a live wire to your boat.
Always plug in the boat end first, then plug into the Power on the dock.
See: Shore Up Your Cords
Also see recent article "Faulty Wiring - Man and Dog Electrocuted at Marina" July 17, 2013
Also see another recent article "Kids dying of electric shock drowning" July 17, 2013