Who knew there was so much dock-talk about Seakeeper?! The good, the great, and the wildly untrue. The last of which includes a lot of rumors about shutting down the Seakeeper. Here’s what we’ve heard:
“You have to run power to the boat for like… 4 hours while the Seakeeper shuts down.”
“The flywheel stays spinning for hours, so you have to stay with the boat while it does.”
“You can’t put your boat on a trailer until the Seakeeper’s flywheel stops spinning.”
THE SHORT ANSWER
The Seakeeper should be stopped when stabilization is no longer required. Once the vessel is secured in the slip, the high and low current DC power to the Seakeeper should be switched to the Off position. The Seakeeper will continue to spool down to 0 RPM. No cooling is required during this time. (This comes straight from our Seakeeper 1 Operation Manual. AC-powered units have similar language. You can find Operation Manuals on all units in our Technical Library.)
Even shorter: Turn your Seakeeper off when you’re done for the day, and then turn off the power to your boat once it’s secured. Walk away and enjoy a cold, adult beverage.
THE LONG ANSWER
Newton’s first law states that, if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.
Wait… haven’t you mentioned Newton before? You bet we have. You probably recognize the name from “Newton-meter-seconds,” which is the unit in which angular momentum is measured. Refresh yourself on the importance of angular momentum in measuring the stabilizing power of a Seakeeper.
What if the object is rotating, rather than moving in a straight line? Similarly, Newton’s first law of inertia for rotating systems states that an object or system of objects will maintain its angular momentum unless acted upon by an unbalanced external torque. Remember, Seakeeper’s flywheel spins inside a near-vacuum, and therefore, has very few external forces acting to slow it down. So, it can take a while for the steel mass to go from 9,750 RPMs (like the Seakeeper 1) to 0 RPM.
The good news is, once you’ve powered the Seakeeper down, the motor is off and the hydraulic brake arms have locked the sphere in place. Therefore, the motor is not producing any more heat and the Seakeeper is not exerting any forces. Your Seakeeper is safe to be left alone.
Waiting on your flywheel to stop spinning? Ain’t nobody got time for that.