Seakeeper 6 Installation manual
Rev 22 JUNE 2017
OPERATION MANUAL
OPERATION
MANUAL
Product: Document #: Rev:
SEAKEEPER 6 90403 1
SEAKEEPER 6
OPERATION MANUAL
JUNE 2017
Contents:
Section 1 – System Overview
Section 2 – System Operation
Section 3 – Power Failures, Alarms, and Troubleshooting
Section 4 – Maintenance
Section 5 – Warranty, Limit of Liability, Property Rights
Section 6 – Gyro Specs and Summary
44425 PECAN COURT, SUITE 151
CALIFORNIA, MARYLAND, 20619, U.S.A
PHONE: 410-326-1590
FAX: 410-326-1199
E-MAIL: [email protected]
OPERATION
MANUAL
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Section 1: SYSTEM OVERVIEW
1.0 System Overview
The Seakeeper 6 uses gyroscopic principles to reduce boat roll motions in waves and wakes
independent of boat speed. In multiple Seakeeper installations, the Seakeepers operate
independently of each other and therefore this manual only discusses operation of a single unit.
A Seakeeper 6 consists of a Seakeeper assembly, a CAN communications cable, and a
Display. Figure 1 illustrates the interconnection of these components and their interface with
the boat.
FIGURE 1 – SEAKEEPER 6 STABILIZATION SYSTEM COMPONENTS
Technical specifications provided in Section 6 list the power consumption, total weight, and
dimensions of the major components. Gyroscopic principals that apply to boat roll control are
discussed on Seakeeper’s web site at www.seakeeper.com. The Seakeeper web site also
contains videos of Seakeeper operation and videos of several different boats operating in waves
with the Seakeeper on and off. It is recommended that the reader play these videos prior to
reading the remainder of this manual.
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Section 1: SYSTEM OVERVIEW
The Seakeeper’s gimbal angle and the Seakeeper’s rate of rotation about the gimbal axis
(termed precession rate) play an important role in its operation. These parameters are
illustrated in Figure 2. At zero degree gimbal angle, the Seakeeper is vertical; it can precess a
maximum of +/- 60 degrees about this position. The amount of torque that the Seakeeper
exerts on a boat’s hull to counter the wave induced roll is directly proportional to the precession
rate. The further the Seakeeper is from vertical (zero degrees) the lower the anti-roll torque.
The vertical arrows in Figure 2 illustrate the direction of the forces that the Seakeeper exerts on
the boat’s hull to damp roll motion.
FIGURE 2 – SEAKEEPER PRECESSION
Seakeeper precession is actively controlled by an electronic controller and a hydraulic brake
throughout each roll cycle so the Seakeeper supplies the maximum anti-roll torque and does not
make mechanical contact with hard stops that limit the maximum gimbal angle travel to +/- 60o.
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Section 1: SYSTEM OVERVIEW
There is a large torque about the gimbal axis when the Seakeeper is
precessing. Seakeeper cover panels are provided to prevent personnel
or equipment from contacting the Seakeeper while it is in operation.
These covers should not be stood on, or have anything placed on top.
The covers should always be in place during operation. If it is ever
necessary to touch the Seakeeper while the flywheel is spinning, the
Seakeeper must be locked at the display to stop the Seakeeper from
precessing. Seakeeper maintenance should not be attempted unless the
Seakeeper is locked and the flywheel has stopped spinning.
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Section 1: SYSTEM OVERVIEW
1.1 Seakeeper Assembly
The Seakeeper assembly consists of a flywheel housed in a cast aluminum vacuum-tight
enclosure. The flywheel spins about a vertical axis and is supported by upper and lower pairs of
bearings. A DC brushless motor mounted inside the enclosure spins the flywheel at high speed.
The enclosure is fastened to two gimbal shafts that are supported by gimbal bearings on either
side. These shafts establish an athwartship gimbal axis about which the flywheel and enclosure
precess or rotate up to +/- 60 degrees during operation. The gimbal bearings are supported by a
foundation which is attached to the hull structure. This foundation transfers the loads that the
Seakeeper produces to the hull structure.
An active hydraulic brake mechanism is located on the Seakeeper assembly to regulate the
Seakeeper’s precession motions about the gimbal shaft. It includes two hydraulic cylinders and
a hydraulic manifold.
A coolant pump, heat exchanger with reservoir, and thermostat are located near the manifold. A
glycol/water mix is circulated thru a closed loop to the drive box, hydraulic manifold, and the end
caps of the enclosure to remove heat.
FIGURE 3 – SEAKEEPER ASSEMBLY
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Section 1: SYSTEM OVERVIEW
1.2 Display
The display shown below is the user interface to the Seakeeper 6 and should be mounted at the
primary helm station. It is used to start, operate, monitor and shutdown the Seakeeper.
Sensors, alarms and shutdowns are provided to allow unattended operation.
The display provides information in the event of an alarm. Alarms cause precession to stop
(Stabilize Off) and the Seakeeper to start coasting down (Seakeeper Off).
FIGURE 4 – OPERATOR DISPLAY
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Section 1: SYSTEM OVERVIEW
1.3 Drive Box
The Drive Box contains the electronic components that take 110-230 VAC at 50/60 Hz from the
boat’s generator or shore power and supply current to the flywheel motor according to
commands from the Electronic Control Module (ECM). The glycol/water mix that cools the
Seakeeper is also circulated through a cold plate inside the Drive Box to remove heat from high-
power electronic components.
The Drive Box contains high voltage electronics and the
cover should not be removed while the flywheel is spinning
except by an authorized technician. This high voltage exists
even if the flywheel is coasting down and the supply voltage
has been shut off.
FIGURE 5 – DRIVE BOX
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Section 1: SYSTEM OVERVIEW
1.4 Electronic Control Module
The Electronic Control Module (ECM) monitors all the system sensors and automatically
regulates operation of the Seakeeper.
The controller commands the motor speed and regulates the Seakeeper’s precession rate and
gimbal angle. This is accomplished by commands to a high response flow control valve in the
hydraulic brake circuit that increases or decreases the brake pressure.
1.5 Inertia Measurement Unit (IMU)
The motion sensor suite in the IMU contains rate sensors that measure the angular movements
of the vessel and accelerometers that measure the vertical and lateral boat movement. These
signals are communicated to the ECM on a CANbus connection inside the Seakeeper’s wiring
harness.
1.6 Brake
The brake mechanism consists of two hydraulic cylinders that attach to a crank arm on the
Seakeeper gimbal shaft. The Seakeeper controller modulates how fast the oil can flow through
a control valve thus controlling the precession rate of the Seakeeper.
The brake hydraulic circuit is a pre-charged closed loop – that is, there is no pump, motor or
reservoir in the circuit. Accumulators are installed in the circuit so the precharge pressure does
not increase as the fluid temperature rises due to the braking action. Locking solenoids are
installed in the circuit to lock the Seakeeper so it cannot precess during ‘lock’ mode or if there is
a leak in the circuit or a mechanical problem with the Seakeeper.
FIGURE 6 – BRAKE SYSTEM COMPONENTS
Seakeeper hydraulic Hand Pump Kit, P/N 10384, is required for servicing the brake system.
Pressure should never be relieved unless this tool is available.
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Section 1: SYSTEM OVERVIEW
1.7 Cooling
The cooling circuit is a closed loop that supplies a glycol/water (50% distilled water and 50%
glycol) mix to:
The motor drive box to remove heat from the drive electronics
The brake manifold to remove heat from the brake hydraulic circuit
The Seakeeper enclosure water jackets to remove heat from the flywheel bearings
The heated fluid then passes through a thermostat before bypassing or flowing through a heat
exchanger that has sea water on the cold side. The circuit also contains a coolant reservoir for
coolant expansion and to make filling easy. The reservoir contains a 7 psi (0.5 bar) pressure
cap.
FIGURE 7 – COOLING SYSTEM COMPONENTS
Other manuals for 6
2
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