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Proportional Speed Control Bow & Stern Thrusters: FAQs
What are the advantages of proportional speed control of your thrusters?
There are several, but perhaps most valued is the fact that you can control your docking maneuvers better, applying just the right amount of thrust rather than dealing with all or nothing.
For all those aboard the boat, as well as others across the marina, one of the main advantages is the bow thruster noise level. Operating at full power, on-off thrusters may generate significant noise from the motor and the turbulent water moving in an out of the tunnel.
A third advantage, valued by the captain in particular, is the longer run times that proportional speed control allows. Many on-off thrusters generate quite a bit of heat and if they are run too long, they’ll automatically shut down to prevent overheating, sometimes at inconvenient moments and without any warning.
What’s involved in upgrading to proportional control thrusters?
There are three components to install in a proportional control upgrade, which could be an upgrade to an on-off thruster made by Side-Power or another brand.
The first is a PPC unit, which controls the speed of the motor. The second is the S-Link control circuit, which is a CAN bus allowing full intelligent communication between the components of the thruster system, much like a computer network. The third is the joystick control device used by the operator.
For more info, check out this three-part video series on the upgrade process:
What does the proportional control upgrade cost?
Upgrading an on-off thruster to Sleipner (Side-Power) Proportional Control costs approximately $3000 to $3500 for the equipment per thruster. Labor costs, for changing the control system to S-Link and re-installing the thruster motors, are extra and vary depending on the yard or marina. The upgrade can also be done with the boat in the water.
How common are proportional speed control thrusters?
Since the 2011 introduction of Side-Power’s PPC, more and more builders have offered it as an option on new boats. Back Cove Yachts was one of the first adopters, and they sell more proportional control thrusters than on-off thrusters now. As you’d expect, other thruster manufacturers including Vetus & Quick have recently developed their own versions of variable-speed controllers. In the meantime, Side-Power has filled out its DC-powered product range to the point of offering 140 models that can be offered with PPC controllers.
Do Side-Power proportional controllers have any special features?
Proportional Joystick Controllers (PJC) have LCD screens that track the amount and direction of thrust being generated, plus battery status and run-time. Another popular development is a HOLD function that allows the captain to dock singlehandedly, putting the boat side-to against the dock and then stepping off to handle the dock lines.
For more on bow and stern thrusters, see our story on how to choose the right one for your boat.
Check out this video of Side-Power Proportional bow & stern thrusters installed on a Pavati wake boat:
Bow and Stern Thruster Resources
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