Bow Thruster 12V or 24V

[geoffr]

We are planning on putting a bow thruster on our Prout Catamaran (single screw) and am wondering if anyone has any experience / recommendations with 12V vs 24V.

Putting aside if a boat is 12V or 24V what are your thoughts on Bow Thruster 12V or 24V.

Geoff.

[bobofthenorth]

Always go with the highest voltage possible - less amps for the same watts. Less amps means smaller cables and less voltage drop. Mine is 48 volts (on a 12 volt boat).

[geoffr]

Bob How are dealing with charging the 24V battery?

thanks,
Geoff.

[bobofthenorth]

48 volts. We have a 48 volt bank (4 x motorcycle batteries) that is charged by a 48 volt charger. I always have 110 volt AC available - genset, shore power or inverter - so I suppose its not the most efficient system but it works well.

[geoffr]

Thanks - I have no AC (except the inverter).. so I need to charge of the alternator or Solar.. both 12V (see my post in the other section )

[swagman]

Hi Geoff,
I think the location of the prop is going to be more relevant to performance than the voltage. A more powerful 24v would be less effective than a 12v if it was closer to the surface.
I suggest you look at the Maxpower thrusters than can be deployed when wanted, and withdrawn into the hull when underway. Getting the prop even a further foot underwater makes all the difference.
We had a 12 v Maxpower on. 46 foot mono and it worked well but better safe than sorry etc, if we could have opted for a 24v I would do so.
Cheers
John

[markpierce]

My 24-volt bow thruster has plenty of power. Doesn't take much to do a 180. I'm fortunate in having an inverter and 110-AC and 24- and 12-volt DC systems.

[Honey Ryder]

i have a 24v vetus thruster that moves my 26 ton steel hull very easily. where are your batteries? how big is the boat? if batteries are aft then you could have a long cable run and with a low voltage set-up your cables will need to be very thick (and expensive). if your batteries are up front then they need to be charged, so maybe use an echo-charger halfway between the engine and your thruster.

[geoffr]

The boat is a 37' single engine cat. The main house bank is about a 40' run (one way electrically). The plan is to put a Thruster battery about 10' away in the center of the boat and use an duo-charge (or similar to match 12->24V) to charge the Thruster battery(ies).

[Seahunter]

Originally Posted by geoffr

Putting aside if a boat is 12V or 24V what are your thoughts on Bow Thruster 12V or 24V.

I'm not sure if you can put it aside as adding a 24V thruster to a 12 Volt system requires the added cost of adding battery(s) (and charging [another thread]) to support a 24V system. We just installed an 8HP 12v thruster that requires 500Amps; so it's a trade off. 24V thrusters are going to more torqier (an advantage to bigger boats) with less HP (less electrical draw) than 12V ones, but if you already have the batteries to support the added load of a thruster on 12V, to me that makes most sense if you're system is 12V.

[Andina Marie]

A 24 volt system with dedicated batteries close to the motor will give better service and end up costing less than running long, heavy gauge cables from the starting or house battery. At running current you can typically lose 5% or more of the power in the cables depending on how much you want to spend.

The 24 volt battery can be charged using just a 10 gauge wire from the 12 volt starting battery by using a Trollbridge24 for under $100.

[geoffr]

All,

thanks for the comments - after sitting back and looking at the complexity vs simplicity, weight (we are a cat so this really matters up front!), costs we have decided to install a 12V thruster.

Geoff

[David M]

The greater the voltage, the less weight is a DC motor for a given horsepower.