getting 24 volts from 12 volts for windlass

[superboots]

The existing setup on my boat uses 2 of the three service batteries to provide 24 volts to serve the bow thruster and sheet winches. I don't understand how this is done and I cannot identify the wiring and connections. The windlass is 12 volts. I have the chance to upgrade to a more powerful windlass which would use 24 volts. As the 24 volt supply to the bow thruster is close to the location of the windlass how easy would it be to tap into this supply and what else would I have to change to the circuitry and componets (solenoids) etc.

 

[SHUG]

The good thing about a 24V windlass is that the wiring can be lighter than for a 12V installation.
I had a boat with dual voltage and the systems were completely separate with a 12V and 24V alternators independently feeding a 12v battery bank and pairs of 12v batteries giving 24v.
It sounds reasonable to go for the 24V windlass and, although you could use the 12V solenoid with a 12V supply to the coil only, it might be better to make the whole installation a 24V system.

 

[DaveS]

The existing setup on my boat uses 2 of the three service batteries to provide 24 volts to serve the bow thruster and sheet winches. I don't understand how this is done and I cannot identify the wiring and connections. The windlass is 12 volts. I have the chance to upgrade to a more powerful windlass which would use 24 volts. As the 24 volt supply to the bow thruster is close to the location of the windlass how easy would it be to tap into this supply and what else would I have to change to the circuitry and componets (solenoids) etc.

Points re. lower current / less voltage drop with 24V rather than 12V are all valid. However, IMHO a more fundamental problem is the one I've highlighted in the quote. It is possibly a difference in philosophy, but I would be extremely unhappy about owning a boat with systems that I did not understand. On the day when (not if) there's a fault, how do you know where to begin if you don't know how the system is configured? Is the problem that the cable routes are hidden and cannot be traced visually, or are they visible but not understood? I presume you do have a multimeter; if not buy one and learn how to use it. (Better still, buy several - they're cheap. Every boat / car / home should have one! )

Unless the boat has two completely separate systems, i.e. a 24V battery bank charged by a 24V alternator and a 12V bank charged by a 12V alternator, there are likely to be problems. A "centre tapped" 24V bank can be used to deliver 12V, but the "lower" battery will discharge more quickly than the "upper" which might also give issues when re-charging.

As far as the specific questions re. the control wiring, it might be possible to retain 12V controls switching a 24V power circuit, but some wiring alterations are likely to be needed - probably quite simple, perhaps substituting a new 12V controls feed for the existing connection to the power circuit, or maybe not even that if the circuits are already separate. However you would need to trace out and understand the present configuration, after which it should be fairly obvious.

 

[Cariadco]

Any help???

To get the 24v, the two 12v batteries used, would be wired in series, so there will be a heavy duty switch somewhere that connects the two batteries, as mentioned. The only other way to get 24v from a 12v circuit requires a 'Step-up Converter' unit, which is not a transformer (although it will produce the same result) but an electronic switching circuit using (basically) an Inductor, Capacitor, high power transistors and control circuit.

I suspect the control circuit for the Bowthruster is 12v and the control circuit for the new 24v windlass, will probably be 12v as well (standardisation)

As for usage, then the only unusual occurance would be if you had to use the Bowthruster AND the windlass at the same time. Without knowing more of the data/current demand figures, I suspect the current drawn by both in use, would blow the main 24v fuse.


Regards.

 

[superboots]

Thanks for your replies. I agree one should understand the systems on ones boat and I intend to do so even if it means getting an electrician in to analyse and explain the set up. So far after various tests its still not clear how wiring is configured - its a standard setup used by Bavaria.

 

[Daydreamer]

My guess is that something like this brute has been used