Fitting Capstan/Windlass to SO32.2

[francisdouglas]

I need to fit an electric windlass to my SO 32.2, because I often sail single-handed and have difficulty in pulling up the anchor if it windy etc.

Has anyone any experience of what make/model to fit and what are the factors to be taken into account?

[Zanshin]

While I can't help regarding how many watts the windlass needs to carry, I will add 2cents worth of talk/questions regarding the electrical supply.

Powering your windlass will take a bit of effort. You will need to have the engine running (above idle) so that the alternator kicks out enough energy so that, coupled with your houe bank, the windlass will work.

Let's assume a 600W windlass. At 12V this is a drain of 50A at the windlass, if one adds in losses due to the cable and other factors you might be draining 60A from the battery under load.

Assuming an 80A alternator which might put out 30A when running at above idle speeds then you will only be draining 30A from your battery bank - that is a lot, but the windlass doesn't run for very long and not all of it at high load.

How many Amp-Hours is your house bank?

Now comes the expensive part - cables. If your batteries are aft then you might have a 30-foot cable run. There are several online calculators, the one I used (12V, 60A, 10m cable run (one-way), 3% loss) recommends using 00AWG or 70mm2. That is going to be 20m (out-and-return) and will be over 300GBP.

[francisdouglas]

Thank you,

That is very useful information about the electrics. My house battery is about 150 AH (2 batteries in parallel).

[Zanshin]

150AH is a good buffer, if the alternator isn't putting out enough power then the battery could deal with a 60-second 60A draw without damage.

My shock with electric projects aboard always came when I neglected to factor in the very thick and expensive cables (and fittings, and tools required to work with these).