Re: [Amel Yacht Owners] Re: Overcurrent Protection on Winches, Windlass, and Bowthruster


Thanks Bill!  That's exactly what I wanted to know.

On Mar 21, 2016, at 10:02 AM, Bill Kinney greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:



Since Don has sold Harmonie to me (Thank you Don and Ann!)  I will answer your question.  

The fuses Don installed are on the positive terminal of each 24 volt pair of batteries.  They are 125 Amp fuses which would allow about a 500 amp draw from the battery bank.  Probably one would fail a little below this, since the amp draw from the four 24 volt pairs would likely not be exactly identical, especially at very high draws.

The engine electrical system is protected with a 300 Amp fuse mounted in the same style holder on the engine starting battery.

These fuses are a simple and elegant system for protecting the heaviest wires in the electrical system.

Assuming you take advantage of the full 150% fuse rating over the wire ampacity, a 300 Amp fuse would protect 105 degree C rated wiring down to about 2 AWG (34 mm^2)  Smaller wires would still be a risk if not otherwise protected.  The four parallel 125 amp fuses (500 Amps total) would safely protect wires 2/0 AWG (68 mm^2) or larger.

Bill Kinney
Harmonie, SM #160
Port Canaveral, Florida

On Mar 21, 2016, at 09:12, Kent Robertson karkauai@... [amelyachtowners] <amelyachtowners@...> wrote:

Thanks every one. Don, did you use the 300A fuses ?

On Jan 1, 2016, at 10:30 AM, svharmonie@... [amelyachtowners] <amelyachtowners@...> wrote:


Blue Sea Systems make a fuse holder and fuses which mount directly on the battery.  This is a relatively low cost way of complying with this standard and protecting the larger wiring circuits.  We installed fuses on each pair of batteries in the bank as well as the starting battery.  We have not had a fuse blow in the three years that they have been installed.  This has not caused problems with the thruster or any other equipment.

Don Myers

Harmonie, SM160

Join to automatically receive all group messages.