Maybe I missed it but does the ability to put 12 lithiums in our SM Redline models solve the high amp problem?? In theory the 4 extra 31 series provide 50% more amp capacity.
Somewhat related. On our Santorin we had a 250 amp fuse for everything coming out of the 12V battery bank (ABYC requirement at the time). It was installed in 2003....Blue Sea, probably slow burn but we never had an incident in 10 years of operation. I think the bowthruster was also rated 10 hp (correct me if this is wrong) so probably drew some high amps at 12V.
I've posted this before but in about 75%+ of our bow thruster manoeuvring we are not in gear and have a habit of high idling our 175amp-24V Leece-Neville--probably feeds a minimum or 75amps into the system and helps to keep the voltage up. Only problem is that people who might be helping you dock can panic if they think that you are in gear. Also have to pay attention to the salt water spitting out from the engine. Also, I am guessing that most of us do this, but we also are at high idle when we use the windlass--whenever we are coasting or doing the final vertical anchor pull.
Bob and Suzanne,
KAIMI SM429 2004 Redline
Emeritus BRITTANY DE LA MER SN86