A/C electrical loads, and a large trawler that is circumnavigating

Here’s a posting on the “comments” page of my website from yesterday:

I think going over to a three phase boat would involve new generators, a new Atlas unit and a major rewire. At the end of the day it would not solve the high start up current problem. Your best solution is converting the airconditioning compressors to a soft start system.

Changing the subject the motor yacht Whalesong made the trip from Dutch Harbour to Japan last year. They only have one sentence on the trip across the Bering Sea (rough) but do give some insight to the problems of getting into Japan. No doubt they could give you further information.

Their site is www.mywhalesong.com

The site is a little flaky when navigating around at the moment, a more dirct link is

http://web.mac.com/jbfoto/WS_Logs/East_Asia/Archive.html

Ted

Ted:

Cruisair makes soft starts that accept single phase input, and control a three phase chiller:

http://www.dometic.com/enie/International/Site/Marine/Cruisair/AC/Products/?productdataid=73677

I’m still deciding what to do, but my current thinking is to replace my four existing chillers with one 3-phase 60,000BTU unit, and one 3-phase 36,000 btu unit, plus two VFD drives. This will essentially give me the possibility to get 36,000BTU, 60,000BTU or 96,000BTU, at approx, 12, 26 or 38 amps respectively of power consumption (plus the 14 amps or so for the sea water pump, chilled water circ pump and air handlers). I’m also looking at swapping the smaller of my two generators, the 16kw, for a 20kw generator. This will give me about 85 amps of power, instead of 66 amps. My “normal” house load, with battery charging, seems to run around 14 amps. If you do the math, to run all 96,000BTUs, with the house load, I’d need around 70 amps. 96,000BTU is less than I have currently (136,000BTU), but I believe it is adequate, and I need to reclaim some space in order to have a place to put the VFDs.

Thank you for the link to Whale Song! That’s a great lead. I would like to contact them, but can’t find any contact info on their website. If you or anyone reading this can find an email address let me know. They are doing roughly the same kind of circumnavigation as we plan, and I’m sure would have some great advice for us.

-Ken W