Hi Richard,
Your numbers look about right. I've got a Cheoy Lee Bermuda 30 ketch with a full keel and a displacement of a little more than 10,000 lbs.
Here's part of a post from earlier this year where I described my observed performance shortly after getting my conversion up and running. You can read the whole post on the Yahoo group site.
--- beginning of post #17974 Mar 28, 2011 ---
I did another set of performance trials yesterday. I started at 12:00 noon, after the last rain shower passed. The process took about 90 minutes and I covered 6.35nm during the tests. I ran the same process as before, 1 pass in either direction at a particular throttle setting, progressively climbing through 6 settings and then repeat the process descending through the same settings until done. There was some wind by the end of the trials, but that should be offset through the pass in each direction. The results were more consistant than the last trials which had apparent tsunami surge that skewed some of the numbers.
Here's this weeks results:
495W = 3.0kts
1000W = 3.9kts
1500W = 4.5kts
2450W = 5.0kts
3905W = 5.7kts
5165W = 5.9kts
Slightly better at the low end and a little worse at the top end, but fairly close (+/- 0.2kts) to the previous tests....
--- end of post ---
Even though you haven't mentioned it, I'm assuming that you're running a 48V system. Since there are so many different systems at different voltages in use on this group, I find that watts are much more helpful than amp readings for comparing results. My 5.5kW drive from Propulsion Marine is also a 48V system, the amp loads for the chart listed above was roughly 10A, 20A, 30A, 50A, 80A and 106A (full throttle).
Our boats are fairly similar and your performance is pretty close to what I was able to document previously. Congratulations on a successful conversion.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, Richard Mair <fullkeel2000@...> wrote:
>
> I have 2 27 series banks of Lifeline AGMs so 200 amps total. The numbers look too good for me to believe..I was expecting 3.0 kt. at 20 amp draw.. Next run I will have a gps on board and look at what point the tide is at and do a comparison
> Richard
>
>
>
> ________________________________
> From: acsarfkram <acsarfkram@...>
> To: electricboats@yahoogroups.com
> Sent: Sunday, June 12, 2011 10:30:38 PM
> Subject: [Electric Boats] Re: first run
>
>
> Â
> Hi Richard,
>
> Your performance numbers look great for the Alberg 30. What's your battery setup?
>
> Mark
> Santa Cruz
>
> --- In electricboats@yahoogroups.com, Richard Mair <fullkeel2000@> wrote:
> >
> > Apart from going to the dock from the slings Into The Blue had its first unexpected run today..There are high easterly winds coming tonight and that is the only direction that causes a problem for us
> > Had a 2.4 mile run up the Northwest arm (for those who know Halifax NS waters)
> > Â Â Ran up the arm at 20-22 amp draw and was reading a speed of 3.5 knots at about 960 rpm..This is a new speed gauge so Ii do not know how accurate it is as no adjustments made yet. The EY gauge display said I could do this for about 8 hours at the start. Fluctuated between 7.8and 7.5 on the way up..Current was with us and a slight headwind..
> > Â On the way back down I will take some more readings and compare to the GPS speed.The tide will probably be against us at that time..I did try one burst to 56 amps and 4.5 knots..
> > Â After a couple hours the no load battery reading was back to 50.60 volts...So far figures a seem a bit better than anticipated..
> >  Seem pretty good for a 30 foot 9000 lb displacement fullkeel. We could actually talk during the trip
> > Richard Alberg 30 Electric Yacht 100ibl system
> >
>
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