Hi Jim,
Did you get my private message?
Mark
Santa Cruz
--- In electricboats@yahoogroups.com, jim_ranger_26 <no_reply@...> wrote:
>
> Hi Mark,
>
> I'm firmly in the first phase of the Six Phases of a Project, namely, "Rampant Enthusiasm". There will be plenty of time to eventually get around to "Depressing Recognition of Reality", "Ensuing Panic", "Search for the Guilty", "Blaming of the Innocent", and "Rewards for the Non-participants" :D
>
> You're absolutely right - I should have said "cruise" instead of "full power" on the sustained runs as, obviously, a lot of sustained full-power use could not only cause cavitation, but, drain the batteries pretty quickly - that's what I get for posting after midnight (now I understand why you don't feed Gremlins after midnight :)
>
> I will definitely take you up on the visit offer - just let me know when good days/times would be via a direct message, and we can narrow it down to something mutually agreeable (my Thursday and Friday afternoons are usually booked, but, everything else is pretty much open).
>
> Thanks, and All the Best,
> Jim
>
>
> --- In electricboats@yahoogroups.com, "acsarfkram" <acsarfkram@> wrote:
> >
> > Hi Jim,
> >
> > You are certainly doing your homework :-).
> >
> > You wrote this in your last post, "I can readily see the sailboat profile consisting of long, full-power runs while motoring in/out of port..." I have found with my EP setup that "full power" is very rarely needed. If you start out with full power you will cavitate the prop and accelerate slower (stating the obvious). I use full throttle when exiting or entering a tricky harbor entrance (think Santa Cruz winter conditions with breaking waves across the harbor mouth). Generally I will accelerate over a few seconds to a 50amp (2500 watt)draw then cut the power to 15-30 amps or cut the power completely and glide. If I used full power in the Harbor I would exceed the 5mph speed limit :-).
> >
> > If you find yourself in Santa Cruz and would like to see my Ericson 27 with a SolidNav Explorer, drop me a line.
> >
> > Mark
> > Santa Cruz
> >
> > --- In electricboats@yahoogroups.com, jim_ranger_26 <no_reply@> wrote:
> > >
> > > Hi Mike, Welton, Arby, Keith, and Pastor Brett,
> > >
> > > Thanks very much for the quick and informative replies! I'm in the process of going through the info, which will take a bit to digest. It may already be addressed by someone, but, there are a couple of things that have occurred to me as I did some research while awaiting the replies from you.
> > >
> > > There doesn't seem to be much in the way of technical specs on components offered for sale - it's pretty much model number and price, the Motenergy/Mars web site being a prime example. One thing that any motor that is going to be used as a direct drive on the shaft may need to accommodate is axial stress along the length of the prop shaft. Does a direct-drive motor need to have a beefy axial thrust bearing, or is that not necessary as the through-hull bearing takes care of that? I suspect that, in ICE-conversion setups, there is a thrust bearing in the transmission that takes that load. If that's the case, it seems to me that people are going to quickly wear out the bearings in their expensive brushless motors (which I'm postulating are designed primarily to support side-loading, e.g., for motor weight and torque) if they don't have an axial thrust bearing in the through-hull fitting and aren't using the existing ICE transmission's thrust bearing. This is the kind of thing that a backyard mechanic would likely not be aware of, and is one of issues that the commercial setups address.
> > >
> > > I'd read that the power controllers typically used for boating e-drives were originally programmed for automotive/vehicular applications, as that's the market for which they were designed (e.g., golf carts, on up), and that the requirements for sailboat applications are far different. I am aware that Tesla, GM, Toyota, Nissan, etc., have spent major money on that problem alone, and I can readily see the sailboat profile consisting of long, full-power runs while motoring in/out of port, separated by potentially much longer regeneration periods while sailing, but, vehicular activity would be much more start/accelerate/decelerate/stop ... repeated at varying intervals (e.g., stop-and-go traffic) or smooth-acceleration/run-at-top-speed/smooth-deceleration (e.g., highway driving). I assume this is another area where the commercially-built boating systems manufacturers are doing the extra required programming work (and perhaps even controller hardware redesign) and, if they're not, then the system may not perform as efficiently as it should, and may even suffer early failure due to unplanned-for thermal/current stresses.
> > >
> > > I realize that battery technology is one of the most rapidly-moving targets (particularly power-to-weight), but, in (non-racing) boating applications, weight may not be as critical a factor as it is in vehicular applications (and, most recently, e-drives for aircraft - I'm a pilot and will eventually be interested in an e-aircraft, if/when the battery costs come waaaay down). Given that, are off-the-shelf (aka cheap) deep-cycle marine batteries just fine, and are there disadvantages to sealed-cell (aka maintenance-free) models, i.e., is it better to be able to add water to increase battery life? Having spent time on subs in the Navy, I'm very aware that non-sealed batteries can vent hydrogen gas, and I know that sulfuric acid vapors can build up in enclosed boat spaces, which can create an eye irritant if the vapors can make their way into below-decks living spaces (I'm guessing that, unlike the hydrogen, the sulfuric acid vapors are heavier than air).
> > >
> > > So, having thrown those bones out for chewing, I will now retire to my reading chair and peruse in detail the info via the links you so kindly provided! I would very much like to visit with those of you whom have made the offer, and will be in individual contact to set up times when we can get together. It probably won't be Sunday, June 12th, as I managed to pull a back muscle Saturday afternoon (no, not working on the boat, just lifting a box at an awkward angle at home - I should know better, I've done this every few years since I was a kid, as I have a longer back than is typical for my height, and need to not lift while reaching - Forrest Gump was right, stupid _is_ as stupid does! ):
> > >
> > > Thanks again, and All the Best,
> > > Jim
> > >
> > >
> > > --- In electricboats@yahoogroups.com, jim_ranger_26 <no_reply@> wrote:
> > > >
> > > > Hi everyone,
> > > >
> > > > Just joined the fray and wanted to get in contact with others whom have done conversions of sailboats (Ranger 29, in my case) with an existing dead Atomic 4 engine. I read the article in the June 2011 Good Old Boat where Joe Steinberger converted a Tripp/Lentsch 29 to an e-drive, and he provides a list of components and suppliers, but, he didn't go into any detail about how the components were chosen, what trade-offs he made, where he obtained details and specs for the components and how to hook them together, or how to evaluate other options.
> > > >
> > > > In looking briefly at the files and links section here, it appears that a bunch of marketing info has been dumped in mostly by suppliers/vendors, along with a plethora of links to a wide range of equipment and enthusiastic hyperbole, but, I haven't seen anything obviously labeled something like "Start Here". I'm an ocean engineer and computer scientist, so, I'm quite capable of understanding the technical details, and could design and install a system from scratch, given enough time with a McMaster-Carr catalog. However, I was hoping to come up with a variation of something someone else already has working for a sailboat similar in size to mine, and to replace an in-board engine.
> > > >
> > > > Since the Atomic 4 engine in my boat was DOA when I bought the boat, and its problems are too difficult to diagnose, much less repair, down in the bilge, I plan to pull it and do an overhaul in a much more comfortable location where I already have all of the needed tools, parts, etc. However, it's going to be a part-time effort (especially now that the weather is so nice), so, I wanted to just drop the components for an e-drive system in, connect it to the shaft, and be able to get in and out of the berth/channel into SF Bay from Marina Village in Oakland. I'll only need a minute, or so, of drive time to get between my slip and the channel, and occasionally, I may need up to 20 minutes of drive time if the wind is coming directly down the channel and I don't feel like tacking every 30 seconds.
> > > >
> > > > Steinberger gets up to four hours at three knots, and up to two hours at four knots, which would allow me to get anywhere in the SF Bay area when/where sailing would be difficult. Are there significantly different options from the components listed in Steinberger's article, or is that a reasonable-enough solution that I can just go with it? Here's what he used:
> > > >
> > > > Motenergy (nee Mars) Electric ME0201013601 brushless motor $450
> > > >
> > > > TeamDelta RCM187 Etek motor mount $ 60
> > > >
> > > > Kelly KBS48101 brushless motor controller $200
> > > >
> > > > Crydom solid-state relay $100
> > > >
> > > > ProStar PS-15M-48V solar charge controller $200
> > > >
> > > > Suntech 20-watt, 24-volt solar panels (2 each) $140
> > > >
> > > > Kelly HWZ Series 48-to-12-volt, 300-watt converter
> > > > (for ship's power) $130
> > > >
> > > > Kelly F4815 48-volt, 15-amp battery charger
> > > > (for charging from shorepower) $200
> > > >
> > > >
> > > > Thanks for any pointers, and hope to be able to find anyone with a similarly-sized converted sailboat so we can compare notes, and if you're on the West Coast, perhaps we can meet so you can show off what you've done.
> > > >
> > > > Thanks a boatload, and All the Best!
> > > > Jim
> > > >
> > >
> >
>
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