Hi Mr. Dej,
In my case, I am waiting for hard numbers. Performance statistics of
this motor installed in a boat. Testimonials are great but are best
saved for late night television infomercials. Frankly, if this motor
performs according to the claims, then I will be right there with cash
in hand to convert my boat. But until I see actual in-the-field
measured data, as well as bench-test data, then I am going to hold on to
my money. It all comes down to that. People can make whatever claims
they want, and others can pick apart those claims all they want. The
only thing that stands on its own is data. And then only if it is
produced by an independent 3rd party without a vested interest in
selling the motors.
For the time being, there seems to be some friction over how a 2kW motor
can push a 4 ton boat into 30kt headwinds and 4' chop, against a 2kt
tidal current. People with better brains than mine seem to be claiming
that doing so takes more energy than the 2kW motor can deliver to the
water. But all of this is conjecture since Arby has not provided any
performance curves for his motor. The ball is clearly in his court on
this matter. Numbers that interest me are:
- amps vs. speed graphs for boats of varying mass, specifying prop size
for each boat.
- as above in different conditions of wind, wave and current.
- Provide Google Earth tracks (.kmz files) from various runs in SF Bay
(or any other suitable proving ground with known and verifiable
conditions), indicating battery amp draw and prop shaft RPM at each data
point. Truly interested parties could independently verify the bay
conditions (wind, waves, current) using the timestamps in the KML file.
Real-world and lab data will help me in forming my purchase decision.
And the lack of real-world or lab data is in itself data that I will use
in making my decision. I am sure that I am not alone. The (potential)
customer must demand this information from any vendor. If the vendor
_can't_ provide it, then they are no different than a garage tinkerer,
assembling bits of electronics. If the vendor _won't _ provide it, one
can only wonder how the after-sales support experience will be.
Personally, I like the idea of a direct drive motor in a sealed unit
that can take several minutes of immersion. I like this motor. I want
it to work as claimed. But I barely have the money to do an electric
conversion once, let alone twice in case I make a poor choice. So I am
going to "wait and see" how this plays out.
Cheers,
/Jason
--- In electricboats@
>
> Good Day to you "mtrgy" all in the group who have been involved in the
bashing or dis belief of the aforementioned Advanced Marine 2K 24v $2500
direct drive motor.
>
> My name is David Johnson. Some know me as the guy doing the
documentary on the conversion of my 1979 30' Hunter 9,700 lb snailboat
from Yanmar YSM12 diesel to full electric.
> 4 months in the study of all of the available manufacturers of
electric re-power options and I was most intrigued by the EV community
myth that is the Arby Bernt designed motor.
>
> The maiden voyage was made by a 35 yr vet of the Florida Coast Guard.
After 2 days of using the motor in every way one can imagine his final
words were "How can I get one of these for my boat?"
>
> Even he was convinced by the power and efficiency of the motor based
on delivery of needed "on demand" motion and simply keeping us out of
danger (to include 30 mph head wind gusts, 5-7 ft swells, against an
incoming St Johns current in a 50 yrd wide channel) as we zig zaged
between a parade of ocean freight liners. Not such a good move, I know.
Actually video coming soon.
>
> 2 months now and practically every week, sometimes a couples days
given the time, we are out on the water with the flick of a switch. The
ICW is very much like the SF Bay, conditions changing in the blink of an
eye, not ever to our benefit. As some of you have seen on my "blatant
commercial plug" website SILENTRUNNINGSYSTEM
is a completely solid piece of marine compliant gear.
> An attractive little box to boot.
>
> So without website marketing or online visual in-stock reassurance I
am here to tell you, it is alive and it is kicking...and available.
>
> With all the advice and expertise Arby has shared on this group, and
to many of you personally, there should be nothing but a resounding
"Well alright! It's about time" or simple "Good for you Arby". While so
many on here are spending weeks trying to get a treadmill motor to work
under water, Arby has been taking all of the questions and postings and
data into his garage and producing another option for you, yes YOU.
>
> You, the readers and group members are the ones that asked for this
type of safe, affordable, and efficient motor. Arby had the know how to
make it. How long ago did Shelley write the story of Dr Frankenstein?
Jeeesh!
>
> Now go switch your boat on and enjoy the summer.
> DEJ
>
>
>
>
>
> --- In electricboats@
> >
> > What is really unfortunate is that such a blatant commercial plug
and one so full of BS is posted here.
> >
> > There is no way a 2KW motor is going to provide good results in
boats up to 32'. It is even less possible that it will provide good
performance with the varied array of boats and propellers quoted. Will
it move these boats? of course. Will it meet the expectations of most
sailors? Not likely.
> >
> > These kinds of posts do nothing to advance the cause of electric
propulsion and should be ignored and removed from this site.
> >
> > Scott.
> >
> > --- In electricboats@
<aweekdaysailor@
> > >
> > > To be fair, both of Arby's prior references were future tense - so
yeah he was late, but that hardly constitutes deception. He's
contributed meaningfully to the group, has an apparent wealth of
knowledge and has a product that will likely prove useful to at least
some members of the list.
> > >
> > > That TS hasn't updated their site is also not surprising. They are
probably busy with yet-another motorcycle that can tear it's own tires
off.
> > >
> > > But...healthy skepticism is warranted, and I would be extremely
interested in some actual speed/watt and efficiency graphs. One
marketing challenge is that the alleged increase in efficiency will only
be obvious in actual installations - it's unlikely the motor itself will
show more than a few percentage either way. It's the removal of
drivetrain loss factors (belts, chains, bearings) that should make the
most difference.
> > >
> > > -Keith
> > >
> > > --- In electricboats@
wrote:
> > > >
> > > > Arby, respectfully, you have been claiming literally for months
now that
> > > > your new drive assembly was "available at Thunderstruck-
Again you
> > > > claim this, and again, while there are a half dozen different
makes of
> > > > motors listed on that site, there's not a single web page I can
find at
> > > > Thuderstruck substantiating they stock your motor/controller.
There are no
> > > > text references, let alone photos, motor specs or motor curves
for your
> > > > motor/controller. Now maybe they are available or maybe
not---but to have
> > > > folks "call Mark" sounds more like you're asking us to build
demand for
> > > > Thunderstruck to buy these from you, stock them and post them as
> > > > available---
haven't seen
> > > > publicly available performance specs for your motor/controller,
I'm
> > > > skeptical---
post to this
> > > > list that your hardware is available from a substantially
website-based
> > > > company that hasn't even mentioned your hardware on their
website.
> > > >
> > > >
> > > >
> > > > Moderator NOTE to ALL: This is not a sounding board or focus
group for
> > > > marketers, developers, thesis writers, etc. Attempts to use this
list in
> > > > this manner leads to your list postings being moderated
(including being
> > > > delayed, edited or deleted).
> > > >
> > > >
> > > >
> > > > -Myles Twete, List Moderator, Portland, Or.
> > > >
> > > > From: electricboats@
[mailto:electricboats@
> > > > On Behalf Of arbybernt
> > > > Sent: Friday, July 10, 2009 12:34 AM
> > > > To: electricboats@
> > > > Subject: [Electric Boats] Direct drive brushless DC motors now
available
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > Now available at Thunderstruck-
Propulsion
> > > > 24v, 2kW, direct drive brushless DC motor specifically designed
to replace
> > > > inboard ICEs in sailboats up to 32 feet. With an internal
controller, the
> > > > motor unit is sealed to 10' of temporary submersion, yet vented
to dry air
> > > > to maintain atmospheric pressure within the motor housing,
relieving seal
> > > > pressure and eliminating grease migration. The 1" keyed
stainless steel
> > > > shaft extends eight inches from the motor rear face to
accommodate hull
> > > > curvature. The shaft exits five inches up from the bottom of the
motor
> > > > housing, and in the center of the 9.375" width. The motor
housing is 13.75"
> > > > tall, 3.25" thick, and weighs 30 lbs. Mounting is achieved via
four 1/2 x
> > > > 13tpi tapped heli-coiled blind holes, arranged symmetrically
about the drive
> > > > shaft on the sides of the housing. Simple mountings can be
fabricated from
> > > > 2"x2" aluminum angle, or with 1/4" aluminum plates secured to
both the motor
> > > > and engine stringers. Wiring does not require a relay or any
external
> > > > battery switch. Battery leads are designed to be connected
directly to the
> > > > main battery. A second string can be combined with the primary
string using
> > > > a two position switch. Logic power is controlled by a remote
switch, and
> > > > consumes a mere 40mA on standby (50mA with an LED power
indicator). When the
> > > > logic power is off, there is no measurable battery drain. There
are no
> > > > exposed terminals, no additional connectors, and no external
wires between
> > > > the motor and the controller. With a no-load speed of 1000rpm,
the motor
> > > > achieves peak output at 875rpm, making the use of large
efficient propellers
> > > > possible. Although an aggressive prop will provide peak
performance, the
> > > > motor torque range is broad and efficient, making nearly any
prop functional
> > > > without modifying the boat. I'm currently fitting a Ericson 27
(6800lb
> > > > displacement) with an Advanced Marine motor and an 11x11 3bl
prop, having
> > > > met success with both a 30' Hunter (9700lbs, 12x7 2bl prop) in
St.
> > > > Augustine, Fl, and a 30' custom sailboat (~8000lb, 12x8? 2bl
prop) in
> > > > Marshall, Ca. Both boats have been providing reliable service,
and cruise
> > > > comfortably on 24v at 40 to 60 amps. I hope to splash the
Ericson this
> > > > weekend, and will be conducting testing next week, pending an
unpredictable
> > > > travel schedule, in the challenging conditions of San Francisco
Bay. I'll
> > > > post pictures and stats when the installation is complete.
Energy will be
> > > > provided by two sets of 2x12v, North Star NSB100FT 100aH AGMs,
located
> > > > within the existing motor compartment. Cooling is provided by a
shaft
> > > > mounted fan, directing air across the rear of the motor housing.
Motor
> > > > control is achieved with two encapsulated switches (logic power
and prop
> > > > direction) and a mil-spec wash-down grade potentiometer for
throttle level,
> > > > all provided. An optional ParSun throttle interface can be
pre-wired to the
> > > > motor. Control wiring is plug-and-play with the ParSun, or with
just three
> > > > 1/2" mounting holes for the included switches and potentiometer.
The
> > > > switches and pot can be mounted in any exposed area, but I would
recommend
> > > > keeping the ParSun covered when not in use to slow aging of
exposed rubber
> > > > cables.
> > > >
> > > > I invite your questions and comments. This design is constructed
provide
> > > > many, many years of reliable service, with the fastest wearing
part, a
> > > > double row sealed bearing (3305) resolving the prop shaft
thrust,
> > > > replaceable without disturbing the installed motor. The standard
warranty is
> > > > five years, full replacement, excluding over-voltage (<30vdc),
reverse
> > > > polarity, and shipping. Rebuilding damaged motors can be
accomplished by
> > > > returning the motor in the original shipping container. I am
offering an
> > > > unlimited lifetime warranty with the a-fore mentioned conditions
on the
> > > > first ten units, five of which are now ready to ship from
Thunderstruck-
> > > > Contact Mark in Sales during business hours.
> > > >
> > > > Be Well,
> > > > Arby
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > >
> >
>
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