Saturday, October 17, 2009

RE: [Electric Boats] Re: Small leg question

 

My conversion (www.evalbum.com/492) retains the mechanical reversing. To do
reversing on many controllers requires adding contactors, cabling and added
control. With the mechanical reversing mechanism already in place, I
couldn't justify it.

My outboard configuration:

· $450: ETEK 8HP brushmotor (since 2003? And running with same first
set of brushes)

· $250: Alltrax 48v controller housed inside

· $10: Papst 48v muffin fan attached to aluminum conical shroud,
aluminum taped to ETEK motor

· $20: 36v main contactor

· $100: Shaft coupler, custom made, spline to 7/8" keyway --- made
from old pinion gear, ground to 7/8" and bonded half-way into 7/8" keyway
coupler

· ½" thick motor mount plate, aluminum

· ¼" thick base plate, aluminum, mounts to lower unit after removing
powerhead

· ¾" thick aluminum standoff plates, q:3, locate motor above lower
unit base plate such that neither shafts don't need cutting

· Bolts to attach the above

· "False top" in cowling to blow motor exhaust air up into before
leaving cowl

· 36v system: Max 6HP electrical power to motor (36v, 130a)

Jon-

A wise man has several times said regarding EV's: "You can have low cost,
range, power --- pick any two."

You'd best heed this advise.

So you want cheap and you want 2-2.5HP of power. So you probably aren't
going to have much range as an option, especially given a dinghy and the
desire to avoid weight or what you would consider high cost lithium.

Your problem statement is too incomplete for us to help here.

We don't know: (1) volume available in your motor cowl, (2) whether or not
you are constraining yourself to a solution that fits in that cowl, (3) what
voltage range you consider, (4) what your cost target is.

It's kind of a non-starter.

But generally, you'll need the list I noted above---pick the motor you
want---but beware…unless you get a high efficiency motor, a 2.5HP motor may
be quite large. Even a high efficiency Leeson 12/24v DC motor (look at
Ebay) for nom. $120 will only get you 1-1.5HP and still be too high for your
cowling. You could by an Arby motor. You could convert an alternator to a
3-phase motor. We can't help you here since you really need to find your
cheap solution. For cheap control, you could make a simple 2- or 3-speed
drum controller and go old-school, saving controller money. Batteries: Get
used ones at local battery shop---$20-40 each for a deep cycle.

-Myles Twete, across the river in Portlandistan

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com]
On Behalf Of Colin Girvan
Sent: Saturday, October 17, 2009 8:57 AM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Re: Small leg question

I have a quick question for those of you who have done an outboard
conversion. Were you able to use the reversing electric motor for reverse or
do you have to use the mechanical reverse via the gearbox?

Colin Girvan

BC Canada

--- On Fri, 10/16/09, tmarks11 <no_reply@yahoogroups.com
<mailto:no_reply%40yahoogroups.com> > wrote:

From: tmarks11 <no_reply@yahoogroups.com <mailto:no_reply%40yahoogroups.com>
>
Subject: [Electric Boats] Re: Small leg question
To: electricboats@yahoogroups.com <mailto:electricboats%40yahoogroups.com>
Received: Friday, October 16, 2009, 10:16 PM

I would recommend either an Etek (brushed) or Mars (brushless version of the
Etek). Both are PMDC motors, with relatively high power to weight ratios.
Since they are PMDC, they are more efficient then their (larger, heavier)
cousins like an Advanced DC motor with field windings.

Both motors are manufactured by Mars Electric, who bought the design from
Briggs & Stratten when they ceased production of the Etek.

http://www.marselec tricllc.com/ me07081.html

The how? The simplest way is how Jim did it here:

http://www.psnw. com/~jmrudholm/ etekoutboard. html

Two aluminum plates gave offset above the top of the outboard lower unit,
providing room for a spider coupling ("Love-Joy coupling") to mate the
spline on the outboard to the shaft of the motor.

The brushed DC could use a variety of inexpensive golf-cart style
controllers. The brushless is more expensive, since it requires a special
controller that can take DC and produce a smooth multi-phase AC output to
the motor. Mars sells a version for $350. You can buy a SEVCON PMAC
brushless controller for $450.

--- In electricboats@ yahoogroups. com, "Jon n Wanda" <windyjon@.. .> wrote:

>

> Still looking for some ideas on electric motor system.

>

> Jon

>

> --- In electricboats@ yahoogroups. com, "Jon n Wanda" <windyjon@> wrote:

> >

> > I have a 4.5 HP Merc. what would be a good electric moter to replace the
power head with. The how is easy the what is the question.

> >

> > Jon

> >

>

__________________________________________________________
Ask a question on any topic and get answers from real people. Go to Yahoo!
Answers and share what you know at http://ca.answers.yahoo.com

[Non-text portions of this message have been removed]

[Non-text portions of this message have been removed]

__._,_.___
Recent Activity
Visit Your Group
Yahoo! News

Get it all here

Breaking news to

entertainment news

Share Photos

Put your favorite

photos and

more online.

Yahoo! Groups

Auto Enthusiast Zone

Passionate about cars?

Check out the Auto Enthusiast Zone.

.

__,_._,___

No comments:

Post a Comment