Re: [Electric Boats] Re: Catalina 27

Yes, I have learned that.  I'm leaning towards the MARS (Montgomery.com).

 

Their model 0708 is 4.8 Kw (6.4 HP), the 0709 is 6 Kw for about 8 HP, the 1004 is I believe 8 Kw for about 10 HP & the 1003 is 11.4 Kw for over 15 HP!

 

I think that for my little Columbia 29 in Lake Winnebago i can get by with the 0708 @ 6.4 HP & 3360 RPM max @ 48 V.

 

With a 2:1 reduction & an Alltrax 4834.  I've heard too many good reports on this setup, and it's best for me to learn from the experience of others.
----- Original Message -----
From: "Myles Twete" <matwete@comcast.net>
To: electricboats@yahoogroups.com
Sent: Friday, March 18, 2011 1:17:06 PM
Subject: RE: [Electric Boats] Re: Catalina 27

 

Regarding that MANTA motor:  I would advise being very careful.  Read everything you can about this before putting your money into it.  From what I've been able to gather from a brief search online is that these "MANTA" motors are remanufactured Briggs & Stratton ETEK motors and assembled by Thermodyne Systems of California: http://www.hydrogenappliances.com/manta.html .  I wouldn't go so far as to give them the credit of being called a manufacturer.

If you do buy one of these motors, be sure to note whether they sent you one of their "unbalanced" "Manta-V" motors instead---noted by a "spot of green paint on the rear casing and rotor": http://www.hydrogenappliances.com/manta_VIB.html

 

I advise extreme caution with this company.

Their claims and perhaps all of their specifications need to be taken with huge grains of salt.

Several years ago a close friend purchased one of their SC12 permanent magnet alternators (PMA) to generate power from a small steam engine on his steamboat.  The claims on their website for these motors indicate "lots of low end power", "great for heavy amp loads", "low cogging", "the higher the amp, the harder they work" and "warranty – 90 days parts and labor".

Their lame motor curve just adds to confusion and begs questions that they would not answer prior to our purchasing a PMA:

 

Well, we hooked this PMA up to the steam engine and indeed it did generate power to charge the batteries.  However, it also generated a loud whining sound (due to its cogging!), but worse, the most we could get it to deliver to the 12v battery bank was about 20amps.  But the real showstopper was that the PMA got VERY HOT !  There's no way we could use it.  Far from this being a motor/generator that is "great for heavy amp loads", this alternator was worse than the standard alternators we had tried.  We immediately contacted Thermodyne and spoke with their owner.  He rudely told me that there's nothing wrong with their PMA's or their claims or specs and that since we had powered the PMA, we could not send it back to get our money back.  My friend was out $300 for this mistake!!!  Want to buy a lightly used PMA SC12?  I know where you can get a good deal on one!

 

Anyway, I personally wouldn't give these people a dime of my money.  That they still put out claims on their web pages that do not make sense and mislead, for serious applications like driving a car or a boat, you should deal only with companies that demonstrate they understand the technology and don't rely on false or misleading claims.  I would not believe their claims for their 48v, 10HP remanufactured ETEK motors and would not trust that they would be balanced or last for any length of time.

 

Caveat emptor-

 

-Myles Twete, Portland, Or.

 

 

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of shea1719@comcast.net
Sent: Friday, March 18, 2011 7:23 AM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Re: Catalina 27

 

I was looking at that MANTA (similar to the MARS) 10HP MAX, 3450 RPM @ 48V (draws 155 AMP @ 48V) 7.46 Kw, Torque 1.14 in lb / AMP

 

Brush type (lithium graphite brushes), ETEK face mount, 7/8 shaft diameter.

 

Of course I would never, or hardly ever run it up at that range, but it's rated for that 10HP continuous, 94% efficiency; it's nice to know I have that power on tap if I need it.

 

What are my controller options for this kind of a set-up??

 

Also, $300 seems like a small price to pay to get rid of that tap switch and all of the associated problems it would create...

 

Thanks!!
----- Original Message -----
From: "luv2bsailin" <luv2bsailin@yahoo.com>
To: electricboats@yahoogroups.com
Sent: Thursday, March 17, 2011 9:44:46 PM
Subject: [Electric Boats] Re: Catalina 27

 

Hi Michael,
They are about 300 bucks as Matthew mentioned. There are a few different versions so you'll want to make sure you get the right one for whatever motor you pick. There are a few companies that sell electric vehicle kits, "hot rod" kits for golf carts and the like. Can't think of any names right now. I'm on the road this weekend so I may or may not have internet access, but if could send me an email reminder I will dig up some wiring diagrams. The Alltrax site is good too, but they have a lot if different versions so it takes a little digging.
Yes, that was the original setup on my Catalina 27. The same controller was on my Albin 25 last summer, but with a Mars PM brush motor. It worked great but ran a little hot so I had to install a fan. Pics of that one are under "Albin 25" in the photo section.
The Alltrax is a very simple but rugged Pulse Width Modulation controller. PWM basically means that it switches the current to the motor on and off at a steady rate, something like 20,000 times per second. While the rate stays steady, the pulse width (on time vs off time) is varied in response to your throttle setting. The motor tends to smooth out those on-off pulses due to it's inductance, which can be thought of as a form of electrical inertia. Bottom line, you're effectively varying the DC voltage that the motor sees. The reversing relay simply swaps the motor leads.
Sorry I got a little long winded there, hope it makes sense.
Jim

--- In electricboats@yahoogroups.com, "ComcastMail" <shea1719@...> wrote:
>
> Jim -
>
> Your previous application of the Alltrax AXE controller with a reversing relay perhaps answers my previous question. Was that Catalina with the Briggs Etec a brush type motor?
>
> How much does that controller cost, and basically how do the work? Can you attach a PDF wiring diagram for this kind of system?
>
> Thanks again
>
> Michael Shea
> ----- Original Message -----
> From: luv2bsailin
> To: electricboats@yahoogroups.com
> Sent: Wednesday, March 16, 2011 1:46 AM
> Subject: [Electric Boats] Re: Catalina 27
>
>
>
> Hi Guys,
> I dug through my archives and found some old pics of my first electric installation. You can see them under "Jim McMillan..." in the photo section. It was done at Ventura Harbor (CA) back in 2004. I just sort of threw it together as a proof of concept so it ain't pretty. It did about 2kt at 900W, 3kt at 1500W, 4kt at 2800W, and 5kt at 5400W with the cheesy little fouled 9-inch prop as seen in the pics. I think the reduction was around 2.5:1 at the time.
> The chain drive worked great for playing with ratios, but was horribly noisy. The motor was a Briggs E-Tek and controller was an Alltrax AXE with a reversing relay. I still laugh when I see the throttle control, I threw it together in about a half with some Radio Shack parts, scrap paneling, drywall screws and hot-glue. Anyhow, it was a lot of fun and I learned a lot.
> Cheers,
> Jim
>
> --- In electricboats@yahoogroups.com, "sloop_wasnt_me" <sloop_wasnt_me@> wrote:
> >
> >
> >
> > --- In electricboats@yahoogroups.com, "Tom" <boat_works@> wrote:
> > >
> > > Hi,
> > > Are you certain you can run the MARS 3001 at 72V? I thought it was spec'd at 48V nominal.
> > >
> > > I ask because the output of my Elcon charger is fixed at about 3V higher than I like to charge, and adding another cell to my battery bank would get me a bit more KWH and get the charge profile more in line with my needs.
> > >
> > > -Tom
> > >
> >
> > I'm not positive but I think it will run okay at 72v, Tom. At least Kelly Controls thinks it will cause they sell a kit, with 48v (KBL48301) controller, but offer upgrade to the 72V controller and they throw in a 15A charger too. Obviously they mean for the motor to be run at 72V or they would not upgrade the charger. I will check for sure before placing an order. If it don't work out then I guess I still got my Atomic 4 to git 'er done.
> >
>