Roland.
With a waterline length of 3.9m, your hull speed calculates to 4.6kts or 8.5km/hr Since your motor is rated to 60A @ 24V, that's 1440 watts or just about 2hp. Realistically with only 2hp, you will not get past hull speed. If the new motor can hit max RPM, then you can make the gear ratio "taller", closer to 1:1. If the motor hits max amp without max RPM, then you should go to a higher ratio, towards 2:1, by getting a smaller motor pulley or a larger driveshaft pully. Because of all of the additional variables involved, a calculated ratio will be merely a suggestion that would have to be proven by experimentation. It sounds like you're close, so I think that you can try different pulleys and you might be able to return the ones that you do not use.
Best regards,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, "babschaaf" <martine_roland@...> wrote:
>
> Hello electricboaters,
>
> I Own a litle electric boat, see attachment. http://www.electraboat.com/
>
> As you can see (click at more pictures) it has a 8.2: x 12 pitch prop.
>
> I replaced the electric motor with this one.
>
> http://www.astrosyn.com/shopimages/technicaldatasheets/Industrial%20Motors%20Technical%20Datasheet.pdf
>
> Type:A140 PLMW11 Bekr: PM Isol.KL: F
> U: 24V DC N: 1100min-1 Nr.: 2501
> I : 60 A IP: 42
> P: 1100 W ID: S2-30 VDE530/84
>
> I have on this motor a 100 mm diameter pulley with a belt to the propshaftaxle which has a 130 mm pulley. Now, I've experimented a bit with the best combination of pulley with this motor. Is there a way that you can calculate the best ratio for this?
>
> Of cource i realize that increasing the diameter of the prop would help, but obvious there's isn't enough room.
>
> I'm looking for a bit more speed as it seems that I even don't reach hull spead. Can this be done by altering the prop pitch=
> Can someone give me tips om how to get speed up? I have a potmeter to control the speed of the boat. I dont want to boat on full power all the time but if I need it, I'd like to have some more umph when needed. I live at a streaming river, not that fast, but enough.
>
> I'm not an electrician but trying to be as auto didactive as I can. Everyone I ask doesn't seem to understand really what I'm talking about. The only advice I get: bigger motor, or more batteries, but as I undertand that is not the thing or solution. So anyone of this good group with advice would be appreciated. I think you guys and girls should know and could lead me in the right direction.
>
> I also looked at the propellors from Torqeedo, but these seem to have a different way of attachment tot the prop axle.
>
> Thanks in advance,
>
> Roland Kruijer
> The Netherlands
>
No comments:
Post a Comment