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Old Apr 17, 2012, 04:25 AM
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Quote:
Originally Posted by wparsons View Post
Practical output wattage = V * I * E, you don't need to know anything about resistance, etc.

V = voltage
I = current
E = efficiency.

Input wattage is simply V * I.
I do not think this formula is correct.
This formula would result E ; E= P /V*I
This means that if I lower the supply, increase efficiency .... that contradicts the laws of physics.
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Old Apr 17, 2012, 05:01 AM
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United States, HI, Honolulu
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I am by no means an expert, but I think since efficiency is always less than 1 (that is 100%), the above formula should be consedered OK.

input wattage Pin=Uin * Iin
output wattage Pout=Uin * Iin * efficiency (which is <1)
so P out is always less than P in.
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Old Apr 17, 2012, 10:29 PM
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Canada, ON, Whitby
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Quote:
Originally Posted by OldMann View Post
I do not think this formula is correct.
This formula would result E ; E= P /V*I
This means that if I lower the supply, increase efficiency .... that contradicts the laws of physics.
Input Wattage = Voltage * Current.

Output Wattage = Voltage * Current * Efficiency or Output Wattage = Input Wattage * Efficiency

Rearranging that gives:

Efficiency = Output Wattage / (Voltage * Current) or Efficiency = Output Wattage / Input Wattage which is 100% correct.

Not sure what you mean about lowering supply and increase efficiency or contradicting the laws of physics, all the above is definitely correct as far as physics is concerned.
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Old Apr 18, 2012, 09:57 AM
United we race !
Slovenija, Ljubljana
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Iīm still confused, about this discussion on efficiency.
Max 75A on 11S is correct data (3025W).

Lowering the voltage increases current, so I think on 6S (120-160Amp)?

I think itīs like that isnīt it?

Thanx to all comments.

Kruno
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Old Apr 18, 2012, 09:59 AM
United we race !
Slovenija, Ljubljana
Joined Oct 2006
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Quote:
Originally Posted by renosa View Post
Pulsar how you ar going to cool this motors?
they are not water cooled!
For coolin, I wil made something like this:

http://www.hobbyking.com/hobbyking/s...ount_30mm.html

or using this:
http://www.hobbyking.com/hobbyking/s...75MM_BOAT.html
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Old Apr 18, 2012, 05:52 PM
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United States, HI, Honolulu
Joined Dec 2002
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I use the T600 turnigy motors, 1400KV on 6S and I use the cooling plates in your 2nd link. They work good!
The ourtunners are torque monsters!!!

Here is the first test run of the boat:
Lithium (1 min 32 sec)
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Old Apr 18, 2012, 10:51 PM
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Canada, ON, Whitby
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Quote:
Originally Posted by pulsar View Post
Iīm still confused, about this discussion on efficiency.
Max 75A on 11S is correct data (3025W).

Lowering the voltage increases current, so I think on 6S (120-160Amp)?

I think itīs like that isnīt it?

Thanx to all comments.

Kruno
If you lower the voltage without changing anything else, current draw will actually go down (opposite goes if you increase voltage but change nothing else). If you want to keep the same wattage output you would have to prop up to increase load (and amp draw).
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Last edited by wparsons; Apr 19, 2012 at 05:53 PM.
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Old Apr 19, 2012, 02:50 PM
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send me again plase.
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Old Apr 19, 2012, 10:59 PM
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United States, VA
Joined Aug 2011
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Quote:
Originally Posted by pulsar View Post
And this I hope you all know what it is.

I have obut 20 models that I draw myself.
If someone need something, contact me I see what I can do.
pulsar, your work is very impressive and your generousity is unparalleled. Myself and many others might be interested in this model below. Do you happen to have a design of the Outerlimits SV43?

Specs: http://www.outerlimitspowerboats.com/43SV.htm
FE model: http://www.e-powerboat.de/archives/515
Profile pics: http://i62.photobucket.com/albums/h9...hipmodlow4.jpg
Very good scratch built: http://www.offshore-rc.com/forum/ind...howtopic=25587
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Old May 03, 2012, 06:01 AM
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hi;
Send me Mystic C5000R autocad dxf data plaese.
Hakanisik26@hotmail.com
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Old May 03, 2012, 06:04 AM
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Mystic C5000R 3d autocad data

hello
my name is hakan
send me Mystic C5000R 3D autocad data, plaese
hakanisik26@hotmail.com
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Old May 03, 2012, 06:21 AM
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send Mystic C5000R again plase

send again plase
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Old May 03, 2012, 09:43 AM
United we race !
Slovenija, Ljubljana
Joined Oct 2006
117 Posts
Hi.

Ok here is the 3D file of mystic c5000r V2.
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Old May 04, 2012, 02:13 AM
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tanks a lot of
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Old May 04, 2012, 04:28 PM
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Hi, check your pms. I need plans for the hrp mono. Please reply!
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