Mystic C5000R scratch build - Page 10 - RC Groups
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Apr 17, 2012, 04:25 AM
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Quote:
Originally Posted by wparsons
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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Apr 17, 2012, 05:01 AM
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norbique's Avatar
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.
Apr 17, 2012, 10:29 PM
Registered User
wparsons's Avatar
Quote:
Originally Posted by OldMann
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.
Apr 18, 2012, 09:57 AM
United we race !
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
Apr 18, 2012, 09:59 AM
United we race !
Quote:
Originally Posted by renosa
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
Apr 18, 2012, 05:52 PM
Registered User
norbique's Avatar
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)
Apr 18, 2012, 10:51 PM
Registered User
wparsons's Avatar
Quote:
Originally Posted by pulsar
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).
Last edited by wparsons; Apr 19, 2012 at 05:53 PM.
Apr 19, 2012, 02:50 PM
Registered User
send me again plase.
Apr 19, 2012, 10:59 PM
Registered User
Quote:
Originally Posted by pulsar
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
May 03, 2012, 06:01 AM
Registered User
hi;
Send me Mystic C5000R autocad dxf data plaese.
Hakanisik26@hotmail.com
May 03, 2012, 06:04 AM
Registered User

Mystic C5000R 3d autocad data


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

send Mystic C5000R again plase


send again plase
May 03, 2012, 09:43 AM
United we race !
Hi.

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


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