4800kv+40aEsc+5000mah11.1v li po?

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just a quick question to any one in the know. I have a 4800kv motor with a 40aEsc & a 5000mah 11.1v li po. will i cook my motor or Esc i have water cooling on both any info will be valued thankyou.

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karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Topic: 4800kv+40aEsc+5000mah11.1v li po? Posted: 07/Jun/2009 at 9:43pm
	just a quick question to any one in the know. I have a 4800kv motor with a 40aEsc & a 5000mah 11.1v li po. will i cook my motor or Esc i have water cooling on both any info will be valued thankyou.

W3FJW Ron Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Platinum (US) USERID: 63218 Forum Admin Joined: 19/Feb/2009 Location: Tacoma WA Online Status: Offline Posts: 9067	Quote Reply Posted: 08/Jun/2009 at 2:55am
	Need more motor specs to make a determination. Voltage rating, current draw, link to motor, etc. Sounds like it will be in a boat. Only thing that can be determined presently is that at 40A power input to motor would be 440 watts.
	*Best Regards* I can only remember half of what I say.... I used to walk on water 'til I found out it was more fun sitting in the boat drinking beer Ron

karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Posted: 08/Jun/2009 at 6:20pm
	Thankyou Ron for taking the time to msg me . The set up i explained is in a boat its the ARPRO 700EP offshore race boat it has a 1520kv water cooled motor & the 40a esc set up i explained. i am currently using a 3200mah 11.1v 3s1p. its quick but i want to go faster thats why i have bought a 4800kv motor & a 5000mah 11.1v li po the new motor conectors are exactly the same as my exsisting motor as is the new battery it has a deans conector with balance cord. i dont have vary many specs as i am new to this . i checked the site i bought hte 4800kv motor from and all they had is this... battery.2-3s/2200mah+ shaft diam.2.3mm diam 2.5.2mm L ect .And all i know about the esc is that its a brushless esc & its water cooled with a power logo on it im sorry i dont much more about the current draw or voltage rating. thankyou again for taking the time to reply sincerly karpy 78 cheers mate.

karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Posted: 08/Jun/2009 at 6:32pm
	Hi Ron i fogot to metion type in ARPRO rc boat in your search engine you may find the specs you were asking for and you will get a video of the boat in action cheers mate karpy78.

SeaComms Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 97362 HobbyKing aficionado Joined: 19/Feb/2009 Location: Noosa Australia Online Status: Offline Posts: 1226	Quote Reply Posted: 08/Jun/2009 at 8:25pm
	Hey karpy, the info on that boat is a little vague, but my guess would be that if the boat is supplied with a 40 amp ESC is probably drawing around 30 amps or so in stock setup. Upgrading to a 4800kv motor is going increase your no load prop speed by a factor of 3, in an ideal world with the same load you could easily expect your current draw to increase by the same factor or most likely a lot more. In other words, you will fry your ESC if you use the same prop, no questions asked. To get more speed, you will need to find a prop calculator for boats and throw the combinations in there. You will also have to increase the ESC in size, as any increase in speed comes at a cost, and the cost here is increased current. The exact figures I can not give you as I am not into boats, but a bit of a search did turn up this site, with a boat version of motorcalc (a program we use for aircraft to detirmine pitch speed, current draw, static thrust etc..) Have a look (I havent) it might help you out. http://www.rcboataholic.com/fe_calc.htm
	Cheers, Dave.

karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Posted: 09/Jun/2009 at 6:51pm
	thanks seacomms so what your saying is i need a bigger prop & a higher amp esc? could you or someone in the know recommend a compatible ESC thankyou for your time cheers.

karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Posted: 09/Jun/2009 at 7:22pm
	Thanks again dave just another quick question would a 125a ESC work well with that motor? or is that to big. & will that 5000mah li po run well with my current 1520kv motor & 40aESC? sorry mate i really am new to this. cheers 4 your help.

SeaComms Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 97362 HobbyKing aficionado Joined: 19/Feb/2009 Location: Noosa Australia Online Status: Offline Posts: 1226	Quote Reply Posted: 09/Jun/2009 at 8:21pm
	No worries karpy. If you increase the motor speed, the load will increase which will increase the current. The amount you are talking about increasing the motor speed will kill that ESC pretty much instantly. What I was geting at was you would need to reduce the prop pitch to lower the load. The following figures are an example based on rough gestimates - no actual calculations have taken place..... If you increase motor speed by a factor of 3, speed will increase by a factor of 3, amps will increase by (from experience with planes) by about 3 squared (factor of 9...). So, you would lower the diameter of the prop to reduce the load and static thrust (power off the standing start) and also reduce the pitch ( to reduce top speed) to get the current back to a useable figure. If you drop the pitch by 1/2, you would still end up with a 50% higher top speed, with not a great increase in current. I would have a good long play with that calculator I linked to, but you will need to know what the motor/prop statistics for you current setup and new motor are, then you can play with new prop sizes and see what sort of current it will draw. No point sticking a 125amp ESC in if the motor will only handle 60 amps. Putting a larger capacity battery on the current setup will not do much for speed - maybe a 10% increase at max due to the current battery not being able to handle the existing load properly - but it will give you a lot longer running time.
	Cheers, Dave.

karpy78 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 250228 Newbie Joined: 07/Jun/2009 Online Status: Offline Posts: 6	Quote Reply Posted: 10/Jun/2009 at 6:38pm
	thankyou thankyou cheers dave!!! that info has been very useful i experimented with a larger prop on my current setup it flew but i drained the battery pretty quick nearly had to go for a swim brrrrr i will put my regular size prop on & compare the speed & playtime..I really appreciate your time & effort. cheers mate,my 5000mah li po should come in the post this week i cant wait........I'll never grow up karpy78

SeaComms Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 97362 HobbyKing aficionado Joined: 19/Feb/2009 Location: Noosa Australia Online Status: Offline Posts: 1226	Quote Reply Posted: 10/Jun/2009 at 8:27pm
	Growing old is mandatory, growing up is optional
	Cheers, Dave.