what esc???

[fourq521]

hey guys.. I am putting a 36" cat together using duel leporad 4074 2200kv motors. plan on running 5 to 6s2p around 10000 MAH on each with 447 counter rotating props, what amperage esc should I run? was looking at the seaking 180 just to be on the safe side but I am thinking it might not be enough.. the motors are rated at 120 amps max but I don't know how to figure out what it will pull till its running..I am new to electric but have had many fast gas and nitro boats...??????

[Make-a-Wake]

I would use the T180's, but i would not use 447's on 5 or 6s. Go with x442 L and R on 5s which should be a good rpm zone. The T180's will do just fine with those props.

[fourq521]

well i bit the bullet and just ordered 2 of the castle creations hydra ice 240's.. don't think i will have any problems now.. but now I may rethink the motors..

[FighterCat57]

Whatever you decide, just make sure you have plenty of lipo amps available. The labeling can be misleading on some. If the voltage drop is too high it creates resistance on the ESC which may lead to premature failure. Although the ICE's have a nice protection circuit, there's still a chance the heat may build up too fast for the protection to catch it.

Also, if you over amp a motor, it creates more resistance for the ESC which can lead to failure as well.

Careful to match the system as not to over load any component.

Also, careful not to overload the hull with too much lipo weight. That can increase the prop load as well.

It's a fun balance to find and every hull has its own attitude.

Hope this helps, Enjoy.

[Fluid]

If you use those motors don't run 6S. That motor makes far too high an rpm for any use but SAW running on 6S. I run a 2200 Kv motor on 6S in my SAW cat, 42,000 rpm on the water and plenty of amps. A better rig for 6S would be 1500 Kv motors, still plenty fast with more torque and usable rpm.


.

[SLOW]

Whatever you decide, just make sure you have plenty of lipo amps available. The labeling can be misleading on some. If the voltage drop is too high it creates resistance on the ESC which may lead to premature failure. Although the ICE's have a nice protection circuit, there's still a chance the heat may build up too fast for the protection to catch it.

FighterCat57
In your opinion what would be enough battery for a setup like the one mentioned above?

I am looking at a setup similar to this. Would say a 5000mah 40c battery setup be enough?

[fourq521]

OK so please school me on motors.. what am I truly looking for in a motor besides longevity? I want it to be as fast as possible when I want it to be and turn it down so it's still drivable. was thinking mid to upper 60's maybe into the 70's. possibility of running it as a SAW as well at times. the hull is a crap EP but its been reinforced and beefed up a bit. I wanted to play with electric a bit before I stepped it up to a HPR plus I figured it would be fun to try to get one of these things to run well..

[fourq521]

Whatever you decide, just make sure you have plenty of lipo amps available. The labeling can be misleading on some.

Hope this helps, Enjoy.

yes that is something I am aware of. was thinking of running 45/90C lipos I also don't have to run 6S I didnt understand the whole volt / RPM deal till I read what Fluid wrote. what do you guys think of the neu-1515 1.5 Y motor for what i'd like to get??

[FighterCat57]

@ SLOW Just do the math and add some padding to it.

5000 mah 40c = 5 * 40 or 200 amps max constant.

Leave a 50% or so margin, so set the pack up to drain at 100 to 125 amps constant max.

You can have bursts above this for 10 seconds or so. This is why there's a burst rating on the lipos. So bursts of 200 amps would probably be OK both for the ESC and Battery packs.

With the high cost of lipos, I've found it best to use the 50% margin for sport setups. The HK lipos can and will puff if you overdraw them or of they are not rated correct.

So when you FE Calc your system, set it up to draw about 100 to 120 amps and work from there. =)

That's just my method, there's many guys on here that have their methods as well. I like to play it safe any more. I have a nice g-note worth of charred electronics in a box that have inspired this method. The box hasn't grown much lately.