ESC help. Time sensitive

[s15driftking]

Hi guys,

I have a question about water cooled ESC's. I just bought a 41 inch genesis running a 2200kv motor but I need to buy an ESC. I am a bit confused about battery volts versus ESC amps. How is it that the turnigy 120a, 160a, and 180a esc all claim to be capable of handling 6S lipo?

As an RC car guy I have always thought (or seen a correlation) between "the higher the amp ESC the higher cell lipo it can handle... But these marine ESC seem to have such a larger rang of amperage and all handle 6s (120, 160, 180)


The whole reason I ask.... I am running dual 5s 40c 4000mah packs and need to find an esc I can order and receive by 3/1/13 to get it ready for the next day... The 160 and 180a are not in stock in hobbyking's USA wharehouse... So that won't work

Help!!! Anyone have a 160 or 180a for sale?

[viper1]

The Turnigy Marine 35A,60A,80A-HV,120A and 180A are all re-branded HobbyWing Seaking ESC's , same animal, different fur.
Might be easier for you to find stock

Here for example...

[s15driftking]

Yes, I assumed they were. Does anywhere else aside from hobbypartz carry hobbywing? Also, can you comment on the other question of why the 120, 160, and 180 all say they handle 6S? How is it possible that a 120 can handle 6s. Keep in mind I'm running 5s

[lenny]

What are your planes for the boat, Racing or sport running ?
6S is the max volts and with low amp setup on 6s but a high amp setup 5s tops on them.
You could use the 130a high volt esc with burst current of 180a instead and that will do 5s to 12s setups.

Hear you go,http://www.hobbypartz.com/hoforrcbo.html
http://www.offshoreelectrics.com/pro...-seaking-130HV

[lenny]

What 2200kv motor do you have ?

[s15driftking]

Leopard 3674 2200kv

[oscarel]

They're available here http://www.offshoreelectrics.com/pro...Speed+Controls
Steven ships priority so you might be able to get it in time.

[Fluid]

Leopard 3674 2200kv

I know you are not asking this, but I am afraid that this motor will not work well on your 41" cat. It is way too small, and on 5S will need to spin a very small, inefficient prop. You should consider exchanging it for at the least a 40x92mm motor with a Kv closer to 1400. Performance with your 3674/2200 motor will be very disappointing.


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[s15driftking]

What 2200kv motor do you have ?

This is a legitimate not-to-sound snobby question.

Why do you ask?

I say that because I want to learn.

[s15driftking]

I know you are not asking this, but I am afraid that this motor will not work well on your 41" cat. It is way too small, and on 5S will need to spin a very small, inefficient prop. You should consider exchanging it for at the least a 40x92mm motor with a Kv closer to 1400. Performance with your 3674/2200 motor will be very disappointing.


.

the guy who had it before me claims he went 58mph with this boat (x640 prop) on 5S batts. thats good enough for me.

Could i go faster with lower KV?

[Fluid]

This is a legitimate not-to-sound snobby question...Why do you ask?....I say that because I want to learn.

To whom are you replying/asking?




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[Fluid]

the guy who had it before me claims he went 58mph with this boat (x640 prop) on 5S batts. thats good enough for me.

I thought you wanted to learn? Okay, good luck. You were warned.




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[s15driftking]

I thought you wanted to learn? Okay, good luck. You were warned.




.

I think you read it wrong or i said it wrong. I was saying that I would be okay if it topped at 58mph. I absolutely want to learn.


I jsut wanted to compare notes.
the other ocmment was directed to lenny, he is quoted in my reply.

[s15driftking]

I also want to address my original question:

I am a bit confused about battery volts versus ESC amps. How is it that the turnigy 120a, 160a, and 180a esc all claim to be capable of handling 6S lipo?

As an RC car guy I have always thought (or seen a correlation) between "the higher the amp ESC the higher cell lipo it can handle... But these marine ESC seem to have such a larger rang of amperage and all handle 6s (120, 160, 180)

[HTVboats]

The power requirements for a boat vary with size and weight. Bigger means more watts with a range that is probably greater for boats From 300watts on a small boat to over 5000watts in large hulls. ESC's are more often made for the popular battery sizes which in boats seems to be 2-6s with 4 and 6s popular for mid size hulls 25-40 inches. Watts = voltage X amps. Or divide the wattage of a motor by the voltage and you get the amps required for WOT. I have a 31" tunnel and use 2 different motors, one on 4s and the other on 6s. I run a 1515 Neu 2200 kv on 4s and a 1515 Neu 1500kv on 6s. the props and speed are similar with the 6s a tad faster. Both 2500watt motors and the 6s batteries are larger with the same mah rating. (more potential run time) The 2200 X 14.8v gives a no load of 32500 rpm and the 1500 X 22.2v has a no load of 33300 rpm. The potential amp draw for the 4s is 2500w divided by 14.8 giving a load of about 170 amps. The 6s setup -2500 divided by 22.2v = 112 amps for full power. A 180a esc will be fine on 6s but marginal on a 4s motor with the same watts (HP). As you go up in cells the voltage does the work. Why you see 200-240amp ESC's for large 5000 + watt motors with low KV's and higher voltages. KV's are basically similar to gear ratios coupled to different prop piches and diameters. Matching the hull size and weight to the appropriate motor size (watts) with consideration to battery size and voltage is how things work.
Your 41" hull needs a larger than 36X74 motor. The 2200 kv is also working against you. I run a 39" DF mono on 6s with a 1600kv 1520 Castle (40x82)with a 200amp Swordfish. A t-180 would work fine also. thats a 3500 watt max(rated) motor drawing 160 amps with not too stiff props and capable of low 50"s. I have seen some speed claims of up to 100mph RC boats many times on the forums and ebay. Your 58mph guy is blowing smoke.
Mic