Minicat Velocity Cat-New

[Rich]

It's not the Velocity 30A's that were blowing, it was the Tenshock esc's in the Micro Hydro and Starship. Somehow this got into the wrong thread. You guys can argue all you want. The fact is, and I sell the stuff, that anything over 25C used to blow the 30's!~ OK? I don't care why, I just know it did. Now with the new 40A's in the Micro Hydro, STarship and Mini ECO, it doesn't seem to be such a problem.

Let's put this conversation to bed. Nobody is ever going to agree.

lets get back on the task at hand.

[wparsons]

The only way that a higher C battery will blow an ESC when a lower C pack didn't is when the motor wants more juice than the battery can supply, and the amount it wants is enough to blow the ESC. When you give it a battery that can supply that amount of power the ESC can't take it.

On the other hand, your batteries aren't going to last long at all if the motor is constantly trying to draw more current than they can deliver, AND it can also blow an ESC with the ripple currents.

The ESC should be able to handle more amps than the motor will want, and the batteries should be happy delivering more amps than the ESC can handle, that way everything is happy running together.

As for needing a 60a esc in something this small, thats overkill unless you're way over propped on a high kv motor.

[Phaleronic]

Maiden voyage today in the canal, I ran a 2200mAh 25c pack and the boat is a screamer, thanks Jim! It also self righted twice (hatch was taped, but I haven't put foam in yet). No videos as I didn't have a helper. (edit)-Jim, what would you do to improve top end performance of the boat? Thanks. :)

Decals arrived today too. :D

[sailr]

Good to hear she's running good for you! I'm surprised it self-righted as the cat really isn't designed to do that like the Velocity Mono will.

[sailr]

Sailr, as you recall I have purchased a Mini Eco from you sometime ago. I have been running a sky lipo 3000 mAh 30c/ 60c burst. I have had no issues with the esc blowing. The temps stay around 100f. I think the esc it's self doesn't care about the "C" ratings. Its more the caps not being able to cop with voltage changes while running the boat. If you use a lower C rated battery the voltage changes will be larger (= more heat) then if you used a higher C rated battery (= less heat). I add caps to my MeanMachine's esc to cop with this voltage change and it brings down the temps on the caps as well. That being said, the 45c lipos are going to have less of a voltage change, so why are they blowing? What part on the esc is going up in smoke? Also take into consideration that the new 4 pole motors are going to be way more efficient then the 2 pole motors. Repeated on/off throttle also causes extra heat in the caps. Let me throw another brain teaser at you, if I were to use a 25c 2200mAh lipo, that would be 55 amps continuous, which is higher than the 30A, or the 40A for that matter, rating of the two esc's in question. Lets take this a step further, the burst of those lipos is likely to be at or above the 30c mark (depending on the lipo of course), so what is causing the problem? It is for these reasons that I cannot see the "C" rating being the cause for the esc's magic smoke. I hope someone else can give a better insight because this is an interesting discussion.

Apples and Oranges! The C rating determines what the battery is capable of delivering. It has nothing to do with what the motor is going to draw or the esc is going to react to. Regardless of the C rating of the battery, 25A draw from the motor is still 25A!

[Brushless55]

That's right, if a motor is only pulling 25a through a 30a esc, it does not metter if you use a better and higher c rated batter... it won't blow
If the esc does blow, something is up and it has nothing to do with higher c rated packs...

[sailr]

Ah Jeeeez! One more time. The initial surge out of the higher C rated packs blow the FETs in the original 30A Tenshocks. Forget it, I'm tired of arguing about it. The FACT is it happens. I don't give a rat's behind why!

[Brushless55]

initial surge?????
like you said, the motor will only pull what it needs, you wont have a HUGE sure if the motor does not need it!!
if it's only pulling 25amps then that's all it's pulling
lots of esc's out there that handle way more amps than what is posted on them and they can take High C rated packs without any issues at all
Ah Jeeeez! sounds more like junk caps than anything else

[Phaleronic]

First video:

http://www.flickr.com/photos/valtoninc/5893355838/

[sailr]

Look, I try to be honest with my customers by telling them that anything above 25C will blow the esc. Junk caps, bad FET's, whatever! We have now fixed the problem. Give it up!

[sailr]

Glad you enjoy our little Cat! The little guys really boogie!

First video:

http://www.flickr.com/photos/valtoninc/5893355838/

[Rich]

First video:

http://www.flickr.com/photos/valtoninc/5893355838/

That thing is COOKIN'! Enjoy that boat, like I enjoy my Eco!

[sailr]

F.Y.I. we have ONE Velocity Cat left in stock at the sale price of $209. We will NOT get any more like this. The boat has been redesigned. Not as cool looking but supposed to be faster/more stabile. I can't imagine how. WE shall see! We probably will not have those in stock until Late August, early September.

[Dustin Sontag]

I will post a video of my little v-Cat when I get the drive line issues sorted (self created).

I will say.. It is fast. Mine is almost too fast.

I am running the following:
ESC 120 amp
Stock 3000kv 2 pole motor (no heat issues)
6S 45-60c 1350 mah
stock prop

Best speed on radar was 64 mph (no where near WOT), next pass i twisted the stock drive line when I went WOT at 55mph. It held for 3 days of test/ tune / play.

Video coming soon.



Due to my addiction i also picked up the last Samurai. I will tinker with it and see what come up. Im thinking 12S and a hydra HV 240.........

[wparsons]

You're revving that stock motor to about 65k rpm? The 120a esc is probably overkill since your battery can only give 60a happily.