10,000 MaH ?!

[ncornacchi]

Ok, to beat a dead horse, here's my question: My friend is running a mean machine with a Nue 1515/1Y, CC240LV, M440,2-2S in series (4S 5,000MAh, 25C total) When he first ran his setup, he blew the caps right off the ESC. He got a new one back from Castle, and now his boat runs for a minute or two, shuts down, then starts up, then shuts down (LVC is set at 12V)...when he called Castle, they keep telling him that he needs at least 10,000MAh...Now I'm no rocket scientist, but I can tell you that I am running the exact same setup in a UL-1 with a M445 and I get 4 times the run and no stutter or shutdown on the same batteries with never any problem! So what could be wrong? Should I advise him to get 2-4S 5,000MaH and run them in parrallel? I know that he's not over-propped (I've actually used a M647 on mine, but it drops the RPM's down too much and I knew that it was pushing it), but I kind of am at a loss as what to advise him, especially when castle is telling him he needs at least 10,000MaH....Any of you gurus got any sound advise or feedback? I don't want him to get to frustrated, plus I want the UL-1 to kick the MM butt when he finally gets this thing dialed in...Thanks to all !.....Norm

[Rumdog]

He may not need 10,000 mah. 4s1p at 5000mah and 25c is only good for 125 amps constant. I'd runrun 4s2p, or packs with a greater c rating. I really don't think that his esc should have went though. Especially with that small of a prop. Find out how deep his strut is. He could be overloading the prop, or have a wet running hull.

[Fluid]

There is nothing 'wrong' with the ESC. Catamarans have significantly more drag than hydroplanes do, and they simply can't run the same setup without risking overheating. With both boats running an optimized setup, the hydro will win in the speed department every time. Just check the SAW speed records in NAMBA and IMPBA.

I am certain that your friend is drawing far more amps than you are, no surprise there. His setup is pulling down the pack voltage because the cells aren't strong enough to deliver - this stresses the ESC and causes eventual failure. He needs to reduce the amp draw with his 1P setup or he'll continue to blow ESCs - trim the hull looser, raise the prop, something. A better alternative is to change to a 45C/5000 mAh 4S1P pack, or go 4S2P with his current cells. Either way he'll still pull more amps than you will with your hydro.



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[knpc]

Norm
I don't know if you have any 4s packs for him to try, if not he could borrow a couple of mine to run 4s2p to see if that solves the problem. I wouldn't want him to go spend the money on new packs if that isn't the problem. I'll be working in Rockland this weekend (about 3 min from your house) I could swing by so he can give them a try.

Let me know

Kevin

[ncornacchi]

Thanks guys....I kind of thought that the packs were suspect (the C-ratings suck) and I knew the hulls were the difference. I'm not saying that the ESC is bad, but I couldn't believe the 10,000MaH reccomendation from Castle....Kevin, I don't have any 4S packs, but if you're around this weekend, stop on by the pond, I'm sure that Joe will make himself available...He's using 5.5 bullets, so if you are using 6mm bullets, let us know,,,, we should tell him to make up a parrallel harness to try your batts....

[knpc]

Norm - my packs have 5.5 bullets and I have parrallel harness he can use. All my stuff has a male and the red and female on the black coming off the esc, as long as his is the same it will plug right in.
I'll stop by this weekend, sat or sun afternoon. whatever works for you guys.

[D&D]

While I still consider my self a "newbie" when I was even newer to the hobby I read so many different opinions in different forums that I finally wrote Castle the following e-mail and got the following reply: (It applies to the above)

I am new to electric R/C boating and purchased a Hydra HV 180 ESC,I have a couple of questions concerning this unit:

1. When I read the R/C boating forums everyone talks about heat as the big issue and everyone quotes this temperature and that temperature. Obviously the coolest you can run the better, but at what ESC temperatures are you beginning to run into trouble? Any advice on temperatures (try to run around this temperature, don’t let it go beyond this temperature, etc.) would be helpful.

2. Again with the forums, I read that a motor with this many poles should be run with this timing, etc. When I read your manual the settings clearly are for most run time, most power, etc. and does not seem to account for type of motor (I have a NEU 1515.1Y). As a Newbe I just want to check that the timing for my engine should be set as (for example): 2 – Best balance of power and efficiency. Recommending setting and forget about the number of poles my motor has? When I look at CastleLink the timing settings are not listed as (1, 2, 3, 4) in the Manual. Guess I just need some general advice in this area.
Thank you for any assistance you can provide.
Dennis,
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REPLY FROM CASTLE:

1. With a water-cooled ESC Heat is not a big issue. What takes out ESC in high power systems is inadequate batteries. If you check you boat/motor application chart you will see the minimum battery size is 8,000 mah and goes up to 16,000 mah. This takes 2 packs in parallel to achieve. Anything less than this, or cheap, irresponsibly labeled lipos, will kill the ESC quickly.
2. Motor timing is a little deceptive. On other motor types it has an affect power and heat. This is regardless of pole count which is somewhat of a red hearing. What maters is motors inductance but since this measurement is not provided or should it be trusted if it is given there no way to really know. Rule of thumb, the lower the turn count of a motor (higher the Kv) the lower its inductance. On these ESCS motor timing is dynamic and changes with the speed and load on the motor to maximize the efficiency of a motor at any speed. Raising or lowering timing has a small affect on power and a huge affect on heat. On motors, you do not want them running over about 170 degrees f. If the motor is over this at normal timing decrease timing to cool it off. A Y wind Neu motor like yours usually works best at normal timing #2. You would only run high timing if you need every last second of speed and don’t care if the whole system catches on fire. With a D wind Neu motor you MUST run low timing, #1. D wind motors do not respond to timing but at anything other than low can damage an ESC or batteries.

Bernie Wolfard
Product Support
Castle Creations

[ncornacchi]

Joe, You should hookup with Kevin to find out when he'll be around...I will be in and out all weekend and it will be a crap shoot wheather I'll be home or not, but feel free to use the yard...I hope that I'm around because I still want to pit the UL-1 against his Df-33!