700 9.6v neodym fries esc
 

Hi, please help. I habve a graupner 700 9.6v neodym motor and a ripmax seasprint esc, details below. I connected all up for the first time, all connections are 100% sound and correct, bench tested for approx 2 mins all ok. THen was esc is finished!

What has happened here? why did the esc start the motor when it was turned off (you have to have a seperate 6v supply for the esc, there is no bec,) even this was turned off!


Specifications for esc, from Ripmax:

Use Boat
Operation Forward/Neutral/Reverse
Break -
On-Resistance 0.003
Frequencyf 4K
Max Peak Current* 940A
Max Continuous Current* 280A
B.E.C No
Input Voltage 6-16 cells
Motor Turn 12-36
One Touch Setting Yes
Temp Cut-off Yes
Water Cooling System Yes
Wire Size 2.5mm2
Case Size 52x35x16mm
Weight 56g

and the motor:

Graupner Speed 700BB Turbo Neodym (6306)
High-quality SPEED electric motor with neodymium magnets and a 5-segment dynamically balanced armature. Standard features include ballraces, 1.1 mm thick stator ring and an internal cooling fan. This new motor gives outstanding results in electric racing boats with 12 NC cells for the HYDRO II class using a 39 to 42 mm diameter carbon propeller.

Specification
Nominal voltage 9,6 V
Operating voltage range 7,2-19,2 V
No-load rpm 15750
No-load current drain 2,17 A
Current drain at max. efficiency 15,93 A
Current drain when stalled 117 A
Max. efficiency without gearbox 77 %
Length of case, excl. shaft 66 mm
Diameter 45 mm
Free shaft length 7,5 mm
Shaft diameter 5 mm
Weight 353 g
Part No: G6306

any help appreciated
Thanks

RE: 700 9.6v neodym fries esc
 

Hi,

That ESC has some utter nonsense specs regarding current draw (Max Peak Current* 940A Max Continuous Current* 280A ), these values are factory specs without any load...

What worries me is this: Motor Turn 12-36; as far as I know the 6306 has 7 or 8 turns, which draws more than the ESC can handle, hence the 'poof'...

As was going to check on the Graupner site, but it is down for maintenance at the moment.
Did you watercool the ESC during the benchtest?

Regards, Jan.

RE: 700 9.6v neodym fries esc
 

Hi Jan,

I was hoping you would see the post, ever helpful! I cannot find anywhere the motor turn thing with the graupner, I dont really know what this means, you would think graupner would state the turns with the spec, they dont even have an email or phone number on their website, or at least one I can find! Let me know if you find anything, it was not watercooled, it literally ran for no more than 20 seconds, at not much more than a quick 1/2 throttle blib.

Cheers

Paul

RE: 700 9.6v neodym fries esc
 

Motor turns really have little meaning when concerning motors. ESC's usually provide a turn limit as most motors around the 540 size are spec'd in turns. A better motor performance indicator is size of the motor and kv.

What concerns me is an 11 turn motor will draw about 40 A continuous on a good day. The ESC is spec'd to have a 280A continuous rating. This is 7 times higher than an 11 turn motor yet the ESC can not run the 11 turn motor? Hmm

A 700 motor on 12 cells 4s lipo will usually pull around 35A or so. This leads me to believe the 280A continuous is more like a 30A continuous.

Ryan

RE: 700 9.6v neodym fries esc
 

Hi Paul,

I tend to agree with Ryan on the ESC specs.

However, it should hold up on a short test 'blip' as an unloaded 700 doesn't draw more than 30A, maybe the half throttle setting did the damage, as the ESC will heat up much more.

I'd contact the supplier and see if you can get another on warranty, you may have gotten a dud...


I have been running a 700 Neodym on a (custom watercooled) Jeti JES 350 on 12 cells, turning a 45K Graupner prop for years without any problems, if the Ripmax ESC can handle the same current, it should function aswel.

Ask Ripmax how much A it will/should handle.

Good luck!

Regards, Jan.

RE: 700 9.6v neodym fries esc
 

Thanks Ryan, so do you think the neodym is 11 turns, and the esc stated figures are rubbish, and is really 30amps?

Jan, wtat esc would you guys use on this motor? I rang a supplier of these motors earlier, he says I need a 40 amp esc, but only had forward only ones, I need reverse, and cant afford to pay a fortune for it. I also spoke to Ripmax, didnt really want to know, saying return to vendor, but unfortunately I am already at war with the vendor about other things! Ripmax finally conceeded, and said sent it for investigation only, but even if I get a new one, the same problem will be there, they DEF will not accept another fried esc, he already is trying to blqame the bopat, which incidentally ran fine earlier on a 12v Mtroniks esc and a 12v nimh, just not quick enough!

RE: 700 9.6v neodym fries esc
 

The "11 turn" motor was just an example.

The Jeti Navy 600 sold on Offshore electrics. Reverse is useless on a fast electric hull, go with a forward only ESC.

Ryan

RE: 700 9.6v neodym fries esc
 

Hi Paul,

The Jeti Navy 600 is a good ESC, don't know what you'll have to pay, ordering from the US (while Jeti is a Tjech company...), but if you have reasonable soldering skills, this ESC runs flawlessly in my 12 cell set-up:
http://modellbau-regler.de/xtcommerc...8nj0vaqbjouh86

The Fets can be watercooled, simply by soldering on a brass pipe, (ask for pics if you want to do that, as there is a snag) and with the BEC disabled, it can handle up to 16 cells.
Very smooth response.

Next to that, there are more (flight) ESC's that will handle a 700 Neo without any issues.

I agree with Ryan, having reverse on a FE is the best way to sink your boat, running backwards (been there, done that).

Regards, Jan.

RE: 700 9.6v neodym fries esc
 

Thanks guys,

I think its the ripmax esc that is the problem , looks like the quoted spec is a load of rubbish and the motor is just too big for it. I will argue the point with Ripmax and try and get a refund/replacement, then go get another one. I know what you mean about reverse, cannot make my mind up as the boat is not a racing boat and reverse would be nice, but running would be better, and its not doing that at the moment! Its a heavy old ply boat that needs to get on the plane, and the brief run on 19.2v was really fast for this boat, so I dont want to compromise on the volts down to 12v, it does not perform at this voltage.

If anyone stumbles on the turns of the motor, please post

Thanks
Paul

RE: 700 9.6v neodym fries esc
 

Hi Paul,

Any chance of some pics of your boat?

The ESC in the link I posted can handle 16 cells, so that's no problem, but, it doesn't come with reverse, there are ESC's on the same site that do, but I would shop 'locally', as these are very good, but also not cheap.
This one for example:
http://modellbau-regler.de/xtcommerc...8nj0vaqbjouh86

Regards, Jan.

RE: 700 9.6v neodym fries esc
 

Hi Jan, i will post a very short vid of the boat and some pics when home, youtube and photobucket are filtered in work! That link you gave me, was it in German? Us English are an ignorant bunch, all I could do was look at the pics!

RE: 700 9.6v neodym fries esc
 

Well, I wouldn't call it ignorant; but with such a large reservoir of boating experience and manufacturers, 'next door', we Dutch can't afford not to be able to understand and speak German...

If you want information about the ESC's in the link, you can send them a mail, knowing these guys, you'll get an answer in English. The latest generations of Germans are starting to look over the hedge bigtime and usually know their foreign languages.
http://modellbau-regler.de/xtcommerc...8nj0vaqbjouh86

Top box: Ihre Name (Your name)
Second box: Ihre eMail-Adresse (Your mail address)
Third box: Ihre Nachricht (Your message)

If that should fail, ask me, I'll translate (more).

Regards, Jan.

RE: 700 9.6v neodym fries esc
 

god could you imagine 940amps!, that's like a powerline substation. that's like 3 houses worth of power. lol. boat would be glowing....I'm sorry it just got me laughing

RE: 700 9.6v neodym fries esc
 

I have a Hobart 220V Ironman Welder (A humongous industrial machine, weighs 300lbs), on the top end, its good for 250amps! LOL :D

RE: 700 9.6v neodym fries esc
 

I've got a Hydra 240. It weighs about 6 oz and is good for 240Amps brushless.

Ryan

RE: 700 9.6v neodym fries esc
 

similar specs :D

http://www.amgassociates.com/images/page3.jpg

FEATURES:
The POWER KING is a 28 volt rectifier, designed for in hangar use or aircraft starting. (14 volt switch optional)

* LOW PROFILE
* ALL ELECTRIC, QUIET, NO FUMES
* 2400 PEAK OUTPUT #60 HZ
* 1000 AMP CONTINUOUS #60 HZ
* 1800 AMP PEAK OUTPUT #50 HZ
* 800 AMP CONTINUOUS @ 50 HZ
* REQUIRE MINIMUM 50 AMP #208 VOLT SERVICE
* AC INPUT THREE PHASE 50 OR 60 CYCLE 200 TO 600 VOLT SERVICE (strappable in the field)
* TRANSFORMER DESIGNED TO GIVE MORE DC OUTPUT
* RIPPLE and RFI FILTERED
* REVERSE DIODES
* SOFT START DESIGNED TO PROVIDE MINIMUM STRESS ON AIRCRAFT ACCESSORY DRIVE SYSTEMS (optional)
* OVER VOLTAGE PROTECTION
* CABLES STANDARD EQUIPEMENT: 100 FT. AC INPUT, 20 FT. DC OUTPUT (no extra charge)
-
in all seriousness I'd ask for my money back, based on false advertisment, all the sites I can find that esc, rate it at 940amps... utter bs, I'd call them right up. You might want to leave out how many turns your motor has, but really you say 940 amps and some people take that as truth, so by that logic, of course a 700 series motor "should" work. Now honestly looking at a picture of that esc, I'd never hook it up to a 700, but this is a trained eye. False advertising...nuf said.

RE: 700 9.6v neodym fries esc
 

In my opinion they have left out a "point" in the current values. A bad typo if you will.
Perhaps it should read ...
Peak 94.0 Amps
Continuous 28.0 Amps.
I bought an ESC for $16.00 that was rated at 200 Amps forward & 100 Amps reverse at 7.2v. Knowing that it could not be right, judging by the tiny wires & cheap plugs on it in the advertising photo, I bought it anyway to test it out.
As suspected the specs should have read 20.0 Amps forward & 10.0 amps reverse. It is in no way a 200 Amp ESC.
But for $16.00 it did the job that I bought it for. Gets moderately warm at 15.0 Amps (not water cooled) on 7.2 V.
But yes... it is false advertising.
This is the one
[link]http://www.r2hobbies.com/proddetail.php?prod=rcps81710[/link]
Cheers.
Paul.

RE: 700 9.6v neodym fries esc
 

Here is the boat, a 36" ply RAF Fire tender, originally built 1960, just had its 2nd refub, and the black/white photo is the original, they where designed to support Princess seaplanes, but never relly saw much service. 2 Boats where built, "93" and "94"

Thanks for all help and advice, I did call Ripmax today, and questioned the massive figures stated, and asked was it milliamps! but they where adamant they are correct, so I am looking on ebay for a disused Formula 1 engine.....