I SCREWED UP... PLEASE HELP (who can repair ESC's?)

[Adam Lee]

I believe my SWORDFISH ESC was damaged when a cheap EC3 failed during a high speed pass. Power to the ESC was lost while the system was under load. Can anyone please tell me if my ESC is repairable and IF SO, how should I proceed? (Who can repair this??)

Here's my set up:

Delta Force 29 mono

Dynamite A3630 1500KV 6 Pole brushless marine motor

Swordfish 200A PRO ESC (4-8S Lipo) with 6mm gold plated bullet connectors for battery and motor

TWO - Floureon 4S 4500mah 45C batteries with EC3 connectors; connected in series to make 8S

electrical harness with EC3 battery connectors and 6mm bullet ESC connectors

running Traxxas 42mm (TRX42) prop at the time of failure.


Thank you in advance for taking the time to read this. Believe me, I have learned my lesson and welcome any advice or criticism you care to offer. I chose the EC3 connector for convenience. Its what I happen to use on most of my other vehicles. It is clear that this connector is not acceptable for high power boats. Expensive lesson!!!

[Doby]

8S on 1500 kv motor is around 44K RPM unloaded...42m m prop on a small motor like that = Lots of amps..

Your connectors were the least of your problems.

Your ESC is FUBAR'd....time for a new one, less voltage and a smaller prop to start with then work your way up.

[Fluid]

The connector failed because the amp draw was excessive for the system. That small cheap motor saturated its coils producing no additional speed, turning the rest of the power into heat. If it got too hot on earlier runs the magnets are probably toast. Bad magnets can roast an ESC...ask me how I know.

ESC damage can be cumulative too, it could have been damaged on earlier runs and finally quit on the last. You can safely run 8S in a small boat like that - I've done it many times - but you need a slightly larger motor with a much lower Kv. Find one with a Kv around 1000 - 1200 and you should be good to go. You will still have to make reasonable prop choices and not run the boat too long if it runs a bit hot.



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[JimClark]

EC3's are rated at 60 amps continious

[ray schrauwen]

The connector failed because the amp draw was excessive for the system. That small cheap motor saturated its coils producing no additional speed, turning the rest of the power into heat. If it got too hot on earlier runs the magnets are probably toast. Bad magnets can roast an ESC...ask me how I know.

ESC damage can be cumulative too, it could have been damaged on earlier runs and finally quit on the last. You can safely run 8S in a small boat like that - I've done it many times - but you need a slightly larger motor with a much lower Kv. Find one with a Kv around 1000 - 1200 and you should be good to go. You will still have to make reasonable prop choices and not run the boat too long if it runs a bit hot.



.

Re: bad magnets. Can a motor feel fine and still have weakened magnets? I have one motor that may be a little off, heats up like a bugger same as esc but batts don't sweat at all.

[raptor347]

Re: bad magnets. Can a motor feel fine and still have weakened magnets? I have one motor that may be a little off, heats up like a bugger same as esc but batts don't sweat at all.

Yes they can. Every time you get them too hot, they degrade a little. So as the magnets degrade, it effectively increases kV causing even higher current draw and heat.

That's why you look for higher temp ratings on magnets.

[Adam Lee]

Thank you very much for the replies. I was under the impression that more cells equaled less current draw. Volts up = current down. is that not the case? Regardless, I've learned several lessons here. Thanks again!!

[raptor347]

More cells without changing motor or prop will dramatically increase your current.

[Adam Lee]

I've got a lot to learn...