Electronics help

Please help!!! Ive been reading and reading and reading… I want to build a jet propulsion motor for efoiling but I also have designs to hook this motor up to a paddle board. I have most of my designs down and and tested smaller versions with cheap motors and such and have a solid idea. Where I’m stuck is all the electronics as I don’t have much experience in this field or with RC stuff. I want to buy the right components from the start so I don’t have to spend a fortune to fix it. Okay I’m planning on sss 360kv motor or sss 500Kv motor but open to suggestions. I was going to use the 130 amp seaking ecs but I’ve seen issues with these burning up I’ve seen people talking about 300amp controllers but won’t this burn the motor up? I’m making a battery back with Sanyo cells I’m thinking 2 pacs of 6s14p so in total 12s14p I’m hoping for long rides. Any suggestions are appreciated!

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As for ESC amps this number identifies the max amp the ESC can provide. The higher the number of the amp of the ESC the better, since the ESC will dissipate less heat and more reliable in general. Indeed it has also higher price. 300a or even 400a is a good choice especially for jet purpose since jet (no gearbox?) Will consume more power then geared setup for sure


@ Mathew
@Antonbit has given the same advice as I would have given. just the other day I ordered a 400A 16s… yes it is over kill but the way I look at it is I could of purchased one half the price & replaced it with the same only to have the second fail… or go over kill & have a unit that will handle more abuse, (Disclaimer the ESC is still untested as it has not arrived) But I see a lot of logic in overkill on a ESC. I also welcome advice on this subject.

Thanks this definitely helps I’ll start looking for a higher amp ecs. Any recommendations on BEC?

@Mathew , I am looking at getting " https://hobbyking.com/en_us/turnigy-multistar-twin-output-5-10-amp-6-50v-sbec-for-lipoly.html " but it is on back order :frowning: . wanted to use the 5V for the RC & 12V for the water pump for cooling , however I may have to use a dedicated 5V BEC for RC & a separate power supply for the cooling pump so as to have constant cooling. I am also seeking advice on this matter so any other input is very welcome.

VeFoil recommended this one. https://hobbyking.com/en_us/kingkong-5v-3a-ubec.html Says when they tested it it handles 12s great.

Alex, that’s exactly what I did. I have the same multistar dual SBEC and another 5 volt UBEC as well that I have connected to the 12 volt out of the SBEC. I then have a magnetic safety switch that cuts 12 volt power to both water pump and 5 volt UBEC.

I am also looking for solution. Unfortunately that multi-star is good for up to 13S. I need 14S. I just ordered 2 of these. one for 5 volts, and another for 12 volts. Anyone try these before?

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@MAC, “Quote” “Anyone try these before?” No from me…
The pump I have is a DC6-12V R385 its claimed current draw is 1A so the 1.5A working current of the SMAKN DC is a bit low in my mind, as I think the available current of a power supply should be much higher for something critical like the cooling system. I would be guessing the 1.5A working current is not for the unit held within a sealed box that has Heat from a ESC working hard & the heat from the battery’s as well. Not sure how hot my sealed electrical box will get. so I think we should keep looking for something around 12v@ ~10A… Has anyone else got some advice of a proven 12V supply? please…

Thanks for the response. I have the same pump. I just made the following observations. The pump completely dry will self prime at least 40". Once the inside of the pump gets a little wet it will do even better.
At 11.83 VDC the pump draws less than 250 ma. If I dead head the pump it draws about 400 ma. I know that sounds like it draws very little current. I did the measurements a couple times to be sure.
I had another thought. I plan to use the same buck pwr supply to also pull in the coil on my safety relay. I measured the coil current to be 200 mA.
So 200mA +250mA= 450mA. That is well below the 1.5 Amp continuous rating. If the power supply fails it will shut down my safety relay so it won’t need the cooling pump.

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@MAC Thanks for the real world numbers, I will reconsider the need for a 10 amp that I was thinking of using & drop that down to around 5 amps. I will buy a SMAKN DC & run a stress test & see at what temp it fails at. It will take me a week or two to get the hardware so will post the results after that.

Turns out I am not happy with my purchase. I bought 2. I adjusted one for 5 volts, and one for 12 volts. I was using a 30 volt power supply to adjust them. They dialed in perfectly. I did a really nice job of solder. heat shrink, mounting. When I hooked up my 2 6S Lipos the 12 volt did not power on. Long story short, when the input voltage reached about 46 volts the 12 supply output would drop to about 7 volts with no load on the output. So Im back looking for a reliable solution for 14S input power.

FYI The https://hobbyking.com/en_us/turnigy-multistar-twin-output-5-10-amp-6-50v-sbec-for-lipoly.html is back in stock from Australian warehouse. (Not sure if that helps you).