Not enough power noob question

Build, Repair & Mod
#1

Hi,

Although I have been looking at the information here for a long time, this is my first post.

I am currently facing what I believe are power issues that I hope someone can help point out where the issue might be. When going full speed in the water my Amp draw is between 3 and 4 depending on currents, and that is very low and I would expect the motor to be pulling many more amps. Results are the same on both of my battery packs.

My gear

  • Motor - Flipsky 65111
  • ESC - FVESC Mini 70A
  • Battery 1 - LifePo4 120AH 24V BMS 80a
  • Battery 2 - Lion 20AH 48V BMS 30a

I have the motor running in FOC mode, it was set to BLDC before but it was noisy.

Project background

I am building a outboard motor for my 6ft Zodiac. I am not looking for any crazy speeds and the intention of this build is to have something that can putter me around lakes at a higher speed than a conventional trolling motor.

While this is already achieved, I am wondering if I can pull more power out of the setup since the low amp draw at full throttle seems to be the culprit.

Then again, I could be wrong and I am maxed out in this motor and need something more powerful.

Here’s a photo of what I am working on and any help or advice is appreciated!

IMG_6088
IMG_60881920×2560 363 KB

#2

Current seems unreasonably low, 3-4A is roughly noload current for a motor like this. How do you measure the amp draw?

I’d hook up the esc to a computer and check settings, motor/esc matching and throttle input to see if it’s all good.

#3

I have a battery monitor plugged in that shows me the amp draw.

On the vesc tool, when running the motor in dry air condition not in water it shows 2a as well as on my battery monitor. So that leads me to believe the value I am seeing on my battery monitor when in water

#4

On air the motor will not be drawing more then few amps cause of missing resistance.
In addition to tweak the ESC settings my guess is also that propeller is not suitable, either you cut it down or get another propeller which is more suitable for this motor.

#5

That’s my understanding too, in the air there is no resistance so the 2A draw makes sense. But it doesn’t make sense that my draw is only 4A in the water. One thing to note however, is I did hold the propeller shaft and cranked the throttle 1/4 to mimic resistance and I did see the Amp draw go up to 30a.

The propeller I am using is the one that came with the motor factory, I would assume that there shouldn’t be a problem with using it.

As for VESC programming, it’s new to me. It very well could be that I programmed something incorrectly.

#6

Did you put the pin in the prop shaft??

#7

Yes I did, I have the little thing going through the shaft and the pin at the top