I would like some clarification on the safety of my efoil under construction on the correct connection of a kill switch. I have the 65220 motor with 2 outputs in addition to USB, PPM and UART. The remote control is connected in UART and the motor also has the PPM cable in the vesc I enabled the two ports by setting the software to High. But I would like to be sure on how to use the kill switch? Someone told me about putting a 10k resistor between ppm + 5v and ground. Could you explain to me if any of you have experience with my configuration?
Simply put, you always want to have the killswitch input pin to the VESC at a defined level.
Lets say you have a killswitch that connects that input to GND (0V)
When that switch opens, the input will “float”, so not be at any defined level
So you should also connect a 10k resistor from that pin to 5V, which will pull the pin to a defined state (5V) when the switch is open.
That only works, if you have acces to BOTH the PWM/UART and ADC pins, because the killswitch input needs a separate pin. Either the PWM pin when throttle is commanded through UART or the ADC pin when throttle is commanded through PWM
The 65220 motor+vesc combination does not have that, in only routes out the PWM signal and USB I think…
So in that case you will need additional, more complex hardware
For example a digital switch, transistor or similar, that lets you intercept and disable the PWM input to the VESC when the killswitch is open
One simple solution: Get a normally-closed killswitch and put it inline with the supply voltage of the remotes receiver
This way, when the killswitch is pulled (open) the supply to the Rx will be broken and the VESC will stop the motor, as it does not get any signal from the Rx anymore
EDIT: The new version of 65220 seems to have UART and PWM
In that case, connect UART to the receiver of the remote and do throttle control through this
Connect killswitch from GND to PWM pin and a resistor from 5V to PWM pin
Then select App Settings >> General. → PPM low or PPM high depending on your switch
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AOkay, good thanks. Isn’t there a risk that the motor will stall or accelerate when I reconnect it to restart?
So to recap 
I connect a 10kΩ resistor across 5V to ppm.
I connect a magnetic switch with a leash between ground and ppm.
I set the vesc kill switch to high.
The motore flipsky 65220 not have gpio pin esc is integrated .
Trial Connector uart And ppn And usb
Not sure if I understand the question, but the motor will only start if killswitch is there and UART commands throttle (you give throttle input)
Correct. Maybe killswitch set to “low”, not sure how the internal logic works, but this will be easy to try once you have built everything
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Ok with the leash inserted on ppm it gets low so everything should be normal. With the leash removed a high signal should get on ppm so the vesc should cut off the motor. I’ll try and let you know.
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If I decided to use only PWM (PPM) basically if I connect a magnetic kill switch (normally closed) directly to the positive or negative wire + KILL + if I were to disconnect it apparently it cuts off the motor. right?
You should still add a resistor like in the image above, so the level on that input pin is always defined
I simply tried disconnecting the PPM + - S pins on the receiver and the motor shut down. Why do you also recommend the resistor?
To pull the input to a defined state and not leaving it „floating“, this is best practice.
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Exactly
The VESC probably also has a resistor inside but I would not trust that too much
Let’s say you have a bit of moisture on your kill Switch conducting a tiny amount of electricity, even if it opens, if the output is not pulled to ground by a resistor it may still have the PWM signal present
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Ok thanks for the advice, I’ll try to assemble a resistor and do some tests.
@MaseSaturo how do you like the 65220? i am considering this setup on a efoil project i am planing at the moment. do you think it will handle continous use over time? Or do you think it will have cooling/heating issues?
Do you mind sharing more of your build? I would love to see some pictures of this motor on a mast to see the dimensions