I’m new to electrical engineering and am currently in the process of modding a custom electric scooter I’ve built. But I need your help.
Goal: Be able to turn on/off my electric scooter wirelessly (technology doesn’t matter, wireless, blutooth, RFID, something mechanical like a magnet?). Ideally – it’s a passive switch (no power draw from battery when it is off), and more importantly, it HOLDS it’s state. So I don’t need to hold a magnet to the switch constantly to have it turned on but just need to tap the magnet once to turn the switch on, and tap it again to turn it off. Something like that. I don’t want a physical toggle switch because of security issues (don’t want some random person to turn on my scooter while I’m away).
The other important parameter is that because this electric scooter will go over unpaved roads and high-vibration environments, it must not just click on/off easily if you hit a big bump.
Finally, the switch will be connected to a 42v lithium ion battery (10 cells) which is then connected to a Flipsky microcontroller. So the switch should be able to handle 42v / high current because presumably the direct drive motor might take in a lot of current?
Basically, is there some form of wireless passive on/off ignition switch that holds its state and meets the parameters above?
I used to use an antispark switch but after having 3 fail on me in a row, i’m going to find a different solution. Also don’t want to carry around a loop key so prefer to make my solution wireless.
Do i have the wiring correct? My only concern is that the relay is rated for 12v… and the battery provides 36v. Do i need to use a buck stepdown converter? If so, the other problem is that wouldn’t I be underpowering the motor that connects to the VESC if I’m no longer providing the full 36v of power but instead 12v only?
So you basically want a wirelessly controlled, high power solid state switch or mechanical relay, correct?
A 12VDC rated relay can work with higher DC voltages, but you’ll get excessive contact erosion and possibly glitches during turn off.
Supplying 12V to the ESC is not going to give you very much speed, and finding a buck converter rated for that much power won’t be easy.
If you want, I can take one of my existing switches and modify it to work with the arduino nano 33 ble, this should provide you with an adequate solution.
But another thing, if security is the issue, have you considered a keyed switch? The switch would then control the high power relay
If you make a Bluetooth eswitch… I’ll take like 4 of those, if they have a proper precharge circuit and reasonably low passive battery drain, can such a thing exist? I hate latching power buttons and unneeded enclosure holes.
Hey would love to take you up on that offer. But how is that any different then the schematic I posted? Do you have a special switch rated for high voltage, 120a applications? I guess I don’t understand how that solves the issues you talk about. I’m guessing the arduino takes place of that Chinese Bluetooth module, but don’t you still have an issue with the switch not being rated for high voltage and high current?
