I like to know if pushing the board for longer distances is ok or not. I think it should not be a problem if the VESC can regenerate to the battery, isn’t it? But what will be happen if I turn off the board and the VESC can not feed the battery?
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Nothing. There will be only small mechanical resistance. That’s all.
Just be aware: that the faster you go - the higher the voltage on the motor will be. If it reaches certain ( high ) voltage, it can blow up your ESC. That’s not very likely tho. I don’t know how VESC works, that’s just my general knowledge of motors.
The motors will turn on the vesc if they are connected. If the batteries aren’t connected and u ride that’s very dangerous as the motor energy will either ruin the vesc or slam on ur brakes. Keep batteries connected if pushing.
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Thank you, that’s what I thought. So I will have my batteries connected if pushing.
@Hummie Do you have a sense of how much speed (and for how long) this would require? My impression (and it could be totally wrong) is that the energy generated and delivered from the motor is pretty small.
Everybody should learn at least Ohm’s law… Guys, there is no energy that “has to go somewhere”.
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The motor will generate enough going even over 5mph it can slam on it brakes. That’s if ur lucky and it doesn’t blow up ur stuff. Or maybe in my case it was better. Happened a couple times to me before I found out what was up. The energy has to go to the battery or else it’s forced to dissipate in the esc and poof
I’m not convinced on the large danger of this. While I agree it can create some electrical activity in the motor. I don’t think it creates enough to damage anything and will most likely dissipate that energy as heat.
I suppose someone could disconnect the phase wires and hook them up to a meter to measure current and voltage through them when traveling.
There is a voltage on the motor, no magic energy flowing out of it. If there will be any current ( energy flow ) depends only on the ESC itself. There don’t have to be any current ( open circuit ) and motor can spin freely. Or there can be very small current just to keep the VESC running ( unnoticable for you as a driver ). Energy is produced only if the motor is converting kinetic enegy to electron flow - it don’t have to do it. Once it does, you can feel it ( you loose your momentum ) - it can be really small so you won’t notice it. If it breaks - then there is problem. Breaking means most of your energy is transfered to the flow of the electrons and if that happens, there is a huge current flowing through the ESC that can burn it. That’s it. It’s not like water or anything that has to go somewhere and get stored. You CAN’T store electricity. You can transfer it to chemical energy ( battery ) and than the other way around once needed. Electricy is movement of electrons inside the wire in a loop. Those are the basics of electricy.
So, will it blow your ESC? Really depends on how it’s designed. I don’t know how VESC circuitry works, but what causes damage is the current flowing through something.
I won’t recommend doing that anyway.
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Check vedders site on the details of how much energy is produced when coasting and no batteries and when it will ruin the vesc. I had brakes slam on at 6mph
Is all of this discussion referring to riding with a dead or turned off battery, then? When the system is on there should be no issue at all, and it’s totally fine to coast at high speeds, right?
Referring to having a battery connected. If the motor is connected to the vesc it will power up regardless of if there are batteries attached. If there are no batteries attached it’s dangerous
The only problem I see with connected battery is if the battery is completely charged and you additionally generate energy into the battery while pushing for longer distances, so you can overload it.
You don’t charge by pushing only braking. Going down a hill and braking with full charge u can overcharge the battery
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Ok cool. Who’s gonna push with a full battery, anyway? 
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@Hummie: Exactly. Actually, you do transfer little bit of your momentum to electricy so the VESC has some power to operate, but that’s unnoticable. The moment when the ESC allows electrons to flow and convert mechanical energy ( your kinetic energy transfered to motor shaft ) to the electrical energy is when you break. And this electron flow can either go to the battery / capacitors or short something out in the ESC ( if it’s badly designed ).
@Spek: Yup. Even if you went the hill up and then back down, you would still generate much less energy than you used to get up.
That’s good! So I can push my board with unconnected battery but I’m not allowed to use the break, right? Oh, I forgot it is not possible to break with unconnected battery.
No. must have connected battery if ur vesc is connected to spinning motor and ur pushing
OK I understand. I can not push it without battery because it’s still dangerous for the vesc, right?
Nobody actually knows how the VESC works in a detail ( well, Vedder does ). You should be fine just pushing it ( not using breaks ), but noone is gonna guarantee that. Neither me.
Do it at your own risk, in theory, you should be fine, but in reality? You will have to find it out!