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I have a 24v 500w scooter dc motor. I'm using the scooter controller. It has forward, reverse and throttle control. I'm using a joystick controller connected to an Arduino, controlling the speed and dir of the scooter controller.

I'm trying to use the arduino to do current reverse braking to slow the motor to match the position of the joystick. I don't want it to let the motor cost.

I'm not sure if current reverse braking is the best way to control the speed of the motor.  If it is. How do know how much current to send it so it slows with out damaging the motor...


Thank for any help or ideas! 
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I have a 24v 500w scooter dc motor. I'm using the scooter controller. It has forward, reverse and throttle control. I'm using a joystick controller connected to an Arduino, controlling the speed and dir of the scooter controller.

I'm trying to use the arduino to do current reverse braking to slow the motor to match the position of the joystick. I don't want it to let the motor cost.

I'm not sure if current reverse braking is the best way to control the speed of the motor.  If it is. How do know how much current to send it so it slows with out damaging the motor...
 

If this is a brush type motor, which would be the case if there are only two wires going to it from the Controller.  At 24V, a 500W motor will draw roughly 20.83 Amps which means when you put "reverse braking" into it you should only exceed that current for a short time.  If you don't, you will damage the motor. Does it presently have any braking at all, like tying a resistor across the motor?  What would be the cat's meow is to channel that energy back into the battery.  Do you have or can you get a schematic of the Motor Controller?  It would be nice to know what is there so we can determine the best way to hack it.
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What  rmetzner49 alludes to here is removing power from the motor and placing a load across the motor's terminal, allowing the motor to act as a generator and the load will slow the generator. Also alluded to is regenerative braking where by the 'load' across the motor is eventually the battery, charging it. - Scotty 
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Very good, Mr. Scott.  You must agree though some idea of what is already available in the controller would be nice.  I hate the idea of something as RUDE as a relay that disconnects the motor from the controller and places the resistor across it.  It's "a way", but we don't have any idea what the controller will think about having its load interrupted like that.
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I have a 24v 500w scooter dc motor. I'm using the scooter controller. It has forward, reverse and throttle control. I'm using a joystick controller connected to an Arduino, controlling the speed and dir of the scooter controller.

I'm trying to use the arduino to do current reverse braking to slow the motor to match the position of the joystick. I don't want it to let the motor cost.

I'm not sure if current reverse braking is the best way to control the speed of the motor.  If it is. How do know how much current to send it so it slows with out damaging the motor...
 

What model is this motor controller?  They are usually programmable for such settings as
acceleration and deceleration rates and soft/hard braking.

If this is a brush type motor, which would be the case if there are only two wires going to it from the Controller.  At 24V, a 500W motor will draw roughly 20.83 Amps which means when you put "reverse braking" into it you should only exceed that current for a short time.  If you don't, you will damage the motor. Does it presently have any braking at all, like tying a resistor across the motor?  What would be the cat's meow is to channel that energy back into the battery.  Do you have or can you get a schematic of the Motor Controller?  It would be nice to know what is there so we can determine the best way to hack it.
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Might I suggest you look at the 4QD website where you'll get loads of technical help with regards to regen braking
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It doesn't have any kind of braking attached to the motor. The controller is chines and lacks any kind of details, except the throttle, power motor and poet light cables are labeled! I'm not to worried about capturing any power back at this point....

So when I'm trying to slow the motor...  Should I hit it with the max speed in the opposite directs for short burst or try to figure out the current speed and hit it with an equal amount of power?
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Is this about a brushed motor?

It probably shows that I'm not The Motor Maven, but isn't the motor voltage supposed to be disengaged and then a (variable) low resistance placed across the windings (terminals)?

If the scooter coasting keeps the motor spindle turning then - it's a generator (yes?).

> > > I've only ever done with a free-wheel so, I'm more asking than pronouncing.
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Exactly, Pancake.  I already suggested in an earlier post he shouldn't go above 20 Amps for braking.  An SPDT relay good for 30A, and a 1 ohm resistor,  Center term. of relay goes to motor, outer terms, one to Controller, the other to the resistor.  Can we energize the relay when you "step on the gas"?

Now for the sad news.  Since it's a 500W motor, you will need a 500W resistor  unless you want to use a 100W and use it for a tail light.  LOL  That's why it's not such a bad idea to throw it back at the battery.
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Right, right.
I was getting the read that our friend here is figuring on "injecting" a reverse current to counteract or other.
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