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Electric wheel chair, question about amps

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joshua17ss2

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i got an electric wheel chair, and ive been working on modifying it, i think that the original motor control is totally dead, so im working on desinging my own.

The motors are 24 volt DC motors. their are 2 12 volt 50 amp batteries.

my question is do the motors actually run on the 50 amps, or is that more for longer battery life ? Maybe only uses 50 when loaded down with a person, or something like that.

i want to find 24 volt 50 amp RC ESC w/ reverse but my time spend on google has given me few results.
i would also like to know if either there are ESC that would meet my needs, or if i could use a much lower amp ones.
any information would be appreciated.
 
There is no such thing as a 50 amp battery.
50 amp hour maybe, it has nothing to do with the motor itself though. 50AH's means it will provide the equivalent of 50 amps for 1 hour. BUT amp hour ratings on lead acid batteries (what you're using) are based on a 20 hour discharge. So you can only draw 2.5 amps off that battery and still get a 50AH rateing on the battery. More than 2.5 amps at a time, and the capacity is lower from internal losses. You need to determine what the TRUE current draw under a typical load is going to be for your motor before you can determine what kind of ESC you're going to use.
 
i got an electric wheel chair, and ive been working on modifying it, i think that the original motor control is totally dead, so im working on desinging my own.

The motors are 24 volt DC motors. their are 2 12 volt 50 amp batteries.

my question is do the motors actually run on the 50 amps, or is that more for longer battery life ? Maybe only uses 50 when loaded down with a person, or something like that.

i want to find 24 volt 50 amp RC ESC w/ reverse but my time spend on google has given me few results.
i would also like to know if either there are ESC that would meet my needs, or if i could use a much lower amp ones.
any information would be appreciated.

The Web tells me 5 hours of W/C operation between charges is reasonable so this would put motor current draw at ~10A.

To measure max current I'd load the chair with 300# and go up a wheelchair access ramp; these ramps are designed so that most or all W/Cs can go up it.

The reliability of your control circuit must be very high because a life depends on it.

If the rated motor current is I and you use PWM for the motor control, exceeding 5I will probably demagnetize the motors.
 
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You can't really specify the load requirement for a motor, because it varies massively over it's range of use - but consider a much smaller, far less powerful, motor in an R/C car can easily take over 100A on peaks, and needs a substantial ESC.

For reliabilty reasons alone I would suggest you replace the controller with the correct type, unless you're just ripping the motors out to make a robot wars type machine?.
 
Robot type war machine is about how i would describe it. im shooting more for simple Robotic base.
i still have the original motor controller, and im still trying to bring it back to life, im waiting on a new hex inverter chip as i think due to a wiring mishap it got burnt up.
so im gonna replace it, and try again, i already bypassed the brakes on the motors, so they now turn off when the power is applied for now. i just want to get the wheels turning again.

At the moment i just want to get the whole base responding to an RC remote. then move on to a computer.
 
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