# Help with new project



## Catch22 (Feb 21, 2010)

Hello.

I am new to your forum and would love some advice on a project I am working on.

I am building a youth riding car. This is a wood kit car that was designed to be a pedal car. I am modernizing it to be an electric car. 

I have two Hoveround MVP 4 geared motors and need to know of a reasonably priced controller that will run the motors. Would like reverse. 

I would also like information on electronic throttles. I have seen videos, of people that have used hand throttles but converted them to work as a foot throttle.

How hard would it be to wire in a reverse switch that would allow the throttle to also be used to back up?

Catch22


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## Amberwolf (May 29, 2009)

If those motors are like my Invacare motors and are brushed PMDC, you can use the http://4QD.co.uk series of controllers on them. The 4QD is a full-bridge controller and can run the motor forward or reverse with identical current either way. The 2QD (when it's available) can also run in reverse if you use two of them back to back (they're only half-bridge by themselves). 

If you use the 4QD then you just flip that reverse switch to change directions, and the throttle will do exactly the same as it did in forward operation.
http://www.4qd.co.uk/serv/appnotes/for.html

If you use a pair of 2QDs, it's a little more complex.
________
KINKY_LOLA CAM


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## Harold in CR (Sep 8, 2008)

Last night, I happened to see a Hoveround controller on Ebay.


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## Catch22 (Feb 21, 2010)

Most appreciate the help. I found the 4QD with reverse on some of the robot sales web pages. That looks promising.

I also found this web page. http://www.electronickits.com/kit/complete/motor/k166.htm

Is a unit like this, if built up, strong enough for the larger motors?

Have not gotten the motors yet from my seller, but here are the specs he sent.

Brand: Shihlin

Type: a9y1x02872

Brake Voltage: 24VDC/0.3A 6kg-m

Amp: 3.7
RPM: 188
dB9(A): 56

​


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## Amberwolf (May 29, 2009)

That "3.7A" is almost certainly just the no-load current. That's how all of the Invacare motors I have are marked. 

So you'd probably fry those kits pretty quick trying to run these motors from them.


For instance, 24V 3.6A is what my 4-pole brushed PMDC ~650W motor is marked, and during an incident where chain was derailed and jammed in the front triple, the motor continued to be able to spin the triple, reeling in chain until the rear wheel was pulled out of the dropout on the chain side, bending the axle, crushing the rim, while drawing over 2500W on 36V of SLA at a peak current of 153A (for just an instant), which was enough to actually blow up the bottom two MOSFETs of my 2QD due to my totally inadequate heatsinking. 

During regular use I could easily draw over 50A at startup from a stop (with little 2QD heating despite my inadequate heatsinking  ).


Oh, also, the 4QD series will use any 0-5K throttle control. He carries this 
http://www.4qd.co.uk/accs/pots.html#plunger
that coudl be easily used in a pedal.
________
Magic Flight Launch Box Asthma


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## Catch22 (Feb 21, 2010)

Ok, in reading about controllers, that makes sense. The motor rating is only what it draws when working properly. If you load it, the amps go up significantly.

So looks like the 4QD is probably my best option unless I find an actual unit from a hoveround.

I know I will have more questions once I get to the point of actually installing the motors and getting them working.

Thanks again.


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