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AC Electric Motor -HELP-

BlueJello

Dec 15, 2016
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I'm making a motorized radio flyer wagon. I build things like this a lot, but I almost always use gasoline engines. Since this project isn't meant to go nearly as fast as my others, I thought I could use electric motors to save on gasoline. I have an AC Electric Motor from a band saw, but I know enough that an AC motor won't work on DC current, because of the coil setup. How would I convert DC to the required power for this specific motor? How does changing the voltage or amperage of the power source affect the speed and power of the motor?
Motor Label.jpg

EDIT: I didn't mention that I'm using a 12 volt battery, from one of those kid's car things.
 
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Bluejets

Oct 5, 2014
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Motors such as this draw a lot of current (4 to 6 times full load) when starting.
Let alone that the full load current is 8A,...(??? difficult to see) a dc to ac converter would be expensive to cover the loading.

Also difficult to make out the hp rating...it looks like it should be 1/2 hp given the current above.
No idea what 1/2B means....maybe a typo error.

I have no idea what a radio flyer wagon is but, with regards to the motor choice between dc and ac, it would be a good idea for you to Google up the differences.
One notable would be that the ac motor would normally not have anywhere near the torque of the dc counterpart.
The differences between ac and dc motors are more involved than just "coil setup".

I'd stick with the gas engines personally.
(besides, extension lead alternative woul be a no brainer):D:D:D
 

BlueJello

Dec 15, 2016
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a.) It is 8, the label was torn slightly.
b.) It is 1/2 Brake Horse Power, meaning it was measured using a dynamometer to put resistance or "brake" the
engine, to test torque and horsepower.​
c.) A radio flyer wagon is a little red wagon.
radio-flyer.jpg
d.) If I were to use a gas engine, I wouldn't be able to do the design I'm planning, and it would cost me significantly more in parts and supplies. Is there any way to supply it with less power than it calls for, at the cost of lower motor power?
 

Minder

Apr 24, 2015
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You would be way farther ahead to find a low voltage DC motor such as used in a winch or other 12v/24v applications.
M.
 

BlueJello

Dec 15, 2016
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You would be way farther ahead to find a low voltage DC motor such as used in a winch or other 12v/24v applications.
Could you suggest some specs, so I could find or search a motor of that type? I don't know much about electric motors.
 

Bluejets

Oct 5, 2014
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Look at the brushless motors used in model aircraft perhaps.
These would require the use of a matched speed controller but they are many and wide spread and some are really relatively in-expensive.
They do also require an r/c signal to drive the controller but one can get these on Ebay for a couple of dollars......
...............................or maybe dc motors from automotive applications ( brush type)
As M said perhaps a winch motor but many I have seen are relatively low torque, the torque coming from the large gear down ratio.
One used to be able to source the auto generator for use as a low torque motor but sadly these are all replace now with alternators so no go there.
Perhaps windscreen wiper motors, window winder motors......???

Edit...thought about old battery drills...??
 
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BlueJello

Dec 15, 2016
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Look at the brushless motors used in model aircraft perhaps...
What does "brushless" mean when referring to motors?
Couldn't the speed controller be hardwired to work without an r/c signal?

Also, what does 3 Phase mean and why do brushless motors have 3 wires rather than 2?
 
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Bluejets

Oct 5, 2014
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Brushless motors are the newer type of dc motor. In fact they are AC but the controller does the work of converting the DC from the battery into 3 phase AC.They do not use brushes, hence ............
As opposed to the regular DC brush type motor which uses brushes to transfer DC current to the armature via a commutator as it spins.

The cost of buying a controller for the brushless motor which is controlled by an r/c signal is low nowadays and they were designed to that particular application. There are some controllers which use a variable pot but usually these are a combination of motor, speed control, controller arrangement.

At any rate the generation of an r/c signal is, as I said before, relatively easy with the purchase of a servo tester for a couple of dollars off Ebay. Just be forewarned that these operate on an arming sequence. That is, the throttle or servo tester unit has to be taken to full throttle or max servo travel first to "arm" the controller. Then return to low setting, after which the motor will be allowed to run.

3 Phases means the AC delivered to the motor coils is done in 3 AC sine waves, each 120 electrical degrees apart. This gives a natural rotation effect without the use of any starting windings as in single phase AC induction motors.

There are many places in Google where you can get a better understanding of the operation of all the different types of electric motor.
 
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BlueJello

Dec 15, 2016
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Okay, thanks for all the information. I'll post an update once I find something that works.
 

Minder

Apr 24, 2015
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Really the first thing you should do is find out roughly what torque you need, this can be achieved from anything such as a spring scale or a small torque wrench, any reduction you may use will multiply the motor torque by the rate of reduction.
If you have an auto wrecker nearby there are a few motors you may be able to use such as window motors etc.
M.
 
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