Posted - 08/07/2009 : 09:07:31
| Common questions about brushless motors:
Brushless motors require a controller designed specifically for brushless motors. There is no way to connect power to the motor without the controller, like you would do with a standard brushed motor. Each brushless motor requires it's own controller.
The most common brushless motor controllers you'll find on the market are designed for R/C cars. They interpret a specific signal that the R/C receiver sends to the controller. This signal isn't real easy to replicate with off-the-shelf parts, unless using either an actual R/C car radio system (transmitter AND receiver), or using a "servo tester." Either of these systems will require a 4.8 to 6 volt battery.
By the time you set up an R/C brushless motor system with dual motors and controllers, and the equipment to create the signal, you will have spent close to $400.
Now, evaluate what you are trying to gain with this system:
1.) More speed? Adding additional voltage to a cheap brushed motor will add additional speed without spending $400 on the brushless setup.... but you will hit a limit in no time. The motors won't last at much above 18 volts, and even if they did, the gearboxes won't handle much above that. Adding a high power brushless system will convert your gearbox to a melted pile of goo before you are able to see what it's capable of.... and then it's back to the drawing board to find a better setup.... that likely won't even use those brushless motors.
2.) More efficiency? These are slow and clumsy vehicle, already capable of hauling more weight then the vehicle itself weighs. The power usage of the brushed motors isn't that high, and it's easy to add capacity with larger or more batteries with little to no speed penalty, for very little money. The gains in efficiency will be non-measurable.
The only other type of controller that I have seen that is semi commonly available, and semi easy to connect to this type of vehicle, are motors designed for electric bike/scooters, which have the needed controller built in. These are large units that are not easily adapted to a gearbox.
For examples of more replies to these questions, click here:
Put in the search term "brushless" (without the quotes.)
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