Voltage reduction 14.8v to 11v

acedog

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My friend and me are trying to build a drone and bought a 14.8v 4s 10A battery. The ecs I think can take the voltage without a problem but the brush less motors we got are listed to take between 8.5-11. Is there a solution for this other than just putting some resistors in series with the battery?
 
Solution
If the ECS can take the 14.8V, you will be fine. The motor will only see the voltage provided to it by the ecs, which should keep it within its voltage range.

On brushless motors, voltage is proportional to speed. This means that as long as you don't exceed the max speed on the motors, the ecs will not provide higher then 11v to the motor.

Also, there is no easy way to reduce voltage cheaply, with low cost, and low weight. Best thing for that is a DC-DC buck converter which may be prohibitively heave for your drone

oczdude8

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If the ECS can take the 14.8V, you will be fine. The motor will only see the voltage provided to it by the ecs, which should keep it within its voltage range.

On brushless motors, voltage is proportional to speed. This means that as long as you don't exceed the max speed on the motors, the ecs will not provide higher then 11v to the motor.

Also, there is no easy way to reduce voltage cheaply, with low cost, and low weight. Best thing for that is a DC-DC buck converter which may be prohibitively heave for your drone
 
Solution
Depending on the controller you can adjust the trim so that at full throttle it limits the maximum speed. This will limit the voltage going into the motors. But like I said this will depend on how expensive the controller is. Cheap controllers and ones that come with the unit often do not have these controls. By controller I am referring to the hand held radio and not the Electronic Speed Control.
 

acedog

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The motors are brushless, and we are using an ardiuno uno to control the ecs(all 4).
Will it work to connect a voltage meter to the output of the ecs and then use that voltage output to determin the max setting.
 


Yes this will work although you may have to have a motor hooked to it for the ECS to put out any voltage. Some ECS's need to have a signal (voltage) returned to it in order to work. This is a safety measure some manufactures build into the the ECS.
 

oczdude8

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yes that will work. did you try it out?
 

acedog

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