Model Boat Mayhem

Technical, Techniques, Hints, and Tips => BRUSHLESS Motors and Speed Controllers => Topic started by: hover tim on November 30, 2008, 04:00:46 pm

Title: Speed controller problem
Post by: hover tim on November 30, 2008, 04:00:46 pm
9i have got sa problem wiht a speed controller for some reason when using a servo tester i an only put some much throttle on and the motor will stop and when i use my transmitter it has a mind of it own i do know that i need a  forward and reverse and i suspect that this is a forward only would that be part of the problem its an e pro 30 A 
Title: Re: Speed controller problem
Post by: andrewh on December 01, 2008, 12:48:27 pm
Hover Tim

Sorry - I havn't quite understood the problem. 
Your servo tester should produce exactly the same signal as your receiver does, so any problems should be the same (unless you have a computer Tx, in which case ANYTHING can be happening (literally) depending on what you have told the Tx it is)

What is the motor, what is the speed controller?  My forward-only brushless ESC  uses the Whole throttle stick for forward speed control, and so the whole turn of the servo tester dial.  Depending on the motor and load on it they will do all sorts of starting, stopping, stuttering and sometimes sitting singing or buzzing, especially if used unloaded.  (My ESC is a cheap non-adjustable one and I don't expect too much from it)

Tell us more, please - have you got an airscrew on it?

BobF - interesting, but difficult :} 
Could you just sketch how and where the schottky diode goes on a brushless motor with 3 terminals all being fed with synthetic AC whichever way the motor is turning?
I agree with you in relation to big DC motors, but have NEVER understood how ESCs survive when used as forward/reverse but die when used forward only?
andrew
Title: Re: Speed controller problem
Post by: andrewh on December 01, 2008, 12:59:28 pm
Hovertim

The notorious "Brushless Basics" juggernaut has just reached the "reversing device for brushless motors" chapter

This is designed as a simple plug-in device which uses a servo to electrically change any two of the motor wires, thus reversing the motor.

It just might offer a solution to the reversing bit of the BL control.

andrew
Title: Re: Speed controller problem
Post by: BobF on December 01, 2008, 08:38:21 pm
Hi Andrew,
My posting was in relation to brushed motors. After I realised this was a brushless topic, I tried to remove or alter the posting, but was unable. I did post an addition to excuse my self, but the whole posting has now dissapeared. I'm glad to say. (well it has on my screen any way).
In my defence, I had not slept for seven months and was feeling rather tired, honest, would I lie?  <:(
Title: Re: Speed controller problem
Post by: Martin (Admin) on December 01, 2008, 09:42:25 pm
Just sweeping up Bob!  :-))
Title: Re: Speed controller problem
Post by: BobF on December 01, 2008, 11:03:53 pm
Thank You Martin,
Good to know you're still looking after me.   :embarrassed: