Brushless and ESC help

[David]

I’m using a BP brushless motor and BP ESC with a 3S Lipo battery, and I use a microprocessor to generate a PWM signal (1ms – 2ms rate) for the ESC(with a BEC). The PWM generates 100% duty for the ESC, but the motor sometimes spins, and sometimese doesn’t spin at all. The motor spins 7 out of 10 times. I have tried to switch the motor cables (3 wires) to connect to the different ESC outputs, I couldn’t get the problem resolved.
1. Does anyone have these kinds of experience, or any suggestions?
2. If you have successfully used a PWM from a microprocessor to control a brushless motor through an ESC, could you tell which brand motor and ESC are? I have another ESC (Volcano 30A), but this ESC can’t make BP motor spin at all.

Best,

[Chris Anderson]

Are you able to drive servos with PWM using the same method? If so, it's weird that it would work for servos but not an ESC.

[David]

Hi, Chris:

Yes, I can the same PWM to drive a servo and change the servo position and speed by outputing different PWM duty cycle. But if I don't output 100% duty cycle from PWM to ESC, the motor won't spin at all.
David

[HugePanic]

i had similar problems with a veryvery cheap ESC and my remote control receiver! it simply didn't work well.

i can try to connect my arduino to my ESC and try it. it works well with servos, but i didn't do any tests with my esc. (just becouse it "should" work..)

if i find time today, will give it a try... all hardware is sitting around and waiting to be plugged in....

[HugePanic]

Hi,

i just gave it a try and learnd something. Maybe it helps you.

I connected my esc with motor to my arduino. Servos worked well, but the ESC worked a litte bit weird... i run each time i gave the command. (I route the receiver signals "through" the arduino).

1. The esc calibrates it self to max and min settings. This is especially important while startup of the arduino

2. My ESC chose the min. level always relatively high (about 30%). When the motor was spinning, and i cut down the throttle completely it didn`t stop instantly. This was always when i moved the throttle far below the min. level. When i cut it down to exactly to min level, it worked pretty well.


So first of all:
Check when and why your ESC set's its min and max values.

I hope i could help...

[Giles Barton-Owen]

Yeah, I have this problem with jeti ESCs, except occasionally it just starts smoking and I have to replace it. It is the same IC every time. About the same start success rate as well.

[HugePanic]

Currently i have a jeti ESC too.. :)

have to try others...

[David]

what motor do you use with Jeti ESC? Thx

[Giles Barton-Owen]

I use a PPO-2827 1000Kv from Purple Power Outrunners.

[Wayne Dancer]

You may just want to try a cheap GWS controller. I usually order from here as a combo motor/ESC pack. Pretty good deal.

[David]

Wayne:

Did you use RC Receiver/Transmitter to control GWS motor/ESC, or microprocessor to control ESC/Motor?

Best,
David

[Wayne Dancer]

I used a Basic Stamp 2 for a easy reference for PWM to try it out. I would actually really recommend a Castle Creations controller for a bit more reliability though. At least with the GWS you are not out as much if you fry it...

[wayne garris]

the BS2 will not actually output a 1 to 2 ms pulse every 50 ms i suggest use use a servopal in between the stamp and your esc .