[HELP] Buzzing Motors with SBrick

[Saberwing40k]

Well, I recently took the plunge, and purchased a few Sbricks for use in my creations. In order to test the setup, I connected some motors, and used a profile I threw together. The setup I used has 2 SBricks being controlled by my device at the same time, and my problem is that, with one of the SBricks, I have two M motors hooked up to it, and when I activate them, they run just fine, but when I let the joystick return to center, the motors buzz, almost as if the SBrick is not fully shutting them off. I'm not sure if it's a problem with the SBrick, or not, as it is one I tested before, and it had trouble with controlling my other motors. Is there a setting I am not aware of that would fix this? Has anyone else had this issue?

Update: I tested it, and it seems to be an issue with the brick, although, in a bizzaro twist, I don't have the problem with sliders, only when those channels are controlled by joysticks.

Edited March 9, 2017 by Saberwing40k

[offroadcreations]

1 hour ago, Saberwing40k said:

Update: I tested it, and it seems to be an issue with the brick, although, in a bizzaro twist, I don't have the problem with sliders, only when those channels are controlled by joysticks.

That happens with me, but I don't know what it is. It also buzzes, but louder, when I move the sliders a little bit.

[deehtha]

I have had a similar effect with really low batteries and the IR system and other non Lego electric motors.  I suspect a little bit of electricity is being sent to the motor, but not enough to overcome the internal friction.

[Philo]

This is a problem with the M-motor that has a very large noise suppressor capacitor, acting as a short circuit when the motor is started. Power Functions IR-receiver V2 (which uses the same driver chip as the S-Brick) has the same issue. One M-motor is OK, two paralleled M-motors doesn't work at all, or start with a delay. Unfortunately I have no good solution for this issue, except using another motor type (L-motor for example)

Edited March 9, 2017 by Philo

[Bob De Quatre]

Got the same problem with BuWizz... so as Philo explained, this is mostly a "problem" related to the M motor.

[Philo]

Buwizz uses also the same driver chip, but with two channels for one motor (there are 4 drivers chips in Buwizz, vs. only two in S-Brick or one in IR PFS V2). So it is less prone to the problem with paralleled M-motors. My own tests on one Buwizz show that 2 motors were OK on 3 of the 4 ports, and had issues on the 4th one but only in high speed mode. But the problem shows up again with 3 motors...

[thatrabidhobo]

Knowledgeable responses like these is why I enjoy reading this forum so much more than other lego forums. Just felt right to say it in this post. 

[Saberwing40k]

Somewhat oddly, I have this buzzing problem with other motors, not just M motors. Just about the only motor I don't have this issue with is the servo motor. So, maybe we have a problem with the joysticks not actually shutting off power. I dunno, I will be in touch with their support, and will update if anything comes of that.

[dr_spock]

Could it be PWM making the noise?  Maybe the joystick center wasn't programmed to cut off power but send PWM to hold motor at a certain rotation point for servo motors and not DC motors?

 

[Saberwing40k]

I feel like if that were the case, it would happen with sliders too, but it does not. Anyway, even if it were PWM, the joystick center should still give zero, as that's the home position, right? Also, I thought the Servo PWM was sent out differently, over the control wires.