yuri1993
Posts: 16
Joined: Sun Oct 27, 2013 10:11 pm

Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 5:06 pm

This is really frustrating. Right now I have 2 motors connected to a l298N and both are being controlled through Pulse width modulation. My power supply is a 1 amp 13.5vdc/30vdc from Radioshack, when i try to turn on both motors with 13.5v none of them turn because there isn't enough voltage to power both (the other one just makes a beeping noise) So i change the voltage to 30v.

When I do this the motor controller breaks on me first time I thought it was a coincidence but the same thing happened with the 2nd controller. When i try powering one motor with 30v it worked fine but after trying two the controller no longer works no matter what i do. What is interesting is in both controllers that broke 2 outputs stay constantly on no matter what, so even without any gpio plugs connected once the controller is on and connected to the power supply it will output to one of the two motors.

the controller is rated for 36 volts so, what is it that I am doing wrong?


EDIT: tried plugging it in again at 30volts i got a popping sound and some smoke : /

Here is the schematic (pretty sure everything is wired correctly)


Image


EDIT: None of them were turning due to the face that they weren't getting enough amps, so I need a power supply and a controller that can easily handle 2 amps.
Last edited by yuri1993 on Thu Nov 14, 2013 6:09 pm, edited 2 times in total.

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joan
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 5:19 pm

Please post a photo of the connections you are making to the motor controller.

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Gert van Loo
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 5:36 pm

there isn't enough voltage to power both (the other one just makes a beeping noise) So i change the voltage to 30v.
Wrong! If you do not have enough power to run two motors you are unlikely to change that by turning up the voltage. You have to increase the current!
Which means turning you current limit to max. If it is already up to max your supply is not big enough.

But....
I don't think that is your problem because you say "when i try to turn on both motors with 13.5v only one turns".
The is NOT the typical symptom of not enough current. I would expect both your motors to stall or one or both running very slowly.
I think it is most likely that you have a wrong connection somewhere.

yuri1993
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Joined: Sun Oct 27, 2013 10:11 pm

Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 5:52 pm

Here it is as requested


Image
Last edited by yuri1993 on Thu Nov 14, 2013 6:08 pm, edited 1 time in total.

yuri1993
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Joined: Sun Oct 27, 2013 10:11 pm

Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:01 pm

Gert van Loo wrote:
there isn't enough voltage to power both (the other one just makes a beeping noise) So i change the voltage to 30v.
Wrong! If you do not have enough power to run two motors you are unlikely to change that by turning up the voltage. You have to increase the current!
Which means turning you current limit to max. If it is already up to max your supply is not big enough.

But....
I don't think that is your problem because you say "when i try to turn on both motors with 13.5v only one turns".
The is NOT the typical symptom of not enough current. I would expect both your motors to stall or one or both running very slowly.
I think it is most likely that you have a wrong connection somewhere.

You are actually corrrect neither would start if i tried to power them at the same time.

Thank you, it looks like it is an amp problem, so the next question is, what is a motor controller that can handle more than 2 amps at 13.5 volts?

and why would the motor controller break because i am trying to power to motors with more voltage?

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Burngate
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:04 pm

yuri1993 wrote:Here it is as requested


Image
Sorry, I don't seem to be allowed to view the image.

yuri1993
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Joined: Sun Oct 27, 2013 10:11 pm

Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:09 pm

Burngate wrote:
yuri1993 wrote:Here it is as requested


Image
Sorry, I don't seem to be allowed to view the image.

changed the link see if it works now.

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joan
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:17 pm

Some similar modules have a jumper which provides logic power from the motor power (for use if the motor power is 6V or less). If the motor power is more than 6V you probably need to remove that jumper.

yuri1993
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:23 pm

I do see some pins that say +5v next to the ENA and ENB pins but i do not have them connected, is that what you are referring to?

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joan
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:30 pm

yuri1993 wrote:I do see some pins that say +5v next to the ENA and ENB pins but i do not have them connected, is that what you are referring to?
No. Your module may not have such a jumper (a small piece of plastic with a wire connecting two pins).

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Burngate
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Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 6:44 pm

Can we see a picture of the other end of the wires - I'm assuming they go directly to the Pi, without a breadboard or similar?
Also a link to the controller board would be useful

yuri1993
Posts: 16
Joined: Sun Oct 27, 2013 10:11 pm

Re: Just broke 2nd motor controller, what is going wrong?

Thu Nov 14, 2013 7:14 pm

I'm pretty sure the solution to the problem is getting a 2amp power supply and a motor controller that can handle more than 2 amps.

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