Motors not working?

VEX V5 General Discussion General Forum
#1

Hi, I’m just wondering why my team’s robot’s drive motors are working perfectly fine for a while but then one side with just give in. I’m not sure whats wrong, since we monitor the usage period (3 mins max.) and our robot isn’t very heavy, its around 14 pounds? The motors don’t even feel hot, though slightly warm

Also note that the motors are running on 393 high speed all on direct drive.

We appreciate the help and replies! =D

#2

try measuring the amp draw on each side with a volt meter. you might be triping a curcuit breaker

#3

There are several similar recent topics
https://vexforum.com/t/motor-tripping-circuit/20459/1
https://vexforum.com/t/strange-wheel-base-issues/20492/1

You don’t provide much information, see this thread for list of suggested information you should provide to get the best help;
[https://vexforum.com/t/solving-competition-failures/20479/1&highlight=information

In every case where motors are in use, then stop, then work again later,
it means you are overstressing some part of the circuit, and causing some protection circuit to stop the motors.

The usual generic answers to your common generic question are:

  • change your motor to port allocation
  • reduce friction in drive train
  • add programming to ramp your motors up and down
  • drive more gracefully (same as above, but by driver skill rather than programming)
  • stop trying to push the wall, or other robots
  • decrease your traction on wheels
  • increase the torque in your gear ratio to wheels](https://vexforum.com/t/solving-competition-failures/20479/1&highlight=information)
#4

https://vexforum.com/t/strange-wheel-base-issues/20492/1

You don’t provide much information, see this thread for list of suggested information you should provide to get the best help;
[https://vexforum.com/t/solving-competition-failures/20479/1&highlight=information

In every case where motors are in use, then stop, then work again later,
it means you are overstressing some part of the circuit, and causing some protection circuit to stop the motors.

The usual generic answers to your common generic question are:

  • change your motor to port allocation
  • reduce friction in drive train
  • add programming to ramp your motors up and down
  • drive more gracefully (same as above, but by driver skill rather than programming)
  • stop trying to push the wall, or other robots
  • decrease your traction on wheels
  • increase the torque in your gear ratio to wheels](https://vexforum.com/t/solving-competition-failures/20479/1&highlight=information)

Ah yes, please forgive me, as this is my very first thread.
The right side of the robot drive usually fails for a bit and comes back to life during practices and in real time matches. Thank you for the links! We greatly appreciate it.

#5

I also wondered if you were on the same team as The_VEX_Raptors as it was an almost identical question.

jgraber is right, without more information we can only offer generic answers. Tell us more about the drive, are the motors chained/geared together? Can you pin point which motor (or motors) are stopping? If the PTC in the cortex is activating then all the ports on that PTC (for example, ports 1 through 5) will stop, so do all five stop or just the drive? If one motor stops running it will often stall the other motor on the same side, especially if they are geared together. Do some experiments and get back to us with your results and perhaps pictures of your drive.

#6

The wheels to your right are dying and reviving, they’re in port 2 and 3.
The motor in port 2 (front wheel) is chained with high strength chain that’s geared 1:1 and the back wheel (port 3) is direct.

#7

  1. How many motors do you have?

  2. On which motor ports are they connected?

  3. What is the function of each motor?

-Eli

#8

We have 10 motors, but the drive is all 393, the left side is plugged into port 1 and 10, where the left side (the side that keeps dying and reviving) is plugged into port 2 and 3. The four motors are all set on high speed and are put as direct drive on the robot.

The only problem is with the left drive, which keeps dying and reviving, that’s it, every other motors works perfectly fine.

#9

Good information, you can eliminate one possible cause - the PTC in the cortex. If this PTC were tripping then ports 1-5 would all loose power (although I have to say I’ve never actually tested this but it’s what the spec says). As the motor in port 1 is still OK then this is not the problem.

You now need to try an eliminate

  1. intermittent wiring - check all your connections.
  2. A bad motor controller 29, you could try replacing one or both.
  3. A motor with a weak PTC (I don’t know if this is even possible) or a bad motor, try changing out motors or swapping with the right side and see if the problems moves.
  4. Some type of mechanical problem - friction, an axle that is to tight etc.
#10

Alright, thank you and thank you all for your help, I appreciate it greatly. I apologize if I may have caused any confusions to any of you.

#11

post 8 has too many left sides.
Try changing your code and motor ports so that
left side is ports 1,9 and
right side is ports 2,10

That puts two motors on each half of cortex

#12

Same here, our team has four motors for our wheels, it isn’t overheating, we have everything connected, and we have all of the ports programmed the way they should. Please help ASAP.

#13

This thread is almost 7 years old… make a new thread and list more details, like what type of motors you have, pictures, etc.

#14