The motor I use is 200rpm. The following figure is the code I use
After a period of use, the motor port will burn out and start flashing。
I have replaced six motors… The motor in this position is always broken…
What type of load are you putting on this motor?
Are you frequently reversing direction? If the motor is 100% spinning in one direction, are you slamming it in reverse or does it come to a stop before you change direction?
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This motor is used to grab mobile goals.Should I stop the motor before changing direction？
In the manual operation stage, once the mobile goal is grasped, the motor will stop rotating.
If this is the case, I would highly recommend implementing a slew rate (at minimum; ideally you’ll also have P or PI loop to complement it) to allow the motors to ramp up at a reasonable acceleration. Right now I imagine the intrinsic jerkiness of your motor control is the source of the problem, assuming it isn’t a mechanical issue
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Sounds like a V5 port issue as compared to a motor issue
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But I have replaced six motors… 
Check your mechanical structure - imagine holding a 50lbs bag of sand and spinning right and then immediately spinning left, your arm and joints may have a somewhat painful reaction……now think of your motor and momentum, action, reaction, change of force etc if you keep loosing motors you surely are well outside normal expected operational parameters….so software can help but mechanical parameters need to be first within what the motor is expected to be capable of handling…torque range etc
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What does your clamp look like? Is there a gear ratio involved in operating the clamp?
I am falling back to experience here but I have had students use a motor to directly drive a clamp without any mechanical advantage. The 200 RPM motor was turning 90% to lock on to a bar. Motors don’t have enough torque to hold onto a mobile goal so teams need to add gears to give the clamp more torque. Usually a 12 tooth to a 60 tooth gear (1:5) ratio is enough.
Not having the mechanical advantage is like picking up a weight with your pinky finger. A motor would surely overheat and possibly fail.
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If this is just used to grab mobile goals, you prob don’t need to run it at 100% speed; Maybe tone it back to ~80 percent and see if that helps, Personally my team has a limit on how fast we run motors to prevent heat and possible burnout. Using a slew rate as suggested above is also a good idea.
is the motor set to 200 rpm in the program? also it might help to turn it slower if you can, or use a speed or torque cartridge in the motor depending on what it is used for.
Thank you for your suggestions.
I adjusted the speed to 70%, but I burned a port today.
But I found that the problem may be brain, because the motor port can be used normally, but the brain port is burned
You may have a problem with ESD, happens a lot with v5. I’d recommend looking up some topics on the forums titled around brain port burnout/broken. There are also certain, let’s call it accessories to help prevent ESD, V5 ESD Protection Board Revision 3 (Save your V5 Ports!) but it is at the time of writing unknown if this will be legal to have during competitions. (Currently QnA Question 903)
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This is the key piece of information here. Usually a flashing port light means that the motor is receiving power from the brain, but is unable to communicate with the brain because the rs485 transceiver is burnt either in the motor or in the brain. From your description it sounds like static is repeatedly killing the rs485 transceiver in your motors. To try to reduce the likelihood of this happening you’ll want to make sure you’re using the new anti-static field tiles. Additionally, during practice you can use the ESD protection boards that @incognito mentioned. It’s worth noting though that they are illegal to use during competition, and that there is an open Q&A asking if it is legal to leave them on the robot unplugged for competition.
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Thank you for your advice. In the past week, after I adjusted the speed of the motor to 70%, a port in my brain still burned. But this time I know that the problem should be the static electricity on the floor mat. Do you have any good ways to remove static electricity? Now the weather is getting cold and static electricity is beginning to increase
We use a chemical called Staticide on our fields. I would think an array of anti static fabric sprays would work.
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Thank you for your advice. It’s very useful to me
In the past week, our motor and brain ports have not been damaged. At present, we believe that the main reason is that the robot pushes the ring on the site while driving, and the static electricity is generated by the friction between the ring and the floor mat. Therefore, we spray some anti-static liquid during each training, and spray some water at the same time to make the air moist. This can greatly remove static electricity.
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Since wire string is now permissible, it should be possible to “ground” your robot from static build up by dragging a wire.
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