Testing a Motor on Brain

If you go to device/ settings info, you can test a motor without having program. Im wondering if the motors are set to 100 velocity and 100 torque, or if they are the standard 50 for each

idk I always pluged into the ports that ran the drivetrain and ran defalut drive program this let me test at any speed needed I believe its ports 1 and 2 if memory serves but that may be for vrc

i think you have misunderstood my question.
On an IQ brain, you can test a motor in device info section. This requires no code or anything.
Im asking if when you run the motor on device info, is it on 50 percent torque and velocity.

On the V1 brain it’s the Velocity. Torque would be weird since in lots of cases you are testing a motor that you are holding in your hand. (or at least that’s my use case since I don’t want to replace a dead motor with another dead motor)

what do you means its the velocity?
im asking whether the velocity and torque are automatically set to 50 or 100

So now I’m lost. On the VEXIQ brain you go Programs then X for Settings. On the Settings page select Device Info, select the port you want.

It shows you the Speed (RPM) the angle and the turns. You set the RPM you want to test at.

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how about torque? can u set it to 100 or something? if not what is it by default?

That I don’t know. My primary use for that screen it to see if the motor spins at all before I dive into their code. I’ve found that most motor fails are

  1. Battery packs reporting low voltages
  2. Wires not “clicked” into the brain / and or motor
  3. Shafts not pushed all the way into the motor

The motor test allows me to verify the voltage and if the motor spins. If all of that is good then I’ll dig into the program.

Now that I understand what you are really asking, let’s ask @jpearman to join this conversation

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just to clarify, this has got nothing to do with dead motors and whatnot.
Lemme explain fully story.
So basically, my teammate ran our cat mech on device info and it worked fine. So im wondering whether that means our cat mech can work when its only on 50 percent torque, because if by default it is on 50, then that means that we can increase torque to 100 and change gear ratio when we properly program it

The device screen will initially command the motor to spin at 100 rpm, you can adjust the speed using the up/down buttons. The device screen does not tell the motor to limit current, so the torque the motor generates will depend on the load applied.

The default velocity for VEXcode is 50 rpm, again VEXcode does not tell the motor to limit current unless you make that decision in your code.

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How about torque? whats the default torque?

Do you mean the default current limit?
By default, there is no current limit unless ypu set one.

so u mean the motor just enuf torque to make the mech move?

my question basically is, how much torque is a motor set to by default? or does the torque increase until it carries out the mission u want it to?

Torque/current and velocity are not independent of each other. For a given load, the more current you apply, the faster the motor will spin. And conversely, the faster you want the motor to spin, the more current you’ll need.

So you can ask the motor to spin at a particular velocity or a particular current. And you can set a “cap” on current, e.g., “Spin at X RPM, unless that requires more than Y amps, in which case apply Y amps”. But you can’t set both the velocity and the current to whatever you want at the same time.

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THANK YOU. I THINK I UNDERSTAND

There sort of is, I believe about 1.2A based on my notes. Motor source code would imply otherwise, but that’s what measurements and analysis of the value we send for limiting implies. There’s also theoretically a separate limit if we detect overheating, but that’s never been used on IQ motors as far as I know.

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