Problem burning ibt2

Currently I am building a 3dof. The motors are 24v, 350w geared. With arduino R3 and ibt2. All the connections are per the diagram. When I use ecm3 (I did change to mode 2 for the program to arduino)I follow the instructions step by step with the first motor, and it works fine. I get the first motor to run fine and it runs smooth. When I try to go and set up the second motor, is when the problems begin. It’s runs for about 10-20seconds and it burns not only the ibt2 for the second motor but, also for the first one. I have double checked the connections countless times, I tried different psu, I tried one psu for both motors, separate psu for each motor, all with the same results. The psu are 24v 50amps. I even tried lowering the psu to 20v. I tried the Fpwm a 25 kilohertz and 20 kilohertz. Tried switching motors No difference. When I run it, it has cooling fans, even though I don’t think heating is the problem because when they burn they don’t feel hot. Why do my ibt2 keep burning?

IBT2s are known to burn out at 24V, working configurations that I know of are:
1. 250W motor with a supply of around 18V.
2. two ibt2's wired in parallel.
3. removal of the heatsink and application of thermal paste to the IBT2 + extreme version, sanding down the paint from the areas under the heatsink to better dissipate the heat + thermal paste.
I have burned about 6 ibt2s myself.
I tried 1 and 3 but finally I bought this controller
https://www.xsimulator.net/community/threads/reasonably-priced-100a-motor-controllers.17638/
So far it works fine with 24V 13.4 A 250W motors.
I do not know how it will behave with more powerful motors, theoretically it supports up to 100A but it is however made in china
Mount the KBPC5010 diode on the power supply to protect the power supply from regenerative current.
Do you have one 50A power supply for three motors ?

Thanks for you help , I already tried number 3 , I tried from 17 volts (that’s the lower my psu goes) all the way to 24 volts I do have a psu per motor. I’m not and expert on this but I think if power was and issue when I run a single motor I will see problems already but like I said before the problem is when I connect the second motor to test that burs the ibt2s ,burn then so fast that I’m not even get a chance to Test the second motor.
I was thinking to run each motor with they on arduino ,since I have not problem running just one motor,but how you setup 2 arduinos or 3 with scm3 utility when you can only choose 1 port?

Ok, will try to help.
1. first a description of how it should work: in SMC3Utils there should be two motors working properly without load, other behaviour indicates some kind of bug, hard to find remotely.
2. question how do you test? in my experience turning on square wave or fast movements of manual mode burn IBT2.
3. do the test by switching ‘Sine’ on the lowest possible voltage if again IBT2 fails , again check the wiring.
4.Show your settings in SMC3Utils and exactly what motors you have .

Thanks again for your help.
When I test the the first motor it runs in sine ,in manual in square with load and no load no problems.when I give power to the second motor like I said before I’m not even get a chance to test it because it burns the IBT’s.
The pic of the utility is for motor 1

A hard case
I am running out of ideas.
Looking at the pictures:
- why isn't the green line in the middle and overlapping the purple and blue lines?
below the correct calibration , the other settings are only correct for me, do not suggest them




It's all a bit mysterious , did you swap the motors in place maybe one is faulty and overloading IBT2?
Did you run them directly from the power supply?
Looking at those motors they look the same as my 250W 75 RPM

The green line is not centered with the blue because when I took the pic the rig was in resting position (power off), I did swap motors thinking the same as you but that was not the problem
Yes it looks the same motor the different is my motor is 350watts

Question do you test the motors connected to the seat ?

Yes

Do you know if Can I run an arduino per motor ?

Detach from the seat during testing.
Yes you can easily set up one arduino for each motor for testing in SMC3Utils , each arduino will have a different COM port in Windows, just edit the SMC3Utils.ini file
in the SMC3Utils directory, or make two directories each with a different port entered.
I don't know how to configure it in simtools, where you can only enter one port, so it won't work.
Maybe in FlyPTmover it is possible to set 2DOF on different Arduino.
I use Flyptmover.

Thanks I will try

Problem solved! I bought the motor controllers that you recommended me and now everything works perfect! The ibt2 controllers was my problem they couldn’t handle my motors I guess. Thanks again for your help!

Hello guys,

I'm building a 2DOF with the exact same motors .

I've got 1 power supply (24V 50A) and one IBT2 for each motor.
An arduino uno with SMC3.

For me the set up is quite working, SMC3 configuration is OK and the motors are moving perfectly.
When i sit on the chair, still working for fwe seconds (when motor is on load, about 80% of MaxPWM at 120),
and then just lose the torque, PWM (yellow line on SMC) goes 100% but nothing move on motor.
I need to go over limits and switch back to ON to get motor moving again. --pic joint

I understand that you've changed the IBT2 controller, so I'm going to do the same, but I'm hesitating between a sabertooth 2x32 and the model you mentioned above (100A) which is much more affordable, can you confirm that it works perfectly?

Thanks

In the drawing you showed you can clearly see that the signal from the potentiometer (green line) went below the level set by the max limit so the arduino turned off the motor to avoid mechanical damage.
Post your thread and show exactly how you built your 2DOF especially the arm rotation measurement circuitry

Hi Attyla.pl,

The green line went below the limit because off current loss not the invers.

The probleme is mostly corrected by changing the Fpwm from 35KHz to 20KHz as mention in this post
"
Ibt2 with 24v?
Discussion in 'DIY Motion Simulator Building Q&A / FAQ' started by xFFBx Tearier, Dec 6, 2023.
"( i dont have link permission yet )

But it's still there if too much current is need on motor to hold the load.


I'm a bit shy about showing a simulator that hasn't yet been debugged, and I was thinking of sharing it once it's stabilized and reliable.

Arm rotation measurement as been done by hand and for the time being, I've moved the actuators away from the pivot point to give the motors more leeway and sacrificed movement amplitude while I debug the simtool and VR motion compensation parts.

I'm sorry but I completely don't understand what way of measuring rotation you are writing about, there is nothing to be ashamed of just show pictures not such things on the forum we have seen
From my experience I know that the important thing is care and accuracy, often problems arise from their absence.
Below is my way to measure the rotation.

Here is some pict,
I misunderstood your question, I thought you were asking how I calculated the mechanical dimensions...
the position feedback is done by a potentiometer, apparently the same as yours, and I applied a ratio of 2 between motor and potentiometer because the motor only works on 120°.

Just change the controller to 100A , IBT2 at 24V overheat very easily.
Did you balance the upper platform with the seat to ensure an even load on the motors ?

https://www.xsimulator.net/communit...-of-gravity-to-balance-a-motion-simulator.55/

Yes i did, and it's still well balance when i'm into it.

On the pict i've give the motors position is not optimise i need to rebuild the chassi.

i've commande the 100A module, while waiting for it, i'm gonna work on motion compensation, do you use some ?.

Thanks for your time.