I set the speed limit of my servo motor to 1500 m/s, I set my acceleration and deceleration ramps to 5000, when I set my speed to 1000 and the acceleration and deceleration to 2000 and above, the servo goes into failure, when I set the jerk rate to 0.02, it goes into failure again, how do I set the inertia rates?
Inertia rates are usually only relevant when sizing the machine (so for the constructor), not when actually driving the machine. There it boils down to controllers - have you performed proper tuning of those? (Speed and position controller)
https://help.br-automation.com/#/en/4/motion%2Fmapp_motion%2Fanwendungsfalle%2Fanwendungsfall_autotune%2Feinleitung.html
Then you need to dive in deeper, Trace currents, lag error etc and see what seems to limit your system.
Since you were talking about inertia rates it sounds like you might have quite a big load on the axis?
I’d try reducing the acceleration and deceleration way down (really low, like 10% of the speed you are trying), try with that and then increase in steps (start with 10, go up to 100, 500, 1000) and see when it starts to fail.
IF your tuning is correct, maybe you are simply using a too high acceleration for the system you have and need to find the limit that way
There is no load on the axis, it just rotates something like a conveyor, I can go online and rotate it very fast in jog mode, but when I write a program and enter a distance and rotate the slide this far, it gives an error.
Can you detail the “an error” then, please? Which ErrorID?
Also, mind sharing the project (you can remove everything but the axis and the task you used to try driving the axis)?
maybe a scaling error ? I don’t know a physical axis that can move so fast 
No, I was doing it at these speeds
I totally agree with @christoph.hilchenbac here: These speeds sound veryhigh (1500m/s = 5400km/h or 3375 miles / hour). Considering the Autotuning parameters I’d guess the motor is not the biggest one either.
1500m/s also means that, e.g. using a motor with rated speed of 6000rpm would advance the mechanic by 1500m/s / (6000 rpm / 60) = 1500 m/s / 100 rps = 15m per motor revolution (which for a conveyor belt is a plausble value, for example, so not completely out of the possibilities).
Anyway, have you tried using much lower speeds? 1m/s for example? And then raising it slowly?
I once more ask for a dump of the project, since we can extract various details from there: The scalings in use on the motor, the scalings on the drive (I see you have applied some mechanical elements configuration on the drive), etc.
Also have you traced certain values like currents?
If you have not done any of that I would ask you to do so. Once you can perform movements at all and found the limits, we can then maybe figure out what limits a further increase up to your desired target speeds and accelerations
Uploading: ghymachine.zip…
I’m correcting it, it should be mm/s, I wrote it wrong
It looks like the project is still uploading 2h later - have you just zipped it?
Please do the following:
- Open the project in AS
- File->Save Project as Zip without upgrades
- Choose a filename
- Choose the option “Archive”
The last step is the important one, since it excludes the temporary and binary data, resulting in a much more lightweight export. (Binary data = your compiled files, which will be of no use to anyone else especially with different paths used; Temporary data: what the name says - temporary, we don’t need that)
A just zipped project which I see many do will exceed several 100MBs easily while such an Archive (even better: manual selection and then only export config and everything in logical) will usually be < 100 MB
Anyway, I will come back on monday to see if either the upload above worked until then or if you performed a new one following these instructions.
Best regards
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It is monday and the project is still not available to download, so I’d like to ask you to perform the lighter export detailed in the post above - in addition to trying the much lower speeds and accelerations and reporting back on that!
BR
ghymachine.zip (9.4 MB)
I did as you said, I created a trial project.
Before I dive in deeper (I have my ideas), I am still missing the answer to basically everything else I asked about twice: Did you try with lower speeds? 10? 100? Maybe even 100 still works? Do you know how fast you can go without the error? If not, can you please try? (Instead of a “no,” that doesn’t help.)
Also, your example doesn’t compile - i could fix it myself, but please note that in order to get people to help you it is best practise to help them help you without adding additional work onto them
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I tried it at lower speeds, when I bring the speed to 700-800 mm/s and increase the acceleration and deceleration to 1000, there is no problem, but when I increase the acceleration and deceleration above 1500, I get an error. When I increase the acceleration and deceleration, I get an error.
Speeds > 1500: Your limit velocity is set to 1500, so it’s pretty much clear why exceeding this gives you an error.
Acceleration/Deceleration: Please trace currents and position / speed + lag error.
This pretty much sounds like you maybe reach the physical limit of what the motor can output vs the machine coupled to it is opposing
My speed limit is 1500, yes I do not exceed this limit, so are you saying that I am physically limited to 200 mm in acceleration and deceleration?
I am saying we don’t know and until you are reacting to my continuous questions about tracing I don’t think we can progress any further here.