I have a position, torque, and velocity question.

[scrambled]

I am trying to reconfigure my VSD-e servo drives and I have a question. According to GDtool, there are three choices for the type of drive. Torque , position, and velocity. I am using Mach to control my cutter. Can someone explain the differences to me and when should each be used?

If I am using position mode, do I need to tune the drives for torque and velocity?



Steve

[Montabelli]

with mach 3 you have to use position control, step & direction. the loop is closed in the VSD-e. I highly recommend you get a smooth stepper, as Windows is prone to interrupts that seem to occasionally give machines the hiccups.

You should however tune your motors in all three modes to get the best response.

[Xerxes]

Steve,

Use position mode with mach. However, you must have Torque mode tuned properly before going to position tuning.

[scrambled]

Tero-

I am having problems with my tuning. I can tune for torque with no problems, but when I get to position, it appears that the GDtool is locking up.

Everything was working last year, then I changed the gearboxes out. I went from 5 to 1 to new gearboxes that are 30 to 1.

I have had to change the setting in the trajectory planner to to alomost a minumn setting just to get the GDtool running.

There are times when I press the step response, and nothing happens. The little hourglass icon appears, and the capture screen for the response tab never show up. Then the drive gets an overcurrent fault.

I have to clear the fault, reset the drive, then make changes and hope it works on the next try.

I tried last night for an hour to hunt and peck for a set of settings that would work, and I never found a correct setting. This is on the X axis. I was able to tune the other A axis for the gantry. These are the same motors (keling 1125 oz in motors) on Thompson Duratrue 30 to 1 gearboxes.


any idea what is happening to the response tab settings?



Steve

[Xerxes]

Steve,

That's actually a bug of GDtool (fixed in upcoming version). The bug is that if fault occurs during step test, no graphs from that test are displayed. So if you get overcurrent fault, you just need to fix your torque tuning & current limits so that no overcurrent fault occurs.