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FANUC Increase Payload schedule-listing items

  • Hello all,


    I need to define more than 10 motion payloads (different toolings) but I can't find a way to increase this limit.

    Do you know if this limit can be increased and if so, how can I do it?



    Thanks in advance!

    Regards.

  • I recommend taking your various payload sizes and creating 10 schedules that cover the entire range. Then just select the closest one. In most situations this is an adequate solution, especially considering that many people get payload wrong altogether and still function :uglyhammer2:.

  • I wrote a small program to write to payload 1 and then set it dynamically. This might work for your situation. I haven't had the chance to test it though.

    Check out the Fanuc position converter I wrote here!

  • Hello Nation,


    I just tested this and it changes the payload values correctly! :thumbup:

    Just one more question, is there a way to know/validate that the robot is actually using this new values? Is there a test that I can do to validate?


    Thanks in advance :)

    Regards.

  • That is what I am not sure of.


    One way to test would be to put in a really heavy payload when you actually have a light payload and see if the arm overshoots its programmed points a little bit.


    Another way would be to run a test path in auto, one time with a light payload set, and another with a heavy payload set and watch to see if the path cycle times change. Heavy payload should accelerate slower.

    Check out the Fanuc position converter I wrote here!

  • That is what I am not sure of.


    One way to test would be to put in a really heavy payload when you actually have a light payload and see if the arm overshoots its programmed points a little bit.


    And you could adjust the collision guard to be more sensitive, triggering a false collision.

  • You could also look at the disturbance torque status page (MENU > STATUS > AXIS > NEXT > F4 for "DISTURB".


    The values in the allow column should change with the active payload.


  • I have never tested this personally so take this with a grain of salt: there is apparently a way to "trick" the controller to use the payload values for other motion groups as group 1, thus increasing the number of payload schedules available to group 1 beyond the default 10.


    From what I understand, this process it long and tricky, and involved changing variables via a Controlled Start, rebooting, changing some other system variables, booting back into a Controlled Start, etc. I unfortunately have never used the process (and willingly admit I'm not 100% sure it even exists), but I would suggest reaching out to CRC to see if they can walk you through the process.


    On an aside; will changing a payload's values programmattically on-the-fly via the above quoted $PLST_GRP1[1].$PAYLOAD=(n) system variable set mess with the motion planning algorithm that FANUC has running in the background to calculate motor torque, current draw, encoder counts/speed rates/whatever type of PID algorithm they have going on? I always assumed that changing the variable as it's being used could cause corruption of the motion planner.

  • Hello all,


    I'll make the tests that you all recommended me for validating if the new payload values are being taken by the robot, I'll also evaluate the option from HawkME and analyze all possibilities.


    Thank you all!

    :):):):thumbup:

  • On an aside; will changing a payload's values programmattically on-the-fly via the above quoted $PLST_GRP1[1].$PAYLOAD=(n) system variable set mess with the motion planning algorithm that FANUC has running in the background to calculate motor torque, current draw, encoder counts/speed rates/whatever type of PID algorithm they have going on? I always assumed that changing the variable as it's being used could cause corruption of the motion planner.


    I was also not really sure about this, as when someone manually changes any value inside the payload schedule page, we get a "Path and Cycletime will change. Set it?" message, not sure it after hitting “Yes” a new calculation was made but dynamically modifying the variables could result on something like what you mention, but maybe not and this is just a warning for just entering the value and it would be the same as modifying the variables directly.


    Tests will say :P

    • Helpful

    Gents, I just came across this post while looking for something else.


    You can change the number of payload schedules by changing the following variable. You must be in a controlled start to make the change.


    In controlled start go to $PLST_SCHNUM and change it to the number you need. Do a cold start and let the robot boot up. Go back into a controlled start and verify that $PLST_SCHNUM and $PLST_SCHMAD are both set to that number. Go back into a cold start and check the number of available payload schedules. I don't know what the max number you can have is; I've been up to 64.

    Good luck!

  • I changed these variables over a year ago to 125 and the robot performed fine. The only limit is the memory it takes up in the controller.

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