Robot Move unexpectedly even in Manual, T1 mode

    Hi.


    We had this unexpected occurrence while changing the DO from off to on.


    Control Panel : Manual Mode
    Teach Pendant : On
    Robot Controller : T1

    Trigger : HomePos signal set from 0-1 (DO is turned on when reference position was updated)
    Occurrence : Robot move in normal speed to WaitPos (Robot program)


    Is it possible for the robot to move through production program (here, PNS0003) after conditions are met even the teach pendant is on T1 mode (not automatic, speed 250max) and User Control Panel in Manual mode?? ??? ??? ??? ???


    Robot suddenly move in normal speed after triggering the homepos do signal.


    What happened is...
    We are running a production program then the robot stops because homePos signal was not triggered because of insufficient reference position tolerance.
    Then we turned the control panel to "manual mode", set the controller to T1 mode, and turned on the teach pendant.
    After that we update the position for the reference position in the current position...


    Then, suddenly, robot moved and crash to nearby machine.


    I appreciate any help.
    Thank you.

    It should not be possible for the robot to move at full speed in T1 and cannot move without the deadman switch held. Either it wasn't really in T1 or there is something seriously wrong with that robot.


    Some robots have a T2 mode key switch that allows full speed. You might check for that.


    What model robot and controller?

    Thanks for your reply.


    The robot model is : R-2000iC 165F
    The controller is : R-30iB


    There is also a T2 mode but I didn't use it because I only wanted to update the reference position (to output the DO signal).


    I am also not running any program in the teach pendant.
    I was just simply updating the reference position, then the DO turned on and the robot suddenly moved.


    I am not quite sure about the cause and why the robot moved.


    Initially, robot is in production for final process testing, then the robot paused because it was waiting for some signal feedback (the DO from ref pos).


    So, we then turned the mode to T1 and the panel from auto to manual mode, switch the pendant to 'on' and started updating the reference position.


    Can the robot move remotely (from plc input) even the controller is in 'T1', teach pendant in 'on' state, and user panel in 'manual mode'?

    I've had controllers where the keyswitch of Auto/T1 was not functioning OK. When switching from Auto to T1, the info on the Teachpendant still displayed Auto. We had to fix this inside the cabinet, something was broken there (don't remember what anymore).

    WOW I had to read it like 3 times to get a picture of the problem.


    1) I will checked if t1/t2 is reliable (damage, dirt, lose wires, etc)


    2) Fanuc robots dont have a mind on their on. The robot crashed because it was told to go home and it took the short path


    3)What I dont understand is the procedure for the PR
    quote " We are running a production program then the robot stops because homePos signal was not triggered because of insufficient reference position tolerance.
    Then we turned the control panel to "manual mode", set the controller to T1 mode, and turned on the teach pendant.
    After that we update the position for the reference position in the current position..."


    Why dont you do this programatically ? with out human intervention
    Compare the tolerance against a nominal value, or the last value, or zero value , or ....... and then accordingly load the current position into the pr and keep going. Particularly, I dont like this approach but at least is automatic

    Retired but still helping

    Edited once, last by Fabian Munoz ().

    A remote start of the robot by an input is not allowed in T1 mode. Are you sure this didn't happen right after switching it back to auto? Or that you didn't push the FWD button?


    I have had robots in T1 many times with the deadman and shift pulled in and the PLC give the start signal. Every time it says "Failed to run task" and nothing happens, no unexpected movement.

    Fabian,


    Thanks for reply. Sorry for my poor description. :wallbash:


    The program was already running in production and we just had to modify some robot paths.
    One of the point added to the new program was required to be a homepos and a digital output should be sent to the plc once the robot arrived at that position (reference position setting on teach pendant).


    After testing manually for collision, etc., we run the whole system including the process with the "cycle start" in the operator panel.
    During operation, the robot paused (sorry that i wrote stopped before) at the new position because it was waiting for the signal that the robot was in required position already (the do from ref pos i mentioned above).
    To trigger and continue the process we turned the controller switch from 'auto' to 'T1' (at this time, we received an alarm because the cycle has not stop yet. We did it because if we do cycle stop, the controller will run another different program) then, we changed the operator panel switch from 'auto' to 'manual', and enabled the teach pendant.
    We then proceed to updating the reference position to properly output the do.
    The do was triggered then, and suddenly, the robot moved.


    I was looking at the teach pendant panel then (to monitor the do) and couldn't see that the robot was moving. I was surprised when I heard the collision because I was not expecting any movement of the robot.

    @dwitm


    Thanks for reply.
    During normal jogging and operation, when the robot is in T1 mode, the robot moves slowly as expected. Also, when we changed from auto to t1, or to other modes when the cycle is running, we get an error so we think that the signal is properly sent to plc.


    Also, I am concerned about joint move... it moves faster than linear move even we are in T1 mode.

    HawkME


    Yes, I am sure because I remember the alarm we received after switching to T1 mode.　
    From what I know, if the controller is in T1 mode, programs can only be activated from the teach pendant (Is there a possible way to bypass this safety?). But what i only did to the teach pendant was turned the do to high (update reference position so it will output a do when the robot is in a certain position).

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