deadman switch in external mode

  • Hello,


    KUKA KR 160 NANO

    KRC4 KSS 8.5.7

    ProfiNet MS V4.1.3


    I want to command my robot with an external teach pendant other than the SmartPad. This Teach is connected to a Siemens PLC that communicate with robot via PROFINET :


    KRC4 <------->Siemens PLC <--------> exeternal TeachPendant


    Our external teach pendant contains a dead man's button which is connected to the X11 interface. Since the robot is in external mode, the contacts (11-12 & 29-30, 13-14 & 31-32) for an external dead man are disabled. So we have connected this dead man button to the safe stop 2 (9-10 & 27-28)

    - First, is this contact suitable for connecting a Deadman switch?

    - The PLC must detect when this deadman is released. Is there any system variable related to these pins (similar to $SAFETY_SW for the smartPad enabling switches) ?

    In external mode, releasing the Dead Man sets $ STOPMESS to TRUE and if we re-press $ STOPMESS again becomes FALSE without any message displayed on the SmartPad. Also, the state of this button does not affect the state of $ USER_SAF.


    Thank you in advance for your help.

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  • MOM, thank you for your rely,

    We have developed several programs on KRC4 that will be called from an external Siemens PLC using Cell.src (We don’t have MxAutomation for the moment).

    The end user is not a roboticist, so we decided to connect the robot with an external Teach pendant. We have developed our custom HMI on this teach pendant that contains basically a button for each KRL program.

    This teach pendant is equipped with a 3 positions safety switch that we want to use to start or stop the robot (like the Deadman buttons in the Test mode). X11 has a contacts for two External Deadman’s buttons but it is only activated in Test mode.

  • So it looks like you are making a non-safety rated PLC deal with safety in EXT mode, which is by description not safe. In order to match the STOP categories of the enabling switch - for a release of the switch you can remove the $MOVE_ENABLE signal which will cause a STOP2, If the key is presses (panic mode) you can change DRIVES_OFF to have a STOP 1. Again this is not recommended.

  • this is still vague...


    if i understand correctly, objective is that KRC4 will (permanently) run in EXT mode, in which case external teach pendant is usable and it is supposed to allow "jogging" but - only when it's enabling switch is pressed?


    Also when servicing etc. you may need to ignore external teach pendant (and it's deadman) and use smartPad? And to ensure SPOC you want to prevent external Tech pandant use or make sure only one of the teach pendant is ever used at a time?


    My question (among others) is why not use ProfiSafe instead of X11? This will not only allow you to make safety logic but also get more safety signals from KRC4, including operating mode.

    1) read pinned topic: READ FIRST...

    2) if you have an issue with robot, post question in the correct forum section... do NOT contact me directly

    3) read 1 and 2

    • Helpful

    To my mind, the most important question is: will a human be within reach of the robot when this EXT-Mode deadman is being used?


    Because if the answer is yes, then your proposed setup completely violates RIA 15.06 and is inherently UNsafe, and is quite liable to get someone killed.

  • As mentioned before: the operation panel is for EXT only (no deadman switch needed - Emergency Stop only).

    While programming in T1 the safety gate is normally open and all programming should be done with the Smart HMI).

    During this time the operation panel has to be disabled for safety reason (SPOC)

  • dexterv , we don’t have a safety PLC . Dealing with the $MOVE_ENABLE will stop the robot, but as you said, it is not a safety signal. This is why we thought of connecting our Deadman button with the SIB via X11 (the safety board with a redundant contact and dynamic test etc...).


    panic mode , MOM, I Know that this is not a standard application, we want to keep the SmartPad only for the maintenance technician.

    We don’t use ProfiSafe because the robot is already equipped with SIB board. If we will use ProfiSafe, the Deadman button will be connected to SHS2 signal?

    The KUKA local support said that the safe Stop2 is not dedicated for connecting a Deadman button, and there is no system variable that shows its state.


    SkyeFire, one of our programs is a hand guiding application similar to this one:

    https://www.youtube.com/watch?…&ab_channel=VarunGopinath

    This why also I’m asking about adding a Deadman button because the manual guide handle must be equipped with another one.

  • you keep beating around the bush instead of answering the questions and confirming if assumptions are correct.

    hand-guiding "like that video" suggests that person is not just inside the cell but next to the robot.

    if this is not done carefully and with safety logic, you are violating key robotic safety principles.

    1) read pinned topic: READ FIRST...

    2) if you have an issue with robot, post question in the correct forum section... do NOT contact me directly

    3) read 1 and 2

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