Fenceless education cert cart safety zone

  • Hi all. I just received a new Cert Cart with the ER-4iA unit on it. It has a laser scanner underneath to interrupt and stop the robot if a student approaches it while in AUTO mode running a program. I have run into an issue whereas the demo programs from the factory run as they should and the robot stops if someone gets too close, but any new programs I create, fail to activate the safety zone. So any programs I create, continue to run at programmed speed, even if someone comes right up to the unit. This is a huge safety issue in a high school lab, and I need to figure it out ASAP. Any one have any ideas?

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  • Hi,


    Maybe you can check and compare your program and the Factory program, it is really possible that you don't insert any parameters or set up about safety sensor signal, so your robot cannot stop at it should be.

  • The safety should either be hardwired or utilize a safety protocol. I would start seeing where the scanner is wired in and either take pictures or write it down to share with us. Also check the DCS menu to see what is setup there.


    Either way it sounds like it is definitely not right.

  • I just received a new Cert Cart with the ER-4iA unit on it.

    What's a "Cert Cart"?

    So any programs I create, continue to run at programmed speed, even if someone comes right up to the unit.

    That definitely does not sound right. Can you post the original program that does slow down? I have a bad feeling that someone may have used program commands to reduce speed instead of DCS. And program commands are not safety-rated.


    Could you make a complete backup of the robot, Zip it, and post the Zip file?

  • .. ER-4iA unit on it

    That's an collaborative robot.

    I have no experience with that kind of robots, but what they promise on their website, says that he can stop after a collision with humans, so it's not absolutely necessary to stop when a person comes nearer.

    May be You should read the manual.😉

  • That's an collaborative robot.

    I have no experience with that kind of robots, but what they promise on their website, says that he can stop after a collision with humans, so it's not absolutely necessary to stop when a person comes nearer.

    May be You should read the manual.😉

    I guess you mean CR-4iA which is a collaborative robot. The ER-4iA is basically the LR Mate 200iD/4S with another name and is used in the FANUC education cells.

  • That's an collaborative robot.

    I have no experience with that kind of robots, but what they promise on their website, says that he can stop after a collision with humans, so it's not absolutely necessary to stop when a person comes nearer.

    May be You should read the manual.😉

    The ER-4iA is NOT a colab robot. It is basically a LR200 on a certification cart for schools.

  • Well I figured it out. So the certification cart laser barrier is set up so that when started, a KAREL program begins monitoring for programs being run in AUTO. If the program being run in AUTO is not listed in the KAREL program's register, no light current interrupt is initialized. So, when the students build projects and want them to run in AUTO with the full proximity safety active, I have to go in to the register for the KAREL program and add that program name so it will monitor it while running in AUTO. This seems like a really stupid way to do it in my opinion, but that it what the FANUC tech sent me. I will update on anything else I find out. Thanks gents.

  • KAREL program begins monitoring for programs being run in AUTO.

    ...that is NOT safe. Even if the KAREL program is triggering DCS to reduce speed, the problem you've already encountered demonstrates why this setup is not safety-qualified.


    The area scanners should be wired into DCS safety inputs on the R30 cabinet, with DCS configured to slow and/or stop the robot based on the OSSD contacts from the area scanners. Normally, the scanners would have a distant "warning" zone that slowed the robot down, and an inner zone that would safety-kill the robot just like an E-Stop. Slow Teach mode would bypass the scanners, but in any other mode the scanners would limit the robot.


    Does this robot have DCS? If not, most R30 controllers, IIRC, have a Low Speed input that can be used to at least slow the robot down. It's not safety-rated, but it would still be better than what you currently have.

  • If it doesn't have DCS you should absolutely wire the scanner to the Fence safety circuit, terminals labeled EAS. Needs to be wired in to one or the other.


    I am very supprised that a Fanuc tech would do that. Are you sure they worked for Fanuc or was it a 3rd party integrator?

  • There is normally a manual delivered with the education cells with a description of the basic function and some exercises. Do you have such a manual?


    If not, please let me know. I have one (at least in German).

  • So upon some more investigation, they have DCS Cart. Speed Check zero and a DCS Cart. Joint Check setup so that if any program tries to run in AUTO that is not listed in the KAREL program register the robot throws the DCS and it refuses to run. I am being told that FANUC no longer enables the middle YELLOW speed reduction on the cert cart, and it is simply GREEN for okay or RED for stop when someone intrudes into the light curtain. This came from our third party vendor, so I am going to call FANUC support now and see if they concur with what I am being told.

  • There is normally a manual delivered with the education cells with a description of the basic function and some exercises. Do you have such a manual?


    If not, please let me know. I have one (at least in German).

    No manual came with the certification cart. I would love to see what you have.

  • So upon some more investigation, they have DCS Cart. Speed Check zero and a DCS Cart. Joint Check setup so that if any program tries to run in AUTO that is not listed in the KAREL program register the robot throws the DCS and it refuses to run.

    That really doesn't sound right. KAREL programs are not safety rated. If the KAREL program were being used as an extra layer above and beyond the basic DCS safety, this might make sense.

    I am being told that FANUC no longer enables the middle YELLOW speed reduction on the cert cart, and it is simply GREEN for okay or RED for stop when someone intrudes into the light curtain.

    Well, using Yellow or not is a judgement call.


    What disturbs me is that, based on your description, the light curtain doesn't stop the robot unless the program being run is included in the KAREL list. That is exactly backwards -- the light curtains and DCS should be configured to stop the robot completely independent of what programs are running.

  • That really doesn't sound right. KAREL programs are not safety rated. If the KAREL program were being used as an extra layer above and beyond the basic DCS safety, this might make sense.

    Well, using Yellow or not is a judgement call.


    What disturbs me is that, based on your description, the light curtain doesn't stop the robot unless the program being run is included in the KAREL list. That is exactly backwards -- the light curtains and DCS should be configured to stop the robot completely independent of what programs are running.

    So in your opinion, should I be contacting someone at FANUC to ask about this? In my mind, you are correct.

  • There's no doubt about, the light curtain must stop the robot when something is in the range of the curtain. It must also stop the robot even if no program is running, to prevent starting a program in that state. This must be independent from running background processes.

    Everything is said, but not from everyone. ;)

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