How close to the fence with DCS

    I am working on a robot cell and want to make sure I'm in compliance with RIA 15.6. Parts are loaded into a lathe from behind the lathe with a robot on a pedestal. The robot comes about 15" - 20" from the fence when it's loading and unloading parts. There are DCS zones set up in the load scenario to prevent the robot from hitting the fence. The area where it can hit is an operator's area. The area is a sliding gate that is safety interlocked so the operator can not open the gate and get to the robot when it's working. The fence has 1" wire mesh. It's 96" or 102" tall if I remember right.


    Basically I need to know if DCS can be used to get closer than 20" to a fence when necessary. I thought there was some old rule about not being able to get closer to the fence than 20", but I thought that was before DCS.


    Will this pass RIA and OSHA standards? Do you need more info to answer my question?


    Sent from my Pixel 2 XL using Tapatalk

    You need to figure out the reach through of a persons finger through the 1" mesh, and the reach over of the fence. The ANSI/RIA documentation contains this information.


    see RIA TR R15.406-2014, [ISO 13857:2008, Table 2] for fence height


    see RIA TR R15.406-2014, ISO 13857:2008, 4.2.4.1, Table 4 for reach through for the mesh.


    Can you replace this section with lexan instead of mesh? Then use a dcs input from the safety interlock to disable the zone when open.

    I did a bit more research, According to the OSHA website the only requirement is to have a teach speed of 250 mm/sec when teaching, but it does reference that ANSI has additional recommendation.


    ANSI 1999 says to have 18" in all cases, this may have been updated in the 2012 addition.


    ISO says the 500mm is only required if high speed manual (T2) is available, I found this in CSA Z434 2014.

    Correct, my understanding is the 18" rule was changed to apply to T2 mode for a crushing distance.


    For normal operation your distance should be the stopping distance of the robot plus the mesh fence reach though distance.

    Edited once, last by HawkME ().

    Thanks everyone. I did some more studying and consulting today and came to the same conclusions you've all outlined here.


    1.) I have 1" mesh. Stop time is .1seconds. that means I should be able to get about 5.7" away from the fence in auto operation if I remember right. The robot will be 16" away, so I'm good there.


    2.) DCS is activated when the operator station door is slid open, so the robot can service the other machines. In my scenario the hazard (robot) is 1800mm away. With the height of the gates and guards I only needed to be 1500mm (going off memory) away from the fence.



    3.) Is there an up to date standard that mentions DCS? Why don't the current RIA standards mention DCS when it's used so extensively?



    Again, thanks for the replies. I never knew about this site before last night. What a good resource. Saved and marked in my Tapatalk app for future robot cell design questions.


    Sent from my Pixel 2 XL using Tapatalk

    DCS is the Fanuc name. Each robot mfg will have a a different name for their safety software. Under the latest RIA I believe they call it Safety rated soft axis limits or something to that effect.


    Sent from my SM-G930V using Tapatalk

    Quote from HawkME


    DCS is the Fanuc name. Each robot mfg will have a a different name for their safety software. Under the latest RIA I believe they call it Safety rated soft axis limits or something to that effect.


    Sent from my SM-G930V using Tapatalk

    What's the latest revision number? I don't see mention of the safety rated soft axis limits in 15.406.


    Sent from my Pixel 2 XL using Tapatalk

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