Is it possible to enable and disable DCS zones (CPCs) within the robot program and do so with the program logic? I've never tried to do this before, and honestly never seen it done or controlled with anything other than PLC. Basic concept is to set up the DCS to turn off or on a CPC area at the instruction of the robot. I know that if I manipulate a CPC by changing anything, enable or disable, then I have to apply changes and cycle power. Thanks for any assistance or ideas.
CPC programming
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BubbaSr77 -
September 29, 2020 at 11:07 PM -
Thread is Unresolved
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It is possible, but doing so with program logic will void your safety rating. To do it properly you need to wire in a safe input or use an input over safety protocol to mute the cpc zone.
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What do you mean "void your safety rating"? is this an internal controller thing or more like ratings received following an inspection? I've never used an input over safety protocol, so is this other software or option or is it terminology for the way something is done using existing inputs and such? Thanks for all your assistance it is very much appreciated.
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It is more of a hazard assessment thing. If you use non-safety program logic to disable a safety function then that function is no longer safety rated and cannot be considered in the hazard assessment.
A safety protocol would be a paid option such as Safety over EthernetIP. Otherwise most controllers include a few DCS safe input terminals you can hardwire to.
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I recommend you first understand safety ratings. Here's a good article: https://en.wikipedia.org/wiki/Safety_integrity_level
DCS is for protecting people, not machines, although it can be used to protect machines. DCS can be disabled by a safety rated input, that can be hardwired or from a field bus, but the disabling input MUST be safety rated to maintain the safety rating of the system.
Robots can be dangerous, but the danger can be mitigated through proper risk assessments and the correct hardware implementation to mitigate those risk.
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That makes sense, thanks for the article and the assistance